CERTIFICATE
This is to certify that Mr. Arun Malanthara, has successfully completed the capstone project
“Study & Analysis of Tube Failure in Water Tube Boiler” under my supervision, in the partial
fulfillment of Final year, Twelfth Trimester - School of Mechanical Engineering of MIT World
Peace University, Pune for the academic year 2020-2021.
Prof. Atul M. Elgandelwar Prof. [NAME OFTH]
Capstone Project Guide Examiner
Prof. S. T. Chavan
Seal Head of School
Date : 1-July-2021
Place : Online

ACKNOWLEDGEMENT
It gives me great pleasure to present a capstone project on “Study & Analysis of Tube
Failure in Water Tube Boiler. In presenting this capstone project work number of hands
helped me directly and indirectly. Therefore it becomes my duty to express my gratitude
towards them.
I am very much obliged to subject guide Prof. Atul M. Elgandelwar, in School of
Mechanical Engineering, for helping and giving proper guidance. His timely suggestions made
it possible to complete this project for me. All efforts might have gone in vain without his
valuable guidance.
I will fail in my duty if I won't acknowledge a great sense of gratitude to the head of
School of Mechanical Engineering Prof.(Dr.) S.T. Chavan and the entire staff members in
School of Mechanical Engineering for their cooperation.
Arun Malanthara
B.Tech Mechanical
Engg. ERP No:
S1032171200
Div: B

ABSTRACT
One of the important parts of the thermal power plants are tubes carrying steam generally called
as boiler tubes. Any leakages in these tubes cannot be identified easily with human senses and
also boiler operating condition it is impossible to investigate these tubes or leak. In order to do
inspection, it requires shut down of the plant involving production losses. Though we do
inspection with human abilities there is possibility of occurrence of error. Frequent shut downs
for inspection leads to huge production loss. In recent days boiler explosions and its impact
have become regular news. The intent of this capstone project is to identify design related
failure of the boiler tubes under the thermal loading conditions. A single boiler tube is designed
and its behavior under thermal load operating conditions has been studied with the help of
Ansys R19 student release simulation software. This capstone project gives the detailed study of
the more vulnerable regions of boiler tube in design aspect. The tube failure may be a simple
problem unless it causes damage to the power plant and affects safety of the human being. The
problem due to tube failure is realized only when the cost due to failure estimated. The main
objective of our project is to reduce the number of tube failures occurring in boiler accessories
at thermal power station by analyzing the reason behind the tube failure and provide suitable
remedies for it. Tube failures in boiler accessories occur due to various reasons and major
reasons for failure among the various reasons are flue gas erosion, long term overheating and
steam erosion. The major failure reasons are taken from the tube failure. Major causes for
failure can be controlled by using following remedies such as optimization of flue gas velocity,
using tube material with better creep strength and by providing coating along the wall of the
tube. The optimization of flue gas velocity is done by computational fluid dynamics software
Ansys Workbench, the boiler tube material is chosen based on the cost, creep strength and
corrosion resistance, the coating for boiler tube is chosen based on operating conditions and
coating feasibility. The above remedies if implemented in the power plants can reduce the tube
failure to a major extent. The simulations were carried out using student release CFD software.
The analysis of the temperature distribution for every location inside the domain is conducted
by setting constant heat fluxes, and varying parameters such as mass flow rate of steam, steam
inlet temperature. The results showed that the temperature distribution at the tube wall
decreases with increase in mass flow rate of steam; decrease in steam inlet temperature.

INDEX
Abstract.......................................................................................................................................................
Content..........................................................................................................................................................
Nomenclature.............................................................................................................................................
List of Figures.............................................................................................................................................
List of Tables.............................................................................................................................................
1. Introduction..................................................................................................................................................01
Background 02
Boiler Mechanism 03
Boiler Tube 03
Boiler Tube Failure 04
Motivation of Project 05
2. Literature Review ...............................................................................................................06
Introductions 06
Purpose: Boiler Tube Failure Study 06
Purpose: Design & Analysis Reference Study 07
Purpose: Thermal Analysis Study 08
Purpose: Fluid Flow Analysis Study 09
Purpose: Structural Analysis Study 10
Gap Analysis 11
Project Background 12
Project Statement 12
Project Objective 12
Project Scope 12
Methodology Flowchart 13
3. CAD Modeling................................................................................................................................. 14
Design Validation forBoiler Tube 14
Dimension Reference for Boiler Tube 14
Material Selection for Boiler Tube 15
Defining Material Properties 16
Creating a Model 17
Meshing a Model 18

4. Mathematical Modeling..................................................................................................... 21
Thermal Analysis 53
Thermal Analysis at 170 ºC (443.15K) Inner Tube Temperature 54
Fluid Flow Pressure Analysis 57
At 75 Bar Pressure and 170ºC (443.15K) Inlet Temperature 58
Bend Design Customization 67
Extended at 75 bar Pressure and 110ºC Inlet Temperature 68
Comparison at 75 bar Pressure and 110ºC Inlet Temperature 70
Extended at 85 bar Pressure and 180 ºC (453.15K) Temperature 71
Compared at 85 Bar Pressure and 180 ºC (453.15K) Temperature 73
Extended at 110 Bar Pressure and 185 ºC (458.15K) Temperature 74
Compared at 110 Bar Pressure and 185 ºC (458.15K) Temperature 76
Pressure on Walls of Boiler Tube Due To Fluid Flow Pressure 77
Structural Analysis 78
Condition: 75 Bar Pressure & 170 ºC (443.15K) Temperature 81
Condition: 85 Bar Pressure &180 ºC (453.15K) Temperature 82
Condition: 110 Bar Pressure & 185 ºC (458.15K) Temperature 83
Extended Condition: 75 Bar Pressure &170 ºC Temperature 84
Unfixed Inner Plate 87
Unfixed Inner Plate Modified 88
5. Validation ............................................................................................................................89
From Transient Thermal to Transient Structural 90
From Steady State Thermal to Static Structural 91
6. Result and Discussion.........................................................................................................93
Safe Condition with No Loss of Quality 94
Safe Condition with Loss of Quality 95
Failure Condition 96
7. Conclusion............................................................................................... 97
8. Future Scope............................................................................................... 98
Project Significance 98
Project Scopes 98
Advantages Of Study & Analysis Of Tube 98
Advantages of Modified Design 98
Disadvantages of Study & Analysis Of Tube 99
Applications 99
9. References......................................................................................................................... 100

NOMENCLATURE
Notation Description
F friction factor
L length of pipe
ρ density of theliquid
µ Velocity of liquid
D Diameter of tube
K minor loss coefficient
Re Reynolds number
ρ Density of liquid
V velocity of liquid
D diameter of tube
µ Dynamic viscosity
e Absolute roughness
λ It is the thermal conductivity of the material
ΔT It is the temperature difference across the object Δx It
is the distance of heat transfer
Q Heat flux
A Heat transfer area of the surface
Hc Convective heat transfer coefficient
TS Temperature surface
Ta Temperature Air

List of Figures
Fig No. Title of Figures Page No.
1 Boiler Mechanism 9
2 Boiler tube 10
3 Design Reference for boiler tube 25
4 Creating Model 27
5 Meshing Model 28
6 Thermal Analysis 53
7 Fluid Flow Analysis 57
8 Bend design customization 77
9 Pressure Analysis on wall solid 88
10 Validation 89
11 Results and discussion 93

LIST OF TABLES
Table No. Title of Tables Page No.
1 Design References 25
2 Material selection for boiler tube 26
3 Creating Model 27
4 Calculation at 75 bar 31
9 Calculation of maximum allowable Pressure (IMG-1) 51
10 Thermal Analysis at 170 °C 64
11 Thermal Analysis at 180°C 65
12 Fluid Flow Pressure 67
13 Pressure on wall of Boiler tube due to
Fluid flow rate pressure 57
14 Calculation of Maximum allowable Pressure (IMG-2) 68
15 Pressure Analysis on wall solid 77
16 Validation 89

1
1. INTRODUCTION
BACKGROUND
Tube failures in boiler occur due to various reasons and major reasons for failure
among the various reasons is flue gas erosion, long term overheating and steam
erosion. The major failure reasons are taken from the tube failure. Major causes
for failure can be controlled by using following remedies such as optimization of
flue gas velocity, by clearing up the tube with condensation during boiler start-
up, by ensuring correct water circulation & distribution issues, by identifying and
minimizing the source of thermal or mechanical cyclic stresses, by ensuring that
there is no blockages exist within the tubes and bends, by using tube material
with better creep strength and by providing coating along the wall of the tube.
Boiler tubes are much important parts in case of thermal power plants because
they paves the passage for coal supply, steam generation and water carrying
purposes. These tubes are subjected to higher temperature conditions there will be
possibility of frequent failure of the tubes. Hence the boiler tube failure study is
of greater concern in recent era, nowadays boiler explosions in thermal power
plants are often recorded all over the world. These explosions are not only
affecting the electricity production of huge investments also dangerous to
operating personal in the power station. This The causes for boiler tube failure
are crack development and its sudden leakages of the tubes. This initial crack
development depends on several factors overheating, corrosion, creep, fatigue,
caustic attack, hydrogen attack, erosion by fly ash soot particle. Also boiler tubes
are loaded thermally i.e., Temperature loads hence thermal analysis of boiler
tubes are much failure predicting factor. Here Ansys simulation software is
employed to find out the design related failure of the boiler tubes. The thermal
analysis performed here is with simulation software hence there is variation in
results with practical values. Though there may be variation the required design
related failure of the tube is studied. The idea of employing simulation software
for real time problem has been become greater importance after FEA becomes
more popular. In case of real steam power plant there are several numbers of
boiler tubes carrying steam, water and combination of steam water here the tube
carrying water alone considered for the analysis because these tubes only
subjected to maximum temperature conditions, maximum pressure magnitude
conditions and maximum pressure conditions. In this analysis the temperature
assigned are average mean temperature of the boiler furnace for the outer tube
temperature and inlet water temperature for the inner tube temperature. Before
performing the thermal analysis, fluid flow analysis and structural analysis
several considerations have been made with the simulation. Boiler Tubes are
metal tubes located inside of boilers that heat water in order to produce steam.
There are two major types of tube boilers: water-tube boilers and fire-tube
boilers.

