The reactivity coefficient is a very important parameter for safety and Stability of reactors operation. To provide
the safety analysis of the reactor, the calculation of changes in reactivity caused by temperature is necessary
because it is related to the reactor operation. The objective is to study the effect of the temperature reactivity
coefficients of fuel and moderator of the PWR core, as well as the moderator density and boron concentration on
fluid density, reactivity, void fraction. peak fuel clad temperature and time to core uncover were found for two
feedback cases. This paper focuses on the effect of the Reactivity feedback, of the 6" (6-inch) Cold Leg
SBLOCA sequences in a 4-loop PWR Westinghouse nuclear power plant with a scram for various feedback,
moderator density coefficient, MDC, moderator temperature coefficient, MTC, the fuel temperature coefficient,
FTC, and boron concentrations. Dragon neutronic code is used for calculating reactivity's coefficient which is
used in RELAP5 thermal hydraulic computer code to simulate the effect of Reactivity feedback during Cold
Leg SBLOCA. The plant nodalization consists of two loops; the first one represents the broken loop and the
second one represents the other three intact loops. In the present analysis two models in RELAP5 code for
computation of the reactivity feedback, separable and tabular models are used. The 6-inch break size was chosen
because the previous work [1], showed that it was the worst size break in a 4-loop PWR Westinghouse. The
results show that the neglecting of the reactivity feed-back effect causes overheating of the clad and that the
importance of the reactivity feed-back on calculating the power (reactivity) which the key parameter that
controls the clad and fuel temperatures to maintain them below their melting point and therefore prevent core
uncover and fuel damage where the fuel temperature, clad temperature and core water level are in the range.
Process Design for Natural Gas TransmissionVijay Sarathy
Compressor stations form a keyl part of the natural gas pipeline network that moves natural gas from individual producing well sites to end users. As natural gas moves through a pipeline, distance, friction, and elevation differences slow the movement of the gas, and reduce pressure. Compressor stations are placed strategically within the gathering and transportation pipeline network to help maintain the pressure and flow of gas to market. The following is a tutorial to perform process design of a natural gas transmission system.
Predicting Performance Curves of Centrifugal Pumps in the Absence of OEM DataVijay Sarathy
Chemical and Mechanical Engineers in the oil & gas industry often carry out the task of conducting technical studies to evaluate piping and pipeline systems during events such as pump trips and block valve failures that can lead to pipes cracking at the welded joints, pump impellers rotating in the reverse direction and damaged pipe supports due to excessive vibrations to name a few. Although much literature is available to mitigate such disturbances, a key set of data to conduct transient studies are pump performance curves, a plot between pump head and flow.
The present paper is aimed at applying engineering research in industrial applications for practicing engineers. It provides a methodology called from available literature from past researchers, allowing engineers to predict performance curves for a Volute Casing End Suction Single Stage Radial Pump. In the current undertaking, the pump in question is not specific to any one industry but the principles are the same for a Volