A shell and tube heat exchanger was designed to raise the temperature of fresh water from 40°C to 50°C using waste water at 80°C. Analytical calculations determined a heat transfer area of 0.7 m2 was required. CFD simulation validated the design, showing the fresh water temperature increased as required while the waste water temperature dropped by the calculated amount. The CFD determined heat transfer coefficient was within 3% of the theoretical value, validating the design calculations.
Design Considerations for Plate Type Heat ExchangerArun Sarasan
A plate heat exchanger is a type of heat exchanger that uses metal plates to transfer heat between two fluids. This has a major advantage over a conventional heat exchanger in that the fluids are exposed to a much larger surface area because the fluids spread out over the plates. This facilitates the transfer of heat, and greatly increases the speed of the temperature change. Plate heat exchangers are now common and very small brazed versions are used in the hot-water sections of millions of combination boilers. The high heat transfer efficiency for such a small physical size has increased the domestic hot water (DHW) flowrate of combination boilers. The small plate heat exchanger has made a great impact in domestic heating and hot-water. Larger commercial versions use gaskets between the plates, whereas smaller versions tend to be brazed.
Parallel flow heat exchanger is analysed with CFD tool. A comparative study of the analytical and experimental data is carried out to better understand the temperature profile, surface heat flux and heat transfer co-efficient parameters of the heat exchanger
DESIGN AND FABRICATION OF HELICAL TUBE IN COIL TYPE HEAT EXCHANGERhemantnehete
Heat exchangers are the important engineering systems with wide variety of applications including power plants, nuclear reactors, refrigeration and air-conditioning systems, heat recovery systems, chemical processing and food industries. Helical coil configuration is very effective for heat exchangers and chemical reactors because they can accommodate a large heat transfer area in a small space, with high heat transfer coefficients. This project focus on an increase in the effectiveness of a heat exchanger and analysis of various parameters that affect the effectiveness of a heat exchanger and also deals with the performance analysis of heat exchanger by varying various parameters like number of coils, flow rate and temperature. The results of the helical tube heat exchanger are compared with the straight tube heat exchanger in both parallel and counter flow by varying parameters like temperature, flow rate of cold water and number of turns of helical coil.
Heat transfer from extended surfaces (or fins)tmuliya
This file contains slides on Heat Transfer from Extended Surfaces (FINS). The slides were prepared while teaching Heat Transfer course to the M.Tech. students in Mechanical Engineering Dept. of St. Joseph Engineering College, Vamanjoor, Mangalore, India.
Contents: Governing differential eqn – different boundary conditions – temp. distribution and heat transfer rate for: infinitely long fin, fin with insulated end, fin losing heat from its end, and fin with specified temperatures at its ends – performance of fins - ‘fin efficiency’ and ‘fin effectiveness’ – fins of non-uniform cross-section- thermal resistance and total surface efficiency of fins – estimation of error in temperature measurement - Problems
Design Considerations for Plate Type Heat ExchangerArun Sarasan
A plate heat exchanger is a type of heat exchanger that uses metal plates to transfer heat between two fluids. This has a major advantage over a conventional heat exchanger in that the fluids are exposed to a much larger surface area because the fluids spread out over the plates. This facilitates the transfer of heat, and greatly increases the speed of the temperature change. Plate heat exchangers are now common and very small brazed versions are used in the hot-water sections of millions of combination boilers. The high heat transfer efficiency for such a small physical size has increased the domestic hot water (DHW) flowrate of combination boilers. The small plate heat exchanger has made a great impact in domestic heating and hot-water. Larger commercial versions use gaskets between the plates, whereas smaller versions tend to be brazed.