2
BOILER MECHANISM
A boiler is a closed vessel in which fluid generally water is heated. The fluid does
not necessarily boil. The heated or vaporized fluid exits the boiler for use in
various processes or heating applications, including water heating, central
heating, boiler-based power generation, cooking, and sanitation. The pressure
vessel of a boiler is usually made of steel or alloy steel, or historically of wrought
iron. Stainless steel, especially of the austenitic types, is not used in wetted parts
of boilers due to corrosion and stress corrosion cracking. However, ferric
stainless steel is often used in super heater sections that will not be exposed to
boiling water, and electrically-heated stainless steel shell boilers are allowed
under the European "Pressure Equipment Directive" for production of steam for
sterilizers and disinfectors. In live steam models, copper or brass is often used
because it is more easily fabricated in smaller size boilers. Historically, copper
was often used for fireboxes (particularly for steam locomotives), because of its
better formability and higher thermal conductivity; however, in more recent
times, the high price of copper often makes this an uneconomic choice and
cheaper substitutes (such as steel) are used instead. A Lamont boiler is a type of
forced circulation water-tube boiler in which the boiler water is circulated
through an external pump through long closely spaced tubes of small diameter.
The mechanical pump is employed in order to have an adequate and positive
circulation in steam and hot water boilers. Lamont Boiler is a high-pressure water
tube boiler. In 1918 Walter Douglas Lamont, a lieutenant commander and an
engineer in the US Navy introduced the forced circulation boiler. The Lamont
boiler is named after him. A centrifugal pump which forms the heart of this boiler
is responsible to circulate water within the boiler system. It receives water from
the drum and delivers this water to a distribution header as shown in the diagram
here. The number of headers may differ in numbers and depends on the size and
boiler design of each boiler. The boiler heating surfaces includes a number of
tubes arranged in a parallel form and the inlet ends are welded to the distributors
or the headers. A circulation pressure is to be provided during the installation of
the pump as per the boiler design and it should be sufficient to over come the
resistance offered by the tubes. An even circulation takes place with the helps of
the inlet nozzles provided at the inlet of tubes which creates the differential
pressure adequate to cover the variations occurring at fluctuating loads or uneven
firing conditions. The riser tubes outlet is welded to the collector headers and also
directly to the drum containing steam and water La Mont Boiler Working
Principle: The principle involved is, by employing a high velocity water higher
rate of heat transmission can be obtained. It deals with smaller quantity of water
and operates at higher pressures. Water is supplied through an economizer to a
steam separating drum which is set practically outside the boiler. A circulating
pump draws water from drum and delivers it to the evaporator. Water circulated is
about ten times the steam evaporated. Hence overheating of the tubes is avoided.
Water is rapidly evaporated in the tubes. The mixture of water and steam from
these tubes passes into the drum. Here vapor is separated and is flown into super
heater.

3
BOILER TUBES
The Boiler tube is placed in the path of flue gases. The main function of the
boiler tube is to heat the feed water. It consists of tubes with a feed water pump
attached to it. The feed water is taken up from the reservoir and circulatedthrough
the economizer where the feed water is heated before entering the storage and
evaporator drum. All power devices operate at high efficiencies required quality
steel tubes, to guarantee their safe and long term operation. These Tubes are
called as Boiler Tubes Boiler Tubes are specially manufactured to withstand high
pressure and temperature. Boiler tubes are used in energy type equipment’s like
steam pipeline, boilers, super heaters etc. Boiler Tubes manufacturer in India
Jindal Pipes, TATA Steels are the leading manufacturers of Boiler Tubes in
India. They use to perform rigorous inspection and testing procedures, state-of-
the-art manufacturing technology ensures theirs boiler tubes to withstand adverse
working condition. These companies have the capacity to produce the boiler
tubes in varied sizes, specifications and grade as per IS/BS/ASTM standards.
Boiler tubes should be approved by IBR (Indian Boiler Regulations) Boiler
tubing is used in these industries: Steam Boilers, Fossil Fuel Plants, Heat
Exchangers, Electric Power Plants, Cogeneration Facilities, Air Pre heater Unit,
Waste Heat Plants, Power Generation, Economizer, Super heaters.
Steam boilers use large amounts of energy raising feed water to the boiling
temperature, converting the water to steam and sometimes superheating that
steam above saturation temperature. Heat transfer efficiency is improved when
the highest temperatures near the combustion sources are used for boiling and
superheating with the cooled combustion gases exhausting from the boiler
through an boiler tube to raise the temperature of feed water entering the steam
drum. An indirect contact or direct contact condensing boiler tube will recover
the residual heat from the combustion products. A series of dampers, an efficient
control system, as well as a ventilator, allow all or part of the combustion
products to pass through the boiler tube, depending on the demand for make-up
water and/or process water. The temperature of the gases can be lowered from the
boiling temperature of the fluid to little more than the incoming feed water
temperature while preheating that feed water to the boiling temperature.
Identifying and correcting the root cause of tube failures is essential to help
lessen the chance of future problems. A comprehensive assessment is the most
effective method of determining the root cause of a failure.

4
BOILER TUBE FAILURE
Whatever the types of fuel being fired, all high-pressure boilers are bound to have a
tube failure during the course of their working life. There are six major groups into
which all tube failures can be classified. These six groups can be further divided in
to a total of twenty-two primary types. All high-pressure boilers commissioned and
put into operation go through a stabilization period, during which some teething
problems occur, including a few tube failures. Tube failure during stabilization
period. The tube failures in a boiler during initial phase of operation are different
from the types that occur after prolonged operation. During the initial period of
operation of boiler, the type of tube failures seen are short term overheating, weld
failures, material defects, chemical excursion failure, and sometimes fatigue failures.
The short-term overheating failure is mainly due to blockage in the fluid path by
some foreign material which gets into the tube surface during fabrication or during
erection of the unit. The blockage can also happen when debris after acid cleaning of
the boiler is not removed completely. This failure can be visually identified by it
characteristic appearance of a fish-mouth-like opening and so is also called as fish
mouth failure. Tube failure during normal operation period Any of these twenty-two
mechanisms can be the cause of a tube failure during normal operation. However, a
few like water side corrosion, caustic corrosion, hydrogen damage in the water wall,
soot blower erosion, damage during maintenance cleaning, and tube internal pitting
can be totally eliminated in a boiler if good operating and maintenance practices as
told by the boiler designers are followed. Hence it is not fully possible to avoid tube
failures in a high- pressure boiler, but the number of them can be minimized by
analyzing all failures and taking corrective and preventive action. Tube failure in
high pressure boilers follow a normal bath tub curve, with higher rate during initial
operation period, stabilizing to a lower rate during the normal operating period and
again increasing as the boilers agenda cross ten to fifteen years of operation. During
this period the boiler pressure parts are evaluated for their remaining life and
corrective action taken. A few photos of tube failure are shown below. A tube failure
is usually a symptom of other problems. To fully understand the cause of the failure,
you must investigate all aspects of boiler operation leading to the failure in addition
to evaluating the failure itself. A boiler that has a loss of feed water and is permitted
to boil dry can be extremely dangerous. If feed water is then sent into the empty
boiler, the small cascade of incoming water instantly boils on contact with the
superheated metal shell and leads to a violent explosion that cannot be controlled
even by safety steam valves. Draining of the boiler can also happen if a leak occurs
in the steam supply lines that is larger than the make-up water supply could replace.

5
MOTIVATION OF PROJECT
Boiler tubes are much important parts in case of thermal power plants because they
paves the passage for coal supply, steam generation and water carrying purposes.
These tubes are subjected to higher temperature conditions there will be possibility
of frequent failure of the tubes. A single tube failure in a 500 MW boiler requiring
four days of repair work can result in a loss of more than $1,000,000. Apart from the
generation loss, monitory loss and time loss the tube failure may results in the entire
boiler failure which may result in blast or explosion and that led to the loss of life
which is quite more precious and expensive than the generation loss, monitory loss
and time loss. On July 1, what should have been a routine maintenance check in Unit
5 of the Thermal Power Station- 2 of the NLC India Limited or NLCIL, formerly the
Neyveli Lignite Corporation in Neyveli, Tamil Nadu, turned deadly for the 23 men
who were still inside the Unit. The boiler in the unit blew while the men were
carrying out their work. The blast was so powerful that 13 workers died since then
and 10 reportedly are still in the hospital. It is only two months since a similar blast
in the nearby Unit 6 of the same station had claimed five lives and injured three
critically. This is the latest sordid incident in a spate of industrial accidents in India
since the Covid-19 lockdown. Since May 2020, there have been at least four
industrial accidents, two in Neyveli and two in Andhra Pradesh’s Visakhapatnam,
claiming at least 26 lives and injuring many more. India’s already poor record on
industrial safety has reached a new low following these recent incidents. As we were
going through our Forbes Marshall Internship, we came across different boiler
related concepts like manufacturing of boiler components, different steam traps,
piping system, condensate recovery etc. There we studied different failures
occurring in boilers most of them are in boiler tubes. In one of the Forbes Marshall
lectures, we studied about various cases of dangerous boiler accidents. Where we
came across different questions like what are the causes of the boiler accidents and
type. At the same time, we had to decide the topic for the final year project so we
made a group of four members. We found that Atul Elgandelwar has experience in
boilers circulation as well as good experience in the boiler industry. Under the
guidance of Atul sir we started our capstone project journey.