Parallel flow heat exchanger is analysed with CFD tool. A comparative study of the analytical and experimental data is carried out to better understand the temperature profile, surface heat flux and heat transfer co-efficient parameters of the heat exchanger
DESIGN AND FABRICATION OF HELICAL TUBE IN COIL TYPE HEAT EXCHANGERhemantnehete
Heat exchangers are the important engineering systems with wide variety of applications including power plants, nuclear reactors, refrigeration and air-conditioning systems, heat recovery systems, chemical processing and food industries. Helical coil configuration is very effective for heat exchangers and chemical reactors because they can accommodate a large heat transfer area in a small space, with high heat transfer coefficients. This project focus on an increase in the effectiveness of a heat exchanger and analysis of various parameters that affect the effectiveness of a heat exchanger and also deals with the performance analysis of heat exchanger by varying various parameters like number of coils, flow rate and temperature. The results of the helical tube heat exchanger are compared with the straight tube heat exchanger in both parallel and counter flow by varying parameters like temperature, flow rate of cold water and number of turns of helical coil.
Heat transfer from extended surfaces (or fins)tmuliya
This file contains slides on Heat Transfer from Extended Surfaces (FINS). The slides were prepared while teaching Heat Transfer course to the M.Tech. students in Mechanical Engineering Dept. of St. Joseph Engineering College, Vamanjoor, Mangalore, India.
Contents: Governing differential eqn – different boundary conditions – temp. distribution and heat transfer rate for: infinitely long fin, fin with insulated end, fin losing heat from its end, and fin with specified temperatures at its ends – performance of fins - ‘fin efficiency’ and ‘fin effectiveness’ – fins of non-uniform cross-section- thermal resistance and total surface efficiency of fins – estimation of error in temperature measurement - Problems
Numerical methods in Transient-heat-conductiontmuliya
This file contains slides on Numerical methods in Transient heat conduction.
The slides were prepared while teaching Heat Transfer course to the M.Tech. students in Mechanical Engineering Dept. of St. Joseph Engineering College, Vamanjoor, Mangalore, India, during Sept. – Dec. 2010.
Contents: Finite difference eqns. by energy balance – Explicit and Implicit methods – 1-D transient conduction in a plane wall – stability criterion – Problems - 2-D transient heat conduction – Finite diff. eqns. for interior nodes – Explicit and Implicit methods - stability criterion – difference eqns for different boundary conditions – Accuracy considerations – discretization error and round–off error - Problems
This file contains slides on NUMERICAL METHODS IN STEADY STATE 1D and 2D HEAT CONDUCTION – Part-I.
The slides were prepared while teaching Heat Transfer course to the M.Tech. students.
Contents: Why Numerical methods? – Advantages – Finite difference formulation from differential eqns – 1D steady state conduction in cartesian coordinates – formulation by energy balance method – different BC’s – Problems
In this paper three different cut patterns of brake disc are studied for heat transfer rate. Heat transfer rate increases with number of cuts in the disc. This is because large area is exposed to air which makes more heat transfer through conduction and convection. But increase in number and size of cuts decreases the strength of disc. And analysed thermally in ANSYS for different material and design created in CREO 3.0.
CFD Analysis of Heat Transfer Enhancement in Shell and Tube Type Heat Exchang...ijtsrd
Shell and Tube heat exchangers are having special importance in boilers, oil coolers, condensers, pre-heaters. Shell and Tube heat exchanger is one such heat exchanger, provides more area for heat transfer between two fluids in comparison with other type of heat exchanger. To intensify heat transfer with minimum pumping power innovative heat transfer fluids called Nano fluids have become the major area of research now a days. The primary aim is to evaluate the effect of different weight concentration and temperatures on convective heat transfer. Increasing the weight concentration and temperatures leads to enhancement of convective heat transfer coefficient. In the present, work attempts are made to enhance the heat transfer rate in shell and tube heat exchangers. A multi pass shell and tube heat exchanger with 3 tubes with fins modelling is done using ANSYS. Nanofluid such as Al2O3-H2O is used. The CFD simulated results achieved from the use of the creating fin in tube side in shell and tube type heat exchanger are compared with without fin. Based on the results, providing fins on tube causes the increment of overall heat transfer coefficient which results in the enhancement of heat transfer rate of heat exchanger. Sudhanshu Pathak | H. S. Sahu"CFD Analysis of Heat Transfer Enhancement in Shell and Tube Type Heat Exchanger creating Triangular Fin on the Tubes" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: http://www.ijtsrd.com/papers/ijtsrd14259.pdf http://www.ijtsrd.com/engineering/mechanical-engineering/14259/cfd-analysis-of-heat-transfer-enhancement-in-shell-and-tube-type-heat-exchanger-creating-triangular-fin-on-the-tubes/sudhanshu-pathak
Experimentation and analysis of heat transfer through perforated fins of diff...SharathKumar528
Engineering Project by Abhijath HB, Dashartha H S, Akshay Mohanraj and Sharath Kumar M S involving analysis of Fins( Heat exchanging extensions) with various geometrical perforations.