6
2. LITERATURE REVIEW
INTRODUCTION
PURPOSE: BOILER TUBE FAILURE STUDY
This Research paper mainly focuses on different types of tube failure due corrosion,
fatigue failure, overheating and erosion. This research paper also explains about selection
of material in boiler tubes. The Causes and mechanisms of failure area unit mentioned
and recommendation for hindrance of reoccurrence of such failure is provided. The tubes
had circumferential cracks and blown-up parts. All the failures were detected on the fire-
side surfaces of the tubes. Presence of Sulphur within the oil ash deposits on the fire- side
of the tubes seems to be the most reason for failure of boiler tubes. The cracking of the
tube at the well- intentioned was thanks to the combined result of S- induced corrosion
and attachment stresses. Circumferential fissures initiated by the liquefied ash were
increased greatly thanks to attachment stresses and resulted within the cracking of tube
Ate the part. it's counseled to avoid high Sculpture within the fuel and to take care of an
occasional metal temperature within the boiler. Super heater tubes of boiler of thermal
powerhouse were found busted. The rupturing and hole formation within the superheated
tubes is that the results of long run heating of the tubes. dilution of tube walls occurred
thanks to localized deposits and heating issues. For avoiding reoccurrence of such
failures, it's counseled to hold out regular scrutiny of scale deposition on the steam/water
facet surface and menstruation of degradation within the boiler tube thickness. During
fabrication and assembly of the pipes with the welded joints, care ought to be taken to
avoid generation of stresses at the weldparts.[1]
This paper highlights a methodology for failure investigation of super heater tubes made
of the material T-22 of a coal-based boiler. The process includes visual observation, the
identification of sampling locations, the determination of the bulk chemical composition
of the base alloy, micro structural investigation using optical microscopy, the exploration
of finer structural details using a scanning electron microscope (SEM), the evaluation of
hardness over samples obtained from different locations, the fractographic analysis of
different failed locations, the X-ray diffraction (XRD) study of corrosion products
adhered to inner surfaces, and the determination of the nature of the failure. Within a
span of four months, three successive failures superheated tubes were reported. The
tubes were observed to have undergone significant wall thinning. Microscopic
examinations using SEM on the failed region and a region some distance away on the as-
received tubes were conducted in order to determine the failure mechanism. Layer-wise
oxidation corrosion (exfoliation) in the inner surface was observed. Apart from major
cracking, a number of nearly straight line cracking were observed in the longitudinal
direction of both tubes. Close to cracking/bulging, void formation/de-cohesion of grain
boundary indicated creep deformation under service exploitation. Localized heating took
place. At elevated temperatures, the grain boundary also lost its angularity.[2]

7
PURPOSE: DESIGN & ANALYSIS REFERENCE STUDY
In this paper Ansys as well as Creo has been used for the purpose of performance
analysis of tubes using different materials. So, studying this paper was of great
significance for us. In this work we do analysis on economizer, problem that generally
occurred in the economizer is the deposition of scale in the tube which is generally
referred as fouling or scale. Scale decreases the heat transfer rate in the economizer
which reduces the efficiency of power plant. Corrosion is also another major problem in
the economizer tube as corrosion in the tube also decreases the heat transfer rate as the
economizer tube is subjected to high temperature. Under operating conditions internal
thermal impact and stresses are continuously affecting the life and performance of
economizer tube. In this work, analysis on clamping design used in economizer i.e. use
of half curved ‘C’ clamped economizer tubes to reduce stress concentration at clamping
surface of tube and done analysis economizer without taking the factor of scaling or
fouling and do the calculation. In another case, inside layer in the economizer which act as
fouling and again do the calculation and see the effect of fouling and see the reduction in
efficiency of boiler. The tubes are to be changed every failure time. Same is causing high
cost to organizations operating boiler and economizer operations. Modeling of
economizer in Creo software and then imported to Ansys for further stress and heat
transfer analysis. Design of economizer was made in Creo Parametric software with
dimension stated as above. After designing, import the design in the Ansys software and
define the various mechanical property like elastic modulus, density, poison ratio after
describing all mashing of design and after meshing, define the thermal boundary
condition. After defining boundary conditions, analysis was done and obtained the result.
After obtaining the result we change the geometry of economizer and put another inside
layer of another material inside the economizer tube which behave like scale or corrosion
in the tube and applying the same boundary condition and again obtain the result. After
obtaining the result we compare both the result and made conclusion.[5]
In this paper Computation of fluid flow and heat transfer in an economizer is simulated
by a porous medium approach, with plain tubes having a horizontal in-line arrangement
and cross flow arrangement in a coal-fired thermal power plant. The economizer is a
thermal mechanical device that captures waste heat from the thermal exhaust flue gasses
through heat transfer surfaces to preheat boiler feed water. In order to evaluate the fluid
flow and heat transfer on tubes, a numerical analysis on heat transfer performance is
carried out on an 110 t/h MCR (Maximum continuous rating) boiler unit. In this study,
thermal performance is investigated using the computational fluid dynamics (CFD)
simulation using ANSYS FLUENT. The fouling factor ɛ and the overall heat transfer
coefficient ψ are employed to evaluate the fluid flow and heat transfer. The model
demands significant computational details for geometric modeling, grid generation, and
numerical calculations to evaluate the thermal performance of an economizer. The
simulation results show that the overall heat transfer coefficient 37.76 W/ (m2K) and
economizer coil side pressure drop of 0.2 (kg/cm2) are found to be conformity within the
tolerable limits when compared with existing industrial economizer data.[6]

8
PURPOSE: THERMAL ANALYSIS STUDY
This paper presents creep analysis to estimate the remaining life of tubes used in water tube
boiler. Three-dimensional finite element (FE) models were developed with computer
software namely ANSYS Workbench 10.0 to analyze the tube temperature and stress
distribution. The FE results showed that the temperature and stress increase as the oxide
scale thickness increases. Formulating the creep behavior in terms of well-established
creep laws, the remaining life of the tube was estimated. In this paper, Finite Element
solution have been presented for obtaining the creep behaviour of axisymmetric boiler
tubes which are subjected to axisymmetric pressure and temperature loading. The
temperature variation was plotted with respect to different scale thickness and the results
show that as the scale growth progresses with time, the temperature keeps on increasing.
The same is the case with creep stress and strain. Finally, the residual life was estimated
using two approaches- using creep curve and life damage rule. Both the approaches gave
the same result. The life of the tube came out to be 26 years. This result correlates with
the actual power plant where service life varies from 25-35 years. Thus, the results are
fairly accurate. During the course of this investigation, two major areas were encountered
for which further work is needed. The first area relates to the creep behaviour and life
analysis of cracked boiler tubes. In our analysis we considered very simplified
assumptions that the surface of the tube was clean and no crack initiated or pitting formed
on the surface. If we consider actual boiler tubes, soot deposit, scale formation and cracks
are commonly encountered on the surface of tubes. Transversal and longitudinal through
crack or cracks to some depth are practically possible. Thus, the analysis of cracked
tubes should be the next area of investigation. The second major area of further study may
be the cases of surface pitted and corroded boiler tubes. While operation, boiler tubes are
exposed to abrasion and corrosion by the particles in the flue gas and steam and/or water
respectively. Therefore, somehow similar to the crack problems, the already developed
finite element method may be further developed to study the creep behaviour of such
eroded or corroded tubes.[3]
In this research paper we are going to discuss about Tube failures in boiler accessories
occur due to various reasons and major reasons for failure among the various reasons are
flue gas erosion, long term overheating and steam erosion. The major failure reasons are
taken from the tube failure. Major causes for failure can be controlled by using following
remedies such as optimization of flue gas velocity, using tube material with better creep
strength and by providing coating along the wall of the tube. Boiler tube failure continues
to be the leading cause for forced outages in fossil fired boiler. The tube failure may be a
simple problem unless it causes damage to the power plant and affects safety of the
human being. The problem due to tube failure is realized only when the cost due to
failure estimated. The main objective of our project is to reduce the number of tube
failures occurring in boiler accessories at thermal power station by analysing the reason
behind the tube failure and provide suitable remedies for it. Tube failures in boiler
accessories occur due to various reasons and major reasons for failure among the various
reasons are flue gas erosion, long term overheating and steam erosion. The major failure
reasons are taken from the tube failure.[4]

9
PURPOSE: FLUID FLOW ANALYSIS STUDY
A Cfd (Computational Fluid Dynamics) analysis is carried with two cases with and
without fins. Analysis of two cases is carried out to determine, how much value of heat
transfer has enhanced with fins. The model is solved using conventional CFD techniques
by STAR- CCM+ software. The Computational Fluid Dynamics (CFD) approach is
utilized for the creation of a three- dimensional model of the economizer coil. With
equilibrium assumption applied for description of the system chemistry. The flue gas
temperature, pressure and velocity field of fluid flow within an economizer tube using the
actual boundary conditions have been analysed using CFD tool. Such as the ability to
quickly analyses a variety of design options without modifying the object and the
availability of significantly more data to interpret the results. Hence from the analysis it is
found that heat transfer rate has been enhanced by providing the fins in case 2. As they
are considered as extended heat transfer surface areas there is significant increase in heat
transfer rate. Other technical explanation for the increase in heat transfer is, by creating
fins in the case 2, uniform flow of flue gas in the economizer is disturbed. Where as in
case 1 there is no obstruction in the motion of flue gas. Because of fins there is
disturbance in its flow, which creates turbulence into the motion of flue gas. This
turbulence energy is transferred to the fins in the water tube. Due to this more amount of
heat is transferred to the fins. Hence more amount of heat is transferred in the second case
than the first case. And this heat energy is transferred to water flowing in the tube. So in
this way we experience increased heat transfer because of the external fins which act as
increased heat transfer area and also due to generation of turbulence.[10]
In this study, the tubes of shell-tube heat exchangers have been arranged in two different
configurations, inline structure and staggered structure having 21 and 24 numbers of
tubes, respectively. +e shell has dimensions of 94.7 mm in diameter and 810.1 mm in
length. Likewise, the outer and inner diameters of the tubes are 12.5 mm and 11 mm,
respectively.Water has been considered as drive operating medium fluid for both shell
and tube sides. +e physical properties of water have been considered as those given in the
Fluent database. +e STHX has been modelled with staggered and inline tube structures to
analyse the heat transfer performance. From the CFD simulations for the shell-tube heat
exchanger, outlet temperatures of shell-tube fluids and their effectiveness have been
obtained. It has been observed that pressure drop is minimum for a mass flow rate of 0.1
kg/s, and outlet temperatures at the shell side and tube side are 40.94°C and 63.63°C,
respectively. +e increase in pressure drop for increasing mass flow rate has been
attributed to the turbulence, and thus higher shear stresses exist at the surfaces. It has
been observed that there is an excellent accord among CFD and analytical findings.
percentage difference between analytical solution and CFD simulation results show the
highest difference of 15.01% for heat transfer coefficient, 8.01% for shell side pressure
drop, and 8.39% for heat transfer rate.[11]