In this Thesis I will try to understand the concept associated with cooling towers and model a laboratory sized cooling tower in a software package called Engineering Equation Solver (EES). An example of system modelling is presented in this progress report, along with the comparison of a set of results with an experimental data from P.A Hilton Model H892 Bench top cooling tower with a maximum of 9% error. A user interface is also modelled to simulate off-design performance rather than conducting experiments. It also allows you to do additional scenarios that cannot be practically being done in lab,
like Relative humidity, etc.
Analysis of forced draft cooling tower performance using ansys fluent softwareeSAT Journals
Abstract In this project the cooling tower performance has been analyzed by varying air inlet parameters with different air inlet angles and by attaching a nozzle in air inlet. The cooling tower analyzed here is used specifically for small scale industries, which is forced draft counter-flow cooling tower with single module capacities from 10 to 100 cooling tons. In this project 50 tons cooling capacity model has been taken as reference model. The analysis has been done using computational fluid dynamics (CFD) ANSYS 14.5 software. The cooling tower models have been modeled using SOLIDWORKS 2013 software and they have been meshed using ICEM CFD 14.5 software. The meshed models have been analyzed using FLUENT software. The air inlet angles varied in horizontal direction, vertical direction and by combining both horizontal and vertical inclination. A convergent nozzle has been modeled and assembled to the inlet pipe. The temperature contours of the cooling tower models have been taken from the analysis. Based on the outlet cold water temperature, the improved effectiveness of the cooling tower model has been obtained.
Keywords: Forced draft cooling tower, Air inlet parameter, Convergent nozzle, Cooling ton capacity, Counter flow cooling tower, Ansys 14.5, Solidworks 2013, ICEM CFD 14.5, Effectiveness of cooling tower.
Cfd Simulation and Experimentalverification of Air Flow through Heated PipeIOSR Journals
The aim of this work is to validate the Dittus-Boelter equation by experimental,correlation and Simulation method. It used to find the value of heat transfer coefficient ‘h’ for turbulent flow in many fluid transfer systems. This work discusses how the Dittus-Boelter equation is applied to the problem of circular pipe. In CFD simulation ICEM CFD for modeling and CFX13 for analysis are used. Results of CFD simulation will be obtained by CFD-POST. Here heat transfer coefficient value is compared by correlations,experiment and CFD simulations, finally the aim of this work is to validate Dittus-Boelter equation.
Numerical methods in Transient-heat-conductiontmuliya
This file contains slides on Numerical methods in Transient heat conduction.
The slides were prepared while teaching Heat Transfer course to the M.Tech. students in Mechanical Engineering Dept. of St. Joseph Engineering College, Vamanjoor, Mangalore, India, during Sept. – Dec. 2010.
Contents: Finite difference eqns. by energy balance – Explicit and Implicit methods – 1-D transient conduction in a plane wall – stability criterion – Problems - 2-D transient heat conduction – Finite diff. eqns. for interior nodes – Explicit and Implicit methods - stability criterion – difference eqns for different boundary conditions – Accuracy considerations – discretization error and round–off error - Problems
This file contains slides on NUMERICAL METHODS IN STEADY STATE 1D and 2D HEAT CONDUCTION – Part-I.
The slides were prepared while teaching Heat Transfer course to the M.Tech. students.
Contents: Why Numerical methods? – Advantages – Finite difference formulation from differential eqns – 1D steady state conduction in cartesian coordinates – formulation by energy balance method – different BC’s – Problems
In this paper three different cut patterns of brake disc are studied for heat transfer rate. Heat transfer rate increases with number of cuts in the disc. This is because large area is exposed to air which makes more heat transfer through conduction and convection. But increase in number and size of cuts decreases the strength of disc. And analysed thermally in ANSYS for different material and design created in CREO 3.0.
CFD Analysis of Heat Transfer Enhancement in Shell and Tube Type Heat Exchang...ijtsrd
Shell and Tube heat exchangers are having special importance in boilers, oil coolers, condensers, pre-heaters. Shell and Tube heat exchanger is one such heat exchanger, provides more area for heat transfer between two fluids in comparison with other type of heat exchanger. To intensify heat transfer with minimum pumping power innovative heat transfer fluids called Nano fluids have become the major area of research now a days. The primary aim is to evaluate the effect of different weight concentration and temperatures on convective heat transfer. Increasing the weight concentration and temperatures leads to enhancement of convective heat transfer coefficient. In the present, work attempts are made to enhance the heat transfer rate in shell and tube heat exchangers. A multi pass shell and tube heat exchanger with 3 tubes with fins modelling is done using ANSYS. Nanofluid such as Al2O3-H2O is used. The CFD simulated results achieved from the use of the creating fin in tube side in shell and tube type heat exchanger are compared with without fin. Based on the results, providing fins on tube causes the increment of overall heat transfer coefficient which results in the enhancement of heat transfer rate of heat exchanger. Sudhanshu Pathak | H. S. Sahu"CFD Analysis of Heat Transfer Enhancement in Shell and Tube Type Heat Exchanger creating Triangular Fin on the Tubes" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: http://www.ijtsrd.com/papers/ijtsrd14259.pdf http://www.ijtsrd.com/engineering/mechanical-engineering/14259/cfd-analysis-of-heat-transfer-enhancement-in-shell-and-tube-type-heat-exchanger-creating-triangular-fin-on-the-tubes/sudhanshu-pathak
Experimentation and analysis of heat transfer through perforated fins of diff...SharathKumar528
Engineering Project by Abhijath HB, Dashartha H S, Akshay Mohanraj and Sharath Kumar M S involving analysis of Fins( Heat exchanging extensions) with various geometrical perforations.
In this Thesis I will try to understand the concept associated with cooling towers and model a laboratory sized cooling tower in a software package called Engineering Equation Solver (EES). An example of system modelling is presented in this progress report, along with the comparison of a set of results with an experimental data from P.A Hilton Model H892 Bench top cooling tower with a maximum of 9% error. A user interface is also modelled to simulate off-design performance rather than conducting experiments. It also allows you to do additional scenarios that cannot be practically being done in lab,
like Relative humidity, etc.
Analysis of forced draft cooling tower performance using ansys fluent softwareeSAT Journals
Abstract In this project the cooling tower performance has been analyzed by varying air inlet parameters with different air inlet angles and by attaching a nozzle in air inlet. The cooling tower analyzed here is used specifically for small scale industries, which is forced draft counter-flow cooling tower with single module capacities from 10 to 100 cooling tons. In this project 50 tons cooling capacity model has been taken as reference model. The analysis has been done using computational fluid dynamics (CFD) ANSYS 14.5 software. The cooling tower models have been modeled using SOLIDWORKS 2013 software and they have been meshed using ICEM CFD 14.5 software. The meshed models have been analyzed using FLUENT software. The air inlet angles varied in horizontal direction, vertical direction and by combining both horizontal and vertical inclination. A convergent nozzle has been modeled and assembled to the inlet pipe. The temperature contours of the cooling tower models have been taken from the analysis. Based on the outlet cold water temperature, the improved effectiveness of the cooling tower model has been obtained.