10
PURPOSE: STRUCTURAL ANALYSIS STUDY
In this paper the results of analysis presented in the form of total deflection and stresses
for incremented internal pressure was computed for various percentage of ovality.
During this process the bend undergoes plastic instability due to pressure and bending.
Pipe bendsimprove the pipe quality and trust worthiness in terms of pipe bend analysis.
Finally, the induced stress intensity and deformation of pipe due to internal pressure and
bending were noted. In this study, Stress analysis STAINLESS STEEL pipe was
developed and plotted to the various ovality in pipe bend by using support and without
support. The influence of ovality on variation of von mises stress, total deformation and
stress intensity of pipes are calculated by Ansys software and for experimental we are
using as pressure and we calculate the ovality of pipe. It is subjectedto many different
kinds of loading but for purpose three categories of codes of loads sustained load,
occasional load and expansion load. Compare to three of them with support on bend
section can withstand more pressure load. The application of internal pressure changes the
way of pipe bend behaves under internal pressure loading, not only in terms of its load-
deflection behaviour, but also in terms of distribution of stresses and strains. In this
study, Stress analysis of stainless-steel pipe without attached pipe was developed and
plotted to the various ovality in pipe bend. The results indicate that the pipe that meets
the specified minimum stress is not appreciably failure up to the 20% ovality.[12]
The analysis of tube sheet falls under ASME sec-VIII Div.-II, which recommends usage of
FEA to validate the design. Objectives are to create analysis SOP (Standard Operating
Procedure) in WORKBENCH, study the effect of tube sheet spacing on stress profile, To
optimize the structure with Spacing distance between two tube sheets, and Thickness of
the tube sheet. A tube sheet is sheet, a plate, or bulkhead which is perforated with a
pattern of holes designed to accept pipes or tubes. These sheets are used to support and
isolate to tubes in heat exchangers, filter and boilers support elements. Depending on the
application. The studies of existing system in pressure vessel one or two tube are used
with small size vessel. Here in this project is totally new design that is proposed there are
three tube sheets at equal intervals and combination of three pressure vessel in this
design arrangement of tube-sheets are equally spacing distance and vessel size will be
large as compare to existing. design of all model by using ASME Code Section-VIII,
Div.-II. Three space sequential tube sheet are final result is optimization of space, stress,
and weight and as per ASME Code design will be safe for that condition and cost will be
a reduces. For the validation of result obtained by the FEA software, experimentation is
to be carried out on the actual model. Using strain gauge and Ultrasonic Test Equipment
for experimental testing and then the results of this work are used for the validation of
results obtained from analysis software. Stress Result for Complete Vessel Analysis
considering all tubes masses, pressure on tube-sheets 0.01MPa and internal Pressure on
all other components as 0.32 MPa with 3 saddle supports stress is 123.18MPa which is
within the limit of allowable stress.[13]

11
GAP ANALYSIS
The gap analysis has been done and gap has been discovered with reference to the
study of various journals & based on the traditional sales and marketing technique of
boiler tube."Many plant engineers review information such as construction details,
painting, duct thickness, structural integrity, code documents and so on, but few
review the boiler’s thermal performance calculations, drum baffling system details or
thermal performance and circulation issues. However, engineers should review these
things before buying a new boiler plant, using either in- house expertise or third-party
consultants."Tube Failure Analysis and Residual Life Assessment in Water Tube
Boiler which was published by the author Dinkar Nandwana where he did the thermal
analysis of Temperature Distribution at Different Scale Thickness considering the
very small cut part of boiler tube. Traditional Sales and Marketing Technique which
is being followed since a long time i.e., the method used by the plant owners &
manufacturers which they follow before taking decision to make investment to
purchase the boiler tube for their plant. Marketing & purchasing of the Boiler Tube.
All Boiler Manufacturers provides their product catalogues to their customers into
which dimensions and material specifications of the boiler tube is mentioned and
most of these specifications are already known to the buyers, customers or plant
owners. But there is no provision to provide pre visualization of the conditions under
which boiler tube is going to operate. Review of thermal performance is required
thermal Analysis Should be Done in order to analyze and review the thermal
performance of the boiler tube considering different practical conditions in analytical
way. Prediction of flow phenomenon is not available for customers, buyers and plant
owners at the time of purchase. Fluid Flow Pressure Analysis Should be done in order
to analyze and review the fluid flow pressure variation and performance of the boiler
tube when fluid is flowing through it by subjecting the boiler tube at different
practical conditions in an analytical way. Insight of the working conditions when
subjected to various parameters is not available for customers, buyers and plant
owners at the time of purchase. Fluid Flow Pressure Analysis along with the thermal
conditions and along with the probe on the wall solid of the boiler tube should be
done in order to analyze, review and to obtain the Insight of the working conditions
by implementing the various parameters on boiler tube at different practical
conditions in an analytical way. Conditions at which loss of quality take place is not
available with the customers, buyers and plant owners at the time of purchase.
Structural Analysis on the wall solid of the boiler tube should be done in order to
analyze, review and to obtain the Insight of the working conditions by implementing
the various parameters on boiler tube at different practical conditions in an analytical
way. Traditional sales and marketing technique should be improved in order to
enhance manufacturers and customers purchasing satisfaction and to make purchasing
process more interactive. Can be improved by making analytical data, analysis
contours and simulations available to the customers, buyers and plant owners at the
time of purchase which creates trust between the manufacturers and customers
satisfaction and make purchasing process moreinteractive.

12
PROJECT BACKGROUND:
Our project basically deals with the study of tube Failures in Water Tube Boiler and
based on that study Analysis of Tube Failures in Water Tube Boilers with the help of
Ansys R19 student release simulation software. Study part consist of the detailed
study about the boiler tube and it's failure conditions, failure reasons, failure
solutions & theoretical & design failure optimization methods, supported by
analytical optimization methods.
PROBLEM STATEMENT:
To Study and Analyze the Tube Failure in Water Tube Boiler
Many times industrialists, manufacturers, buyers or plant owner who are willing to set
up a small factory want to pre visualize the conditions and situations before making
any investment.
Which type of tube they should select from the various manufacturers available in
the market.
What dimensions they should select from the available one.
How the tube which they are going to buy is going to work.
What safety SOPs they have to establish and formulate before commissioning and
establishing the boiler in their plant.
What kind of failure and damage they may have to deal with in future.
PROJECT OBJECTIVES:
The objectives of this project are to:
• To reduce the number of tube failure occurring in boiler at steam power plant,
thermal power plants or wherever water tube boilers are used.
• To enable the manufacturer to pre visualize the conditions and situationsbefore
making any investment.
• To enable the industrialist about different failure situations which they mighthave
todeal with in future.
• Allows the plant owners about the additional safety they have to follow.
PROJECT SCOPES:
The system is analyzed considering:
The capstone project will concentrate on the implementation of parameters that control
sand influences the performance of boiler with reference to the boiler tube.
This capstone project will allow us to monitor the parameters like temperature
impact & heat difference, pressure impact, pressure difference, fluid flow impact,
fluid flow difference between the furnace and the boiler tube. This capstone project
will allow us to monitor the various types of insight conditions which cannot be
easily seen and observe during the running condition of boiler by any human
observer the insight conditions which are not comfortable or suitable for the boiler
tube during its service.

13
CreatingaMeshStructural
Configuration
CreatingaMeshFluent
Configuration
Creating aMesh Suitable With
ThermalConfiguration
Selection of valid design/dimensions , Material and
inputdatabasedonexperimentalreadings
Reading from
Experimental Method
No
Mesh
Successful
Yes
No
No No
Check For Solver Pivot Error
→Solve → Simulate
Select Time Steps
→Select Required Solutions
Record Contours →Generate
Simulation
METHODOLOGY FLOW CHART
START
Creating a Model
Calculation of boundary
conditions
Select Required Solutions
→ Initialize →Record Contours
Implementation of Calculated
Boundary Conditions [Fluent]
Boundary Conditions [Thermal]
Check For Solver Pivot Error
→Solve → Simulate
Select Time Steps
→Select Required Solutions
Boundary Conditions [Structural]
END

14
3. CAD MODELING
DESIGN VALIDATION FOR BOILER TUBE
In order to design the CAD model of the boiler tube firstly we have referred
various designs, various parameters and multiple conditions under which the boiler
tubes are subjected. After the consideration of various designs and multiple
conditions we come to the conclusion that boiler tubes are subjected to maximum
impact by the effects and loads of high pressure and high temperature in high
pressure boilers. So, we have selected the design of La Mont boiler tubes.
SOURCE: International Research Journal of Engineering and Technology (IRJET)
We have referred multiple journals and research papers and amongst them the
prominent ones are “Performance Analysis of Economizer Using Different
Material of Tubes” & “Investigation of fluid flow and heat transfer of an
economizer” between them.
S. No Research Paper Author Publisher
1. Performance Analysis
of Economizer Using
DifferentMaterial of
Tubes
Ravi Jatola,
Gautam Yadav,
M. L. Jain,
B. More
International ResearchJournal of
Engineering and Technology
(IRJET)
2. Investigation of fluid
flowand heat transfer of
an economizer
C Rajesh Babu,
P Kumar, G
Rajamohan
IOP Conference SeriesECS with
IMCS18
DIMENTION REFERENCE FOR BOILER TUBE
We have referred multiple journals and research papers and compared the design
and dimensions selected in journals with the design and dimensions selected by
the boiler tube manufacturers which they have mentioned in their catalogue /
brochure and noticed there was almost no difference between them as wide range
of dimensions are offered by manufacturers. Therefore to select the more practical
approach we have selected the design and dimensions from the company’s
brochure. Because the design and dimensions and manufactured by the boiler tube
manufacturers are going to be in practical use at some point of time by the
industrialist or plant owners. So, we referred the boiler tube brochure of multiple
companies and noticed that all the companies offer same dimensions with same
specifications. Therefore we have selected the boiler tube dimensions from the
brochure of TATA Steels Boiler Tube. The selected boiler tube has the following
dimensions: OD = 114.30mm, ID =109.17mm, Thickness = 5.130mm

15
MATERIAL SELECTION FOR BOILER TUBE
Before proceeding towards the designing process material should be specified in
the Engineering data setup of ANSYS. The default material specified in ANSYS
Workbench is Structural Steel. Since, we are targeted to generate the condition
which is similar to the actual practical conditions. So, the material data should be
of the practical kind. Therefore reference has been taken from the Boiler Tube
brochure of multiple companies. Catalogues of Aditya Intertrade Pvt. Ltd, Pankaj
Trading Corporation and TATA Steels are referred along with the reference of
Journals & research papers, but in most of the research the material selected was
structural steel, which might create a gap between the hypothetical condition and
actual condition. So, the conditions might not be similar to the actual practical
conditions. Therefore material selected from the Boiler tube brochure was BS
3059: Part1: 1987 ERW-320 Low carbon. The elected material is common in all
the three companies’ brochure i.e., Aditya Intertrade Pvt. Ltd, Pankaj Trading
Corporation and TATA Steels. All these three companies uses a common material
which is BS 3059: Part1: 1987 ERW-320 Low Carbon Steel. The image from all
these three catalogue/brochure has been given in the following table figure.