Keywords: Forced draft cooling tower, Air inlet parameter, Convergent nozzle, Cooling ton capacity, Counter flow cooling tower, Ansys 14.5, Solidworks 2013, ICEM CFD 14.5, Effectiveness of cooling tower.
Cfd Simulation and Experimentalverification of Air Flow through Heated PipeIOSR Journals
The aim of this work is to validate the Dittus-Boelter equation by experimental,correlation and Simulation method. It used to find the value of heat transfer coefficient ‘h’ for turbulent flow in many fluid transfer systems. This work discusses how the Dittus-Boelter equation is applied to the problem of circular pipe. In CFD simulation ICEM CFD for modeling and CFX13 for analysis are used. Results of CFD simulation will be obtained by CFD-POST. Here heat transfer coefficient value is compared by correlations,experiment and CFD simulations, finally the aim of this work is to validate Dittus-Boelter equation.
Complex Engineering Problem (CEP) Descriptive Form.
Simultaneous Heat and Mass Transfer.
The concentric tube heat exchanger is replaced with a compact, plate-type heat exchanger that consists of a stack of thin metal sheets, separated by N gaps of width a. The oil and water flows are subdivided into N/2 individual flow streams, with the oil and water moving in opposite directions within alternating gaps. It is desirable for the stack to be of a cubical geometry, with a characteristic exterior dimension L.
(a) parallel flow
(b) counter flow,
A counter flow, concentric tube heat exchanger is used to cool the lubricating oil for a large industrial gas turbine engine. The flow rate of cooling water through the inner tube (Di - 25 mm) is 0.2 kg/s,.
This exercise is intended only as an educational tool to assist those who wish to learn how to use ANSYS for predicting behavior of a linear spring system. It is not
intended to be used as a guide for determining suitable modeling methods for any application
Improving the capture efficiency of fine particles has attracted more attention because of the negative impact of fine particles on human health. In particular, high-efficiency particulate air (HEPA) filters need to be designed to effectively capture ultrafine particles smaller than 300 nm, which is important to produce clean breathable air and also to ensure safety in biosafety laboratories and the nuclear industry.
This PPT illustrates a sample procedure as per fluent to simulate flow through pleated filters using porus media concept .
A fuel cell uses the chemical energy of hydrogen or another fuel to cleanly and efficiently produce electricity. If hydrogen is the fuel, electricity, water, and heat are the only products. Fuel cells are unique in terms of the variety of their potential applications; they can provide power for systems as large as a utility power station and as small as a laptop computer. Fuel cells can be used in a wide range of applications, including transportation, material handling, stationary, portable, and emergency backup power applications. Fuel cells have several benefits over conventional combustion-based technologies currently used in many power plants and passenger vehicles. Fuel cells can operate at higher efficiencies than combustion engines and can convert the chemical energy in the fuel to electrical energy with efficiencies of up to 60%. Fuel cells have lower emissions than combustion engines. Hydrogen fuel cells emit only water, so there are no carbon dioxide emissions and no air pollutants that create smog and cause health problems at the point of operation. Also, fuel cells are quiet during operation as they have fewer moving parts. This work is a representation of Ansys capabilities to simulate fuel cell for academic learning .
Nucleate Boiling is a topic of interest for various industrial
applications, such as heat exchangers, fluid management in
micro-gravity for space applications or spray cooling. Whereas
some macroscopic models or semi-empirical correlations can provide realistic results in different configurations, the capabilities of such models are often limited by a lack of understanding about the microscopic details involved in the whole process. The case study gives a sample process of using ansys fluent to a reasonable level for investigating the phenomenon of departure from nucleate boiling in heat exchanger .
CFD comes handy in the investigations of heat transfer problems related to everyday usage . Placement of air-conditioned in large spaces is one such area where the use of computational fluid dynamics is envisaged in this case study .
In fluid dynamics, slosh refers to the movement of liquid inside another object (which is, typically, also undergoing motion).