16
DEFINING MATERIAL PROPERTIES
The properties of the selected material i.e., BS 3059: Part1: 1987 ERW-320 Low
Carbon Steel is not available directly in the AnsysR19 Student Material Library as
it was student version and not the commercial version. But in the standard material
library low carbon steel was available which can be directly taken although it is
not exactly the same. Therefore we selected the low carbon steel from the Ansys
Material Library and duplicated it by entering the properties manually which was
available in the companies brochure. The properties of the material which was
entered after duplicating the low carbon steel from the Ansys material library is
given in the following table.

17
CREATING A MODEL
The designing of boiler tube is done by taking in considerations the selected
material and selected dimensions. As per as the designed boiler tube the designing
of bend which is used to connect the boiler tube is also done with reference to the
thickness of the boiler tube, outer diameter of the boiler tube and hydrodynamic
diameter of the boiler tube. The number of tubes selected is five. All the five tubes
designed is connected by bends and supported by left & right edge supporting
plate on both the sides. Then as per as the distance between the tubes and bend
diameter left edge supporting plate and right edge supporting plate is designed in
rectangular form and weld option is used to connect the edge of the supporting
plate’s hole and surface of the tube. Designing of geometry is done in the design
modular geometry editor which is available in the ansys setup module. There were
two geometry editors available in ansys and the designing of geometry should be
done either in design modular geometry editor or in space claim geometry editor.
Here design modular is chosen for the purpose. There are multiple options
available inside the design modular geometry editor amongst them Sketch,
Extrude, Sweep, Fill, Fluid & Weld options has been used in designing of boiler
tube. The Length of tube is designed in XY-Plane, the bend of the tube is designed
in YZ-Plane and the left & right edge supporting plate has been designed in two
separate additional YZ Plane. The dimensions and design of boiler tube has been
shown in the following figure and table.

18
MESHING A MODEL
The designing of geometry is done by taking care of the constraints of student
version. If design is complex then our setup will be limited till the meshing part
only and we will not allowed by the software to proceed further ahead with the
process as student release is limited by 32000 nodes/element & 51200 cells/nodes.
So, in order to limit node elements and cells of the generated mesh we have used
different manual meshing for Thermal Analysis, Fluid Flow Analysis and
Structural Analysis.
For Structural Analysis we used Body Sizing Method on the entire geometry. Prior
to the mesh generation named sections has been created i.e., inlet, outlet, outer
surface, inner surface, solid domain, fluid domain, left edge support, right edge
support. The node and elements generated under this configuration are within the
limits of student release software. Therefore we can easily proceed further with
these configurations.
Mesh
Physics
Preference Mechanical
Smoothening Medium
Span Angle
Centre Coarse
Transition Fast
Transition
Ration 0.272
Element Size 124.79mm
Maximum
Layer 5
Growth
Rate(Inflation) 1.2
Growth
Rate(Sizing)
1.85
This is the view of mesh which was generated for the purpose of structural analysis.
The Nodes, Cells and Elements are under the control of limits specified by student version.
Modified Configurations
Method
Added
Body
Sizing
Element
Size
12mm
Behavior Hard
Nodes
Generated
153033
Elements
Generated
426008

19
Mesh
Physics Preference Mechanical
Smoothening Medium
Span Angle Centre Coarse
Transition Fast
Transition Ration 0.272
Maximum Layer 5
Growth Rate
(Inflation)
1.2
Growth Rate
(Sizing)
1.85
Modified Configurations
Method
Added
Patch
Conforming
Method
Method
Name
Tetrahedron
Element Size 12mm
Behavior Hard
Nodes 167048
Elements 416496
For Thermal Analysis we used Patch Conforming Method on the entire geometry.
Prior to the mesh generation named sections has been created i.e., inlet, outlet,
outer surface, inner surface, solid domain, fluid domain, left edge support, right
edge support. The node and elements generated under this configuration are within
the limits of student release software. Therefore we can easily proceed further with
these configurations.
This is the view of mesh which was generated for the purpose of thermal analysis.
The Nodes, Cells and Elements are under the control of limits specified by student
version.

20
For Fluid Flow Analysis we used Multizone method on fluid part and inflation
method on the solid part for the meshing of entire geometry. Prior to the mesh
generation named sections has been created i.e., inlet, outlet, outer surface, inner
surface, solid domain, fluid domain. Here left edge support, right edge supports are
not considered as Fluent flow solver preference does not consider additional
supported solid part. If we consider edge support, right edge support then it may
give error and wrong results. The node and elements generated under this
configuration are within the limits of student release software. Therefore we can
easily proceed further with these configurations.
Modified
Configurations: Solid
Method
Added
Inflation
Layer
Inflation
Option
Total
Thickness
Maximum
Layer
5
.
In this case left edge support, right edge supports are not considered as fluent flow
solver preference does not consider additional supported solid part. This is the
view of mesh which was generated for the purpose of Fluid Flow Analysis. The
Nodes, Cells and Elements are under the control of limits specified by student
version.
Mesh
Solver
Preference
Fluent
Smoothening Medium
Span Angle
Centre
Coarse
Transition Fast
Transition
Ration
0.272
Maximum
Layer
5
Growth Rate
(Inflation)
1.2
Growth Rate
(Sizing)
1.85
Modified Configurations:
Fluid
Method
Added
Multizone
Mesh
Mapped
Type
Hexa/Prism
Maximum
Edge Length
342.97mm
Nodes 276344
Elements 436459

21
4. MATHEMATICAL MODELING
CALCULATION AT 75 BAR PRESSURE AND 170 ºC (443.15K) TEMPERATURE
Medium Liquid/Fluid
Pressure 75 Bar = 7500000 Pascal
Temperature 170 deg C = 443.15K
Density 901.62338691516 kg / m3
Dynamic viscosity (µ) 0.00016121525392232 Pa s
Specific isobar Heat capacity Cp: 4.3435505375871 KJ/KgK = 4380.7635684103 J/KgK
Thermal conductivity of Fluid 0.68201698396062 W / m K
Boiler Tube Outer Diameter 114.30mm =0.11430m
Boiler Tube Inner Diameter (Hydrodynamic Diameter) 109.17mm = 0.10917m
Boiler Tube Thickness 5.130mm=0.00513m
Boiler Tube Length 4000mm = 4m
Boiler Tube Material’s Thermal Conductivity 52 W/mK
Boiler Tube Material’s Specific Heat (Cp) 460.548 J/Kg K
Boiler Tube Material’s Heat Transfer Coefficient 910 W/m2 K
Boiler Tube Material’s Density 6800 Kg/m3
Boiler Tube Material’s Absolute Roughness (e) 260𝑚𝑖𝑐𝑟𝑜𝑛 =0.00026𝑚𝑒𝑡𝑒𝑟
Velocity 2m/s
Furnace Temperature 200 ºC (473.15K), 300 ºC (573.15K), 400 ºC (673.15K), 500 ºC (773.15K)

22
• Relative roughness =
𝑒
𝐷
260𝑚𝑖𝑐𝑟𝑜𝑛
=
0.10917𝑚
𝑒 0.00026𝑚𝑒𝑡𝑒𝑟
= =
𝐷 0.10917𝑚𝑒𝑡𝑒𝑟
= 0.002381607
Where, e - Absolute roughness
D - Inside diameter of pipe / Hydraulic Diameter
• Reynolds Number, Re =
⍴𝑣𝐷
µ
901.62338691516 ∗ 2 ∗ 0.10917
=
0.00016121525392232
= 1221103.125
Where, ⍴ - fluid density
V- fluid velocity
D- pipe diameter/Hydraulic Diameter
µ- dynamic fluid viscosity
• Friction Factor, f = 0.0055 ( 1 + (2 * 104
* e/D + 106
/Re)1/3
)
= 0.0055 ( 1 + (2 * 104
* 0.00026/0.10917 + 106
/1122912.943)1/3
)
=0.025550743
• Volumetric flow rate = Cross- sectional area * Flow velocity
= π ∗ (
𝐷
)2 * 2
2
= π * (
0.10917
)2 *2
2
= 0.018720890 m3/s
= 18.72089027 l/s
• Mass Flow Rate = ⍴ * Cross-sectional area * Flow velocity
= 901.62338691516 * π * (
0.10917
)2 * 2
2
= 16.87919225 kg/s

23
𝑓𝐿𝑉2
• PressureDrop =𝜌𝑔(Δz+ )
𝐷2𝑔
= 𝜌𝑔Δz +𝜌𝑔
𝑓𝐿𝑉2
𝐷2𝑔
𝑓∗𝐿∗𝜌∗𝑉2
= 0 +
𝐷∗2
=
𝐷∗2
0.025543232 ∗ 4 ∗ 901.62338691516∗2∗2
=
0.10917∗2
= 1688.166891 Pascal
𝑓𝐿𝑉2
• PressureatPointB=Pa– 𝜌𝑔(Δz+ )
𝐷2𝑔
= 11000000 -
0.025543232 ∗ 4 ∗ 901.62338691516∗2∗2
0.10917∗2
= 7498311.833 Pascal
𝑓𝐿𝑉2
• PressureatPointC=Pb– 𝜌𝑔(Δz+ )
𝐷2𝑔
= 10998337.37 -
0.025543232 ∗ 4 ∗ 901.62338691516∗2∗2
0.10917∗2
= 7496623.666 Pascal
𝑓𝐿𝑉2
• PressureatPointD=Pc– 𝜌𝑔(Δz+ )
𝐷2𝑔
= 10996674.74 -
0.025543232 ∗ 4 ∗ 901.62338691516∗2∗2
0.10917∗2
= 7494935.499 Pascal
• 𝑓𝐿𝑉2
PressureatPointE=Pd–𝜌𝑔(Δz+ )
𝐷2𝑔
= 10995012.11 -
0.025543232 ∗ 4 ∗ 901.62338691516∗2∗2
0.10917∗2
= 7493247.332 Pascal
• 𝑓𝐿𝑉2
PressureatPointF=Pe–𝜌𝑔(Δz+ )
𝐷2𝑔
= 10993349.48 -
0.025543232 ∗ 4 ∗ 901.62338691516∗2∗2
0.10917∗2
= 7491559.166 Pascal