Strictly speaking, the liquid must have a free surface to constitute a slosh dynamics problem, where the dynamics of the liquid can interact with the container to alter the system dynamics significantly. Liquid sloshing strongly influences the directional dynamics and safety performance of highway tank vehicles in a highly adverse manner. Hydrodynamic forces and moments arising from liquid cargo oscillations in the tank under steering and/or braking maneuvers reduce the stability limit and controllability of partially-filled tank vehicles. Anti-slosh devices such as baffles are widely used in order to limit the adverse liquid slosh effect on directional performance and stability of the tank vehicles.
The Objective of the study is to perform a CFD analysis of a Centrifugal Pump. The geometry for the analysis contains two different parts i.e. volute casing and impeller. The necessity of the work is to follow the recommended procedure for the analysis using turbomachinery module CFX under ANSYS Workbench.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
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Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
2. Objective Of The Case
Study
A shell & Tube heat exchanger is to be
designed which has the capacity to
raise the temperature of fresh water
from 40°C to 50°C at a flow rate of
15LPM. The other fluid available is
waste water at temperature 80°C and
flow rate of 50LPM.
First of all, an analytical calculation
was performed to estimate the size of
heat exchanger required.
(Determination Of Heat Transfer Area)
CFD simulation was performed later in
ANSYS Fluent to validate the
calculations.
3. Determination Of Heat Transfer Area Required
To determine the heat transfer area, following steps were followed as described below:
Temperature of the hot fluid at the outlet after heat exchange process using the equation:
𝑇ℎ,𝑜𝑢𝑡 = 𝑇ℎ,𝑖𝑛 −
𝑄
𝑚ℎ×𝐶𝑝,ℎ
, where 𝑄 = 𝑚𝑐 × 𝐶𝑝,𝑐 × 𝑇𝑐,𝑜𝑢𝑡 − 𝑇𝑐,𝑖𝑛
Q= 10460 Watts & Th,out =77°C
The bulk mean temperature of tube and
shell side can be then calculated using
the equation:
𝑇𝑏 =
𝑇𝑖𝑛 + 𝑇𝑜𝑢𝑡
2
𝑇𝑏,tube = 45°C & 𝑇𝑏,shell = 78.5°C
Fluid properties at bulk temperature are
then used for calculation of Reynolds
and Prandtl number.
4. Determination Of Heat Transfer Area Required
Tube of inner diameter 0.05m and outer diameter 0.054m inside another concentric tube of inner diameter 0.1m was assumed first
to determine the heat transfer area required for this heat transfer purpose.
Reynolds & Prandtl number calculation was performed for both sides. (With properties at bulk temperature)
Then Nusselt number was predicted using Dittus-Boelter correlation.
𝑅𝑒𝑡𝑢𝑏𝑒 =
𝜌@𝑏𝑢𝑙𝑘 𝑡𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒 × 𝐷ℎ,𝑡𝑢𝑏𝑒 × 𝑣𝑖𝑛,𝑡𝑢𝑏𝑒
𝜇@𝑏𝑢𝑙𝑘 𝑡𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒
𝑃𝑟𝑡𝑢𝑏𝑒 =
𝜇@𝑏𝑢𝑙𝑘 𝑡𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒 × 𝐶𝑝
𝑘
= 8847 = 5.0
𝑅𝑒𝑠ℎ𝑒𝑙𝑙 =
𝜌@𝑏𝑢𝑙𝑘 𝑡𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒 × 𝐷ℎ,𝑡𝑢𝑏𝑒 × 𝑣𝑖𝑛,𝑠ℎ𝑒𝑙𝑙
𝜇@𝑏𝑢𝑙𝑘 𝑡𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒
= 15682 𝑃𝑟𝑠ℎ𝑒𝑙𝑙 =
𝜇@𝑏𝑢𝑙𝑘 𝑡𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒 × 𝐶𝑝
𝑘
= 3.1
𝑁𝑢 = 0.023 × 𝑅𝑒0.8 × 𝑃𝑟0.4
Dittus-Boelter correlation is given as:
𝑁𝑢𝑡𝑢𝑏𝑒 = 63
𝑁𝑢𝑠ℎ𝑒𝑙𝑙 = 82
ℎ =
𝑁𝑢 𝑋 𝑘
𝐷ℎ
Heat transfer coefficients are then calculated as:
ℎ𝑡𝑢𝑏𝑒 𝑜𝑟 ℎ𝑖 = 756 ℎ𝑠ℎ𝑒𝑙𝑙 𝑜𝑟 ℎ𝑜 = 1071.5
Once the heat transfer coefficients at the inner side
and outer side of the tube are calculated then the
overall heat transfer coefficient can be estimated
next.