24
• Heat Flux
→ when furnace temperature is 200 deg C
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(200−170)
q= = -304093.5673W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(300−170)
q= = -1317738.791W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(400−170)
q= = -2331384.016W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(500−170)
q= = -3345029.240W/m2
0.00513
Where, λ is the thermal conductivity of the material
ΔT is the temperature difference across the object
Δx is the distance of heat transfer(the thickness of the object)q- heat flux

25
• Heat Generation Rate
→ when furnace temperature is 200 deg C Q = mCPΔT
Q = 16.87919225 * 4.3435505375871* (200-170)
=2199.468737KJ-K/s
=2199468.737J-K/s
Q = 16.87919225 * 4.3435505375871 * (300-170)
=9531.031195KJ-K/s
=9531031.195J-K/s
Q = 16.87919225 * 4.3435505375871 * (400-170)
=16862.59365KJ-K/s
=16862593.65J-K/s
Q = 16.87919225 * 4.3435505375871 * (500-170)
=24194.15611KJ-K/s
=24194156.11J-K/s
Where, Q = Heat generation ratem = mass flow rate
CP=Specificheat capacity ΔT = Temperature
difference

26
Medium Liquid/Fluid
Density 891.92900226905kg / m3
Specific isobar heat capacity (Cp): 4.3731627551477 KJ/KgK = 4373.1627551477 J/KgK
Velocity 2m/s

27
𝑒
𝐷
=
0.10917𝑚
= =
= 0.002381607
⍴𝑣𝐷
µ
891.92900226905 ∗ 2 ∗ 0.10917
=
0.0001519874176671
= 1281315.133
V- fluid velocity
* k/D + 106
/Re)1/3
)
= 0.0055 ( 1 + (2 * 104
* 0.00026/0.10917 + 106
/1122912.943)1/3
)
=0.025545433
= π ∗ (
𝐷
)2 * 2
2
= π * (
0.10917
)2 *2
2
= 0.018720890 m3/s
= 18.72089027 l/s
= 891.92900226905 * π * (
0.10917
)2 * 2
2
= 16.69770474 kg/s

28
𝑓𝐿𝑉2
𝐷2𝑔
𝑓𝐿𝑉2
𝐷2𝑔
= 0 +
𝐷∗2
=
𝐷∗2
0.025543232 ∗ 4 ∗ 891.92900226905∗2∗2
=
0.10917∗2
= 1669.668412Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 11000000 -
0.025543232 ∗ 4 ∗ 891.92900226905∗2∗2
0.10917∗2
= 8498330.332 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 10998337.37 -
0.025543232 ∗ 4 ∗ 891.92900226905∗2∗2
0.10917∗2
= 8496660.663 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 10996674.74 -
0.025543232 ∗ 4 ∗ 891.92900226905∗2∗2
0.10917∗2
= 8494990.995 Pascal
𝑓𝐿𝑉2
• PressureatPointE=Pd –𝜌𝑔(Δz+ )
𝐷2𝑔
= 10995012.11 -
0.025543232 ∗ 4 ∗ 891.92900226905∗2∗2
0.10917∗2
= 8493321.326 Pascal
• 𝑓𝐿𝑉2
𝐷2𝑔
= 10993349.48 -
0.025543232 ∗ 4 ∗ 891.92900226905∗2∗2
0.10917∗2
= 8491651.658 Pascal

29
• Heat Flux
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(200−180)
q= = -202729.0448 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(300−180)
q= = -1216374.269 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(400−180)
q= = -2230019.493 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(500−180)
q= = -3243664.717 W/m2
0.00513

30
Q = 16.69770474 * 4.3731627551477 * (200-180)
=1460.435609 KJ-K/s
=1460435.609 J-K/s
Q = 16.69770474 * 4.3731627551477 * (300-180)
=8762.613656 KJ-K/s
=8762613.656 J-K/s
Q = 16.69770474 * 4.3731627551477 * (400-180)
=16064.79170 KJ-K/s
=16064791.70 J-K/s
Q = 16.69770474 * 4.3731627551477 * (500-180)
=23366.96975 KJ-K/s
=23366969.75 J-K/s
difference

31
Medium Liquid/Fluid
Density 888.24652012056 kg / m3
Specific isobar heat capacity Cp: 4.3807635684103 KJ/KgK = 4380.7635684103 J/KgK
Velocity 2m/s

32
𝑒
𝐷
=
0.10917𝑚
= =
= 0.002381607
⍴𝑣𝐷
µ
888.24652012056 ∗ 2 ∗ 0.10917
=
0.00014826717479154
= 1308042.358
V- fluid velocity
* k/D + 106
/Re)1/3
)
= 0.0055 ( 1 + (2 * 104
* 0.00026/0.10917 + 106
/1122912.943)1/3
)
=0.025543232
= π ∗ (
𝐷
)2 * 2
2
= π * (
0.10917
)2 *2
2
= 0.018720890 m3/s
= 18.72089027 l/s
= 888.24652012056 * π * (
0.10917
)2 * 2
2
= 16.62876540 kg/s

33
𝑓𝐿𝑉2
𝐷2𝑔
𝑓𝐿𝑉2
𝐷2𝑔
= 0 +
𝐷∗2
=
𝐷∗2
0.025543232 ∗ 4 ∗ 888.24652012056∗2∗2
=
0.10917∗2
= 1662.631634 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 11000000 -
0.025543232 ∗ 4 ∗ 888.24652012056∗2∗2
0.10917∗2
= 10998337.37 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 10998337.37 -
0.025543232 ∗ 4 ∗ 888.24652012056∗2∗2
0.10917∗2
= 10996674.74 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 10996674.74 -
0.025543232 ∗ 4 ∗ 888.24652012056∗2∗2
0.10917∗2
= 10995012.11 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 10995012.11 -
0.025543232 ∗ 4 ∗ 888.24652012056∗2∗2
0.10917∗2
= 10993349.48 Pascal
• 𝑓𝐿𝑉2
𝐷2𝑔
= 10993349.48 -
0.025543232 ∗ 4 ∗ 888.24652012056∗2∗2
0.10917∗2
= 10991686.84 Pascal

34
• Heat Flux
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(200−185)
q= = -152046.7836 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(300−185)
q= = -1165692.008 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(400−185)
q= = -2179337.232 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(500−185)
q= = -3192982.456 W/m2
0.00513

35
Q = 16.62876540 * 4.3807635684103 * (200-185)
=1092.700345 KJ-K/s
=1092700.345 J-K/s
Q = 16.62876540 * 4.3807635684103 * (300-185)
=8377.369310 KJ-K/s
=8377369.310 J-K/s
Q = 16.62876540 * 4.3807635684103 * (400-185)
=15662.03828 KJ-K/s
=15662038.28 J-K/s
Q = 16.62876540 * 4.3807635684103 * (500-185)
=22946.70724 KJ-K/s
=22946707.24 J-K/s
difference

36
CALCULATION AT 125 BAR PRESSURE AND 195 DEG C (468.15K) TEMPERATURE
Medium Liquid/Fluid
Density 878.36020803597 kg / m3
Specific isobar heat capacity Cp: 4.4130143256588 KJ/KgK =4413.0143256588 J/KgK
Velocity 2m/s

37
𝑒
𝐷
=
0.10917𝑚
= =
= 0.002381607
⍴𝑣𝐷
µ
878.36020803597 ∗ 2 ∗ 0.10917
=
0.00014067817551177
= 1363261.694
V- fluid velocity
* k/D + 106
/Re)1/3
)
= 0.0055 ( 1 + (2 * 104
* 0.00026/0.10917 + 106
/1122912.943)1/3
)
=0.025543232
= π ∗ (
𝐷
)2 * 2
2
= π * (
0.10917
)2 *2
2
= 0.018720890 m3/s
= 18.72089027 l/s
= 878.36020803597 * π * (
0.10917
)2 * 2
2
= 16.43534882 kg/s

38
𝑓𝐿𝑉2
𝐷2𝑔
𝑓𝐿𝑉2
𝐷2𝑔
= 0 +
𝐷∗2
=
𝐷∗2
0.025543232 ∗ 4 ∗ 878.36020803597 ∗2∗2
=
0.10917∗2
= 1644.126304 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 12500000 -
0.025543232 ∗ 4 ∗ 878.36020803597 ∗2∗2
0.10917∗2
= 12498355.87 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 12498355.87 -
0.025543232 ∗ 4 ∗ 878.36020803597 ∗2∗2
0.10917∗2
= 12496711.74 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 12496711.74 -
0.025543232 ∗ 4 ∗ 878.36020803597 ∗2∗2
0.10917∗2
= 12495067.61 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 12495067.61 -
0.025543232 ∗ 4 ∗ 878.36020803597 ∗2∗2
0.10917∗2
= 12493423.48 Pascal
• 𝑓𝐿𝑉2
𝐷2𝑔
= 12493423.48 -
0.025543232 ∗ 4 ∗ 878.36020803597 ∗2∗2
0.10917∗2
= 12491779.35 Pascal

39
• Heat Flux
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(200−195)
q= = -50682.26121 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(300−195)
q= = -1064327.485 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(400−195)
q= = -2077972.71 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(500−195)
q= = -3091617.934 W/m2
0.00513

40
Q = 16.43534882 * 4.4130143256588 * (200-195)
=362.6471489 KJ-K/s
=362647.1489 J-K/s
Q = 16.43534882 * 4.4130143256588 * (300-195)
=7615.590128 KJ-K/s
=7615590.128 J-K/s
Q = 16.43534882 * 4.4130143256588 * (400-195)
=14868.53311 KJ-K/s
=14868533.11 J-K/s
Q = 16.43534882 * 4.4130143256588 * (500-195)
=2212.47609 KJ-K/s
=2212476.09 J-K/s
difference

41
Medium Liquid/Fluid
Density 809.13947917281 kg / m3
Dynamic viscosity 0.000108630917281 Pa s
Specific isobar heat capacity Cp: 4.7518247461102 KJ/KgK =4751.8247461102J/Kg
Thermal Conductivity of Fluid 0.63262571716916 W / m K
Boiler Tube Inner Diameter (Hydrodynamic
Diameter)
109.17mm = 0.10917m
Velocity 2m/s

42
𝑒
𝐷
=
0.10917𝑚
= =
= 0.002381607
⍴𝑣𝐷
µ
809.13947917281 ∗ 2 ∗ 0.10917
=
0.000108630917281
= 148807456
V- fluid velocity
* k/D + 106
/Re)1/3
)
= 0.0055 ( 1 + (2 * 104
* 0.00026/0.10917 + 106
/1122912.943)1/3
)
=0.025543232
= π ∗ (
𝐷
)2 * 2
2
= π * (
0.10917
)2 *2
2
= 0.018720890 m3/s
= 18.72089027 l/s
= 809.13947917281* π * (
0.10917
)2 * 2
2
= 15.14 kg/s

43
𝑓𝐿𝑉2
𝐷2𝑔
𝑓𝐿𝑉2
𝐷2𝑔
= 0 +
𝐷∗2
=
𝐷∗2
0.025543232 ∗ 4 ∗ 809.13947917281∗2∗2
=
0.10917∗2
= 1325.304085 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 13200000 -
0.025543232 ∗ 4 ∗ 809.13947917281∗2∗2
0.10917∗2
= 13198674.7 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 13198674.7 -
0.025543232 ∗ 4 ∗ 809.13947917281∗2∗2
0.10917∗2
= 13147349.39 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 13147349.39 -
0.025543232 ∗ 4 ∗ 809.13947917281∗2∗2
0.10917∗2
= 13196024.09 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 13196024.09 -
0.025543232 ∗ 4 ∗ 809.13947917281∗2∗2
0.10917∗2
= 13194698.78 Pascal
• 𝑓𝐿𝑉2
𝐷2𝑔
= 13194698.78 -
0.025543232 ∗ 4 ∗ 809.13947917281∗2∗2
0.10917∗2
= 13193373.48 Pascal

44
• Heat Flux
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(200−250)
q= = -506822.6121 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(300−250)
q= = -506822.6121 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(400−250)
q= = -1520467.836 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(500−250)
q= = -2534113.06 W/m2
0.00513

45
Q = 15.14 * 4.7518247461102 * (200-250)
=-3597.131333 KJ-K/s
=-3597131.333 J-K/s
Q = 15.14 * 4.7518247461102 * (300-250)
=3597.131333 KJ-K/s
=3597131.333 J-K/s
Q = 15.14 * 4.7518247461102 * (400-250)
=10791.394 KJ-K/s
=10791394 J-K/s
Q = 15.14 * 4.7518247461102 * (500-250)
=17985.65666 KJ-K/s
=17985656.66 J-K/s
difference

46
Medium Liquid/Fluid
Density 762.11364427538 kg / m3
Dynamic viscosity 0.00009593266098552 Pa s
Specific isobar heat capacity Cp: 5.1037054737142 KJ/KgK=5103.7054737142 J/Kgk
Thermal Conductivity of Fluid 0.59407745640301 W / m K
Diameter)
109.17mm = 0.10917m
Velocity 2m/s

47
𝑒
𝐷
=
0.10917𝑚
= =
= 0.002381607
⍴𝑣𝐷
µ
762.11364427538 ∗ 2 ∗ 0.10917
=
0.00009593266098552
= 1734548.916
V- fluid velocity
* k/D + 106
/Re)1/3
)
f = 0.0055 ( 1 + (2 * 104
* 0.00026/0.10917 + 106
/1122912.943)1/3
)
f=0.025543232
= π ∗ (
𝐷
)2 * 2
2
= π * (
0.10917
)2 *2
2
= 0.018720890 m3/s
= 18.72089027 l/s
= 762.11364427538* π * (
0.10917
)2 * 2
2
= 14.26021292 kg/s

48
𝑓𝐿𝑉2
𝐷2𝑔
𝑓𝐿𝑉2
𝐷2𝑔
= 0 +
𝐷∗2
=
𝐷∗2
0.025543232 ∗ 4 ∗ 762.11364427538∗2∗2
=
0.10917∗2
= 1373.856968 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 14000000 -
0.025543232 ∗ 4 ∗ 762.11364427538∗2∗2
0.10917∗2
= 13998626.14 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 13998626.14 -
0.025543232 ∗ 4 ∗ 762.11364427538∗2∗2
0.10917∗2
= 13997252.28 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 1399725.28 -
0.025543232 ∗ 4 ∗ 762.11364427538∗2∗2
0.10917∗2
= 13995878.42 Pascal
𝑓𝐿𝑉2
𝐷2𝑔
= 13995878.42 -
0.025543232 ∗ 4 ∗ 762.11364427538∗2∗2
0.10917∗2
= 13994504.56 Pascal
• 𝑓𝐿𝑉2
𝐷2𝑔
= 13994504.56 -
0.025543232 ∗ 4 ∗762.11364427538∗2∗2
0.10917∗2
= 13993130.7 Pascal

49
• Heat Flux
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(200−280)
q= = 810916.1793 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(300−280)
q= = -202729.0448 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(400−280)
q= = -1216374.269 W/m2
0.00513
−𝜆𝛥𝑇
q =
𝛥𝑥
−52∗(500−280)
q= = -22300019.493 W/m2
0.00513

50
Q = 14.26021292 * 5.1037054737142 * (200-280)
=-5822.394139 KJ-K/s
=-5822394.139 J-K/s
Q = 14.26021292 * 5.1037054737142 * (300-280)
=1455.598535 KJ-K/s
=1455598.535 J-K/s
Q = 14.26021292 * 5.1037054737142 * (400-280)
=8733.591208 KJ-K/s
=8733591.208 J-K/s
Q = 14.26021292 * 5.1037054737142 * (500-280)
=16011.58388 KJ-K/s
=16011583.88 J-K/s
difference

51
P=S[
2𝑡−0.01𝐷−2𝑒
𝐷−(𝑡−0.005𝐷−𝑒)
]
→CALCULATION OF MAXIMUM ALLOWABLE PRESSURE
Minimum Design Wall Thickness (t) 5.130mm = 0.00513m = 0.2019685039 in
Tube Outside Diameter (D) 114.30mm = 0.1143m = 4.5 in
Maximum Allowable Stress (40 deg C – 381 deg C) 108 MPa = 15664.075675 psi
Maximum Allowable Stress (405 deg C–412 deg C) 105 Mpa = 15228.962462 psi
Maximum Allowable Stress (413 deg C–420 deg C) 104 Mpa =15083.924724 psi
Maximum Allowable Stress (450 deg C) 101 Mpa = 14648.811511 psi
Maximum Allowable Stress (550 deg C) 23.6Mpa = 3422.8906104 psi
→ According to ASME Boiler Tubes up to and including O.D. of 125 mm
→ For considering Maximum Allowable Stress at different temperature we referred online ASME maximum
allowablestresstable[Link:https://www.cis-inspector.com/asme-code-allowable-stresses-table-1a.htm]
&findthecommonsuitablematerialSA334havingcommonmechanicalpropertiesasthatofBS3059:
Part 1: 1987ERW320
→To Calculate the Maximum Allowable Working Pressure (MAWP):
Where:
t = Minimum Design Wall Thickness (in);
P = Design Pressure (psi);
D = Tube outside Diameter (in);
e = Thickness Factor (0.04 for expanded tubes; 0 = for strength welded tubes);
S = Maximum Allowable Stress According to ASME Section II.
→To Calculate the Maximum Allowable Working Pressure (MAWP) between 40 deg C – 381 deg C
Maximum Allowable Stress (S): 108 MPa = 15664.075675 psi
P = 15664.075675 * [
2∗0.2019685039 −0.01∗4.5−2∗0
]
4.5−(0.2019685039−0.005∗4.5−0)
P = 1243.063741 psi = 8570622.7941 Pascal

52
→To Calculate the Maximum Allowable Working Pressure (MAWP) between 405 deg C–412 deg C
Maximum Allowable Stress (S): 105 Mpa = 15228.962462 psi
P = 15228.962462* [
2∗0.2019685039 −0.01∗4.5−2∗0
]
4.5−(0.2019685039−0.005∗4.5−0)
P = 1208.534193 psi = 8332549.9412 Pascal
→To Calculate the Maximum Allowable Working Pressure (MAWP) between 413 deg C – 420 deg C
Maximum Allowable Stress (S): 104 Mpa =15083.924724 psi
P = 15083.924724 * [
2∗0.2019685039 −0.01∗4.5−2∗0
]
4.5−(0.2019685039−0.005∗4.5−0)
P = 1197.024343 psi = 8253192.319 Pascal
→To Calculate the Maximum Allowable Working Pressure (MAWP) between 450 deg C
Maximum Allowable Stress (S): 101 Mpa = 14648.811511 psi
P = 14648.811511 * [
2∗0.2019685039 −0.01∗4.5−2∗0
]
4.5−(0.2019685039−0.005∗4.5−0)
P = 1162.494795 psi = 8015119.4661 Pascal
→To Calculate the Maximum Allowable Working Pressure (MAWP) between 500 deg C
Maximum Allowable Stress (S): 23.6Mpa = 3422.8906104 psi
P = 3422.8906104 * [
2∗0.2019685039 −0.01∗4.5−2∗0
]
4.5−(0.2019685039−0.005∗4.5−0)
P = 271.6324471 psi = 1872839.7957 Pascal

53
THERMAL ANALYSIS
Overheating and excessive thermal stresses are some of the issues related to heat
transfer that a thermal analyst has to consider. Thermal analysis can be executed to
find temperature distribution, temperature gradient, and heat flowing in the model,
as well as the heat exchanged between the model and its environment. Good thermal
assessments require a combination of analytical calculations using thermal
specifications, empirical analysis and thermal modeling. The art of thermal analysis
involves using all available tools to support each other and validate their
conclusions. Applying three different and sometimes complex thermal transport
mechanisms to a complex thermal product creates a system that
cannot be evaluated by simple and inexpensive tools. Often the
only feasible approach is to model such a product with tools created
for that purpose and validate that model with empirical testing. Since there are many
parameters that affect the temperature of a product, and various ways of heat transfer
involved, it takes cutting edge CAE software to undertake thermal analysis.
In the research paper “Understanding Boiler Circulation” which was published by
the author Viswanathan Ganapathy where in his final thoughts he mentioned that
"Many plant engineers review information such as construction details, painting,
duct thickness, structural integrity, code documents and so on, but few review the
boiler’s thermal performance calculations, drum baffling system details or thermal
performance and circulation issues. However, engineers should review these things
before buying a new boiler plant, using either in-house expertise or third-party
consultants." Thermal Analysis Should be Done in order to analyze and review the
thermal performance of the boiler tube considering different practical conditions in
analytical way. Therefore for the purpose of thermal analysis on the boiler tube
steady state thermal system of workbench was selected from the toolbox provided
and used for the purpose. Under this toolbox Ansys offers thermal analysis software
solutions that enable engineers of all levels and backgrounds to solve complex
structural engineering problems faster and more efficiently.