5. The overall heat transfer coefficient is estimated using the equation as shown below:
1
𝑈𝑜
=
1
ℎ𝑜
+
1
𝑘
𝑟𝑜
1
ln
𝑟𝑜
𝑟𝑖
+
1
𝑟𝑖
𝑟𝑜
ℎ𝑖
Determination Of Heat Transfer Area Required
𝑈𝑜 was calculated as 434W/m2-k
LMTD was calculated next.
𝐿𝑀𝑇𝐷 =
𝑇1 − 𝑇2
ln
𝑇1
𝑇2
Where, 𝑇1 = 𝑇ℎ,𝑜𝑢𝑡 − 𝑇𝑐,𝑖𝑛𝑙𝑒𝑡 and 𝑇2 = 𝑇ℎ,𝑖𝑛𝑙𝑒𝑡 − 𝑇𝑐,𝑜𝑢𝑡
𝑇1 = 77 − 40 = 37°𝐶
𝑇2 = 80 − 50 = 30°𝐶
Thus LMTD = 33.33°C
Required heat transfer area is then calculated using the equation.
𝑄 = 𝑈𝑜 × 𝐴𝑜 × 𝐿𝑀𝑇𝐷
𝐴𝑜= 0.7m2 (Approximately)
L=4.32m of diameter assumed.
6. If a single tube of diameter 0.054m (outer) and 0.05m (inner) is used, then the length of tube required will be 4.32m.
Instead of using a single tube, we will use multiple tubes of smaller diameter.
Let us assume the tube diameter be 0.03 (outer) & 0.025m (inner). (Length of tube = 1.0m)
Then the number of tubes required will be 7 to get the same heat transfer area.
Designing A Shell & Tube Heat Exchanger
Instead of using single tube of 4.32m, a shell
tube heat exchanger design was selected as
shown.
7. Drawing Of Heat Exchanger
Some important dimensions are shown here.
8. Solidworks model of shell & tube heat exchanger was imported in ANSYS DM, and then the fluid volume was extracted.
Due to symmetry in the CFD model, symmetry assumption was taken and the computational time was reduced to half.
The model was then meshed in the ANSYS mesh software. Inflation layer was applied at the walls to capture the
boundary layer.
CFD model & Mesh
CFD MODEL AFTER
TAKING SYMMETRY
MESHED MODEL
9. The figure below shows the temperature contour in the XY plane or the plane of symmetry. It can be seen that the
temperature of tube fluid (i.e. cold water) has increased from 40°C to 50°C as required. This indicates the validity of
the calculations done above. On the other hand, the shell fluid shows temperature drop from 80°C to 77°C after
exchanging the heat with tube fluid.
CFD Results – Temperature Contour On XY Plane
10. The results can also be seen in the
top view on ZX plane. The
temperature drop of 10°C can be
seen in the tube fluid.
The heat exchange between the two
fluids along the heat exchanger
length can be seen clearly in the
figure below
CFD Results TEMPERATURE
CONTOUR ON ZX PLANE
TEMPERATURE CONTOURS
ON YZ PLANE
11. Conclusion
In this case study, a shell and tube heat
exchanger was designed using analytical
calculations and then simulated using ANSYS
CFD.
As theoretically calculated, the tube fluid
temperature shows temperature rise of 10°C
where as the shell fluid shows temperature
drop of 3°C.
The overall heat transfer coefficient
calculated using CFD was 422 W/m2-K
against the theoretical calculation of 434
W/m2-K with a percentage error of 2.8%.