54
THERMAL ANALYSIS AT 170 ºC (443.15K) INNER TUBE TEMPERATURE
Thermal
Conductivity
Tempera
ture
From
Furnace
Temperatu
re Inside
Tube
Thickne
ss of the
Object
Heat
Transfer
Coefficie
nt
Area Heat Flux
Convective Heat
Transfer
52 W/mK 500 ºC 170 ºC
0.00513
m
910 W/
m2 K
7.13881 m2
-
3345029.240W/
m2
2144142.00 W
52 W/mK 400 ºC 170 ºC
0.00513
m
910 W/
m2 K
7.13881 m2
-
2331384.016W/
m2
1494402.00 W
52 W/mK 300 ºC 170 ºC
0.00513
m
910 W/
m2 K
7.13881 m2
-
1317738.791W/
m2
844662.00 W
52 W/mK 200 ºC 170 ºC
0.00513
m
910 W/
m2 K
7.13881 m2
-
304093.5673W/
m2
194922.00 W
Based on the calculated boundary conditions thermal analysis has been done and considering
170 deg C inner tube temperature and parameters like convection, convective heat transfer,
thermal conductivity, and thickness has been used to find out and implement the correct
boundary conditions. In this analysis the heat from the furnace has been considered to find out
the heat flux value & the temperature difference of 200 deg C has been observed. The results
obtained from the thermal analysis are not sufficient to find out or to pre visualize the actual
practical condition to get the insight. Therefore fluid flow pressure analysis is required to
performed under the fluent library of Ansys workbench. This thermal analysis has been
performed under steady state thermal library. Transient Thermal analysis is not used in this
analysis to keep the conditions simple.

55
THERMAL ANALYSIS 180 ºC (453.15K) INNER TUBE TEMPERATURE
Thermal
Conductivity
Tempera
ture
From
Furnace
Temperatu
re Inside
Tube
Thickne
ss of the
Object
Heat
Transfer
Coefficie
nt
Area Heat Flux
Convective Heat
Transfer
52 W/mK 500 ºC 180 ºC
0.00513
m
910 W/
m2 K 7.13881 m2
-3243664.717
W/m2 2079168.00 W
52 W/mK 400 ºC 180 ºC
0.00513
m
910 W/
m2 K 7.13881 m2
-2230019.493
W/m2 1429428.00 W
52 W/mK 300 ºC 180 ºC
0.00513
m
910 W/
m2 K 7.13881 m2
-1216374.269
W/m2 779688.00 W
52 W/mK 200 ºC 180 ºC
0.00513
m
910 W/
m2 K 7.13881 m2
-202729.0448
W/m2 129948.00 W
Based on the calculated boundary conditions thermal analysis has been done and
considering 180 deg C inner tube temperature and parameters like convection,
convective heat transfer, thermal conductivity, and thickness has been used to find
out and implement the correct boundary conditions. In this analysis the heat from the
furnace has been considered to find out the heat flux value & the temperature
difference of 300 deg C has been observed. The results obtained from the thermal
analysis are not sufficient to find out or to pre visualize the actual practical condition
to get the insight. Therefore fluid flow pressure analysis is required to performed
under the fluent library of Ansys workbench. This thermal analysis has been
performed under steady state thermal library. Transient Thermal analysis is not used
in this analysis to keep the conditions simple.

56
THERMAL ANALYSIS AT 185 ºC (458.15K) INNER TUBE TEMPERATURE
Thermal
Conductivity
Tempera
ture
From
Furnace
Temperatu
re Inside
Tube
Thickne
ss of the
Object
Heat
Transfer
Coefficie
nt
Area Heat Flux
Convective Heat
Transfer
52 W/mK 500 ºC 185 ºC
0.00513
m
910 W/
m2 K 7.13881 m2
-3192982.456
W/m2 2046681.00 W
52 W/mK 400 ºC 185 ºC
0.00513
m
910 W/
m2 K 7.13881 m2
-2179337.232
W/m2 1396941.00 W
52 W/mK 300 ºC 185 ºC
0.00513
m
910 W/
m2 K 7.13881 m2
-1165692.008
W/m2 747201.00 W
52 W/mK 200 ºC 185 ºC
0.00513
m
910 W/
m2 K 7.13881 m2
-152046.7836
W/m2 97461.00 W
Based on the calculated boundary conditions thermal analysis has been done and
considering 185 deg C inner tube temperature and parameters like convection,
convective heat transfer, thermal conductivity, and thickness has been used to find
out and implement the correct boundary conditions. In this analysis the heat from the
furnace has been considered to find out the heat flux value & the temperature
difference of 500 deg C has been observed. The results obtained from the thermal
analysis are not sufficient to find out or to pre visualize the actual practical condition
to get the insight. Therefore fluid flow pressure analysis is required to performed
under the fluent library of Ansys workbench. This thermal analysis has been
performed under steady state thermal library. Transient Thermal analysis is not used
in this analysis to keep the conditions simple.

57
FLUID FLOW PRESSURE ANALYSIS
Fluid flow pressure analysis is required to observe the insight of fluid flow pattern of fluid at
different conditions inside the boiler tube and to know about the impact of temperature on the
fluid flow pressure pattern and to know about the impact on wall solid of boiler tube due to the
fluid flow pressure when subjected to high temperatures.
In order to perform the fluid flow pressure analysis & to get the actual insight of the fluid flow
there is requirement of practical conditions which actually exist inside the boiler tubes. To obtain
the practical conditions journals and research paper has to be referred. There are multiple
research papers available for the consideration of experimental input data but for selecting the
experimental input data, the boiler type set-up has to be finalized because data varies as per as
the type of Boiler. Therefore Lamont boiler set-up type is selected for the purpose and
accordingly data has been referred from the research papers and journals. Therefore for the
purpose of fluid flow pressure analysis on the wall solid of the boiler tube fluid flow fluent
system of workbench was selected from the toolbox provided and used for the purpose. Under
this toolbox Ansys offers fluid flow analysis software solutions that enable engineers of all levels
and backgrounds to solve complex structural engineering problems faster and more efficiently.
The fluid flow pressure analysis was performed on multiple conditions but significant results has
been observed on the following three conditions i.e., first condition was 75 bar pressure, 110°C
inlet feed water temperature and 500°C flue gas temperature, second condition was 85 Bar
Pressure, 180°C feed water temperature, third condition was 110Bar Pressure, 185°C inlet water
temperature and 500°C flue gas temperature from the furnace has been taken. For making
Analysis at each conditions contours of total fluid pressure has been recorded after initialing &
running calculations at equal intervals of iterations. The implementation of the turbulent flow has
been done by using this and this data After performing the fluid flow pressure analysis at this
condition it has been noted that the contours of fluid flow pressure is showing negative impact as
the iterations follows i.e., in first 10 iterations it has been observed that the bottom part of the
fluid is showing the maximum negative impact and the upper part is showing the minimum
negative impact.

58
AT 75 BAR PRESSURE AND 110ºC INLET TEMPERATURE
Medium Liquid/Fluid
Density 901.62338691516 kg / m3
Specific isobar Heat capacity Cp: 4.3435505375871 KJ/KgK =
4380.7635684103 J/KgK
Diameter)
109.17mm = 0.10917m
Velocity 2m/s
Furnace Temperature 200 ºC (473.15K), 300 ºC (573.15K), 400 ºC (673.15K), 500 ºC
(773.15K)
CALCULATED BOUNDARY CONDITIONS 75 BAR PRESSURE AND 170 ºC (443.15K)
TEMPERATURE
Relative roughness 0.002381607 (m/m)
Reynolds Number 1221103.125
Friction Factor 0.025550743
Volumetric Flow Rate 0.018720890 m3/s = 18.72089027 l/s
Mass Flow Rate 16.87919225 kg/s
Pressure Drop 1688.166891 Pascal
Pressure at Point B 7498311.833 Pascal
Pressure at Point C 7496623.666 Pascal
Pressure at Point D 7494935.499 Pascal
Pressure at Point E 7493247.332 Pascal
Pressure at Point F 7491559.166 Pascal
Heat Flux -2331384.016W/m2

59
The contours of fluid flow pressure pattern has been generated at 75 Bar pressure
and 170ºC with the consideration, calculation and implementation of the required boundary
conditions i.e., Pressure, Temperature, Density, Dynamic viscosity (µ), Specific isobar heat
capacity (Cp), Thermal conductivity of Fluid, Velocity, Heat flux.
The contours are recorded at the interval of 10 iterations, which was manually divided in
3600 seconds According to the generated contours the successful simulation of the fluid flow
behavior was developed and analyzed. The long intervals of iterations were not considered
due to the limitations of processor used.

Study and Analysis of Tube Failure in Water Tube boiler

Study and Analysis of Tube Failure in Water Tube boiler

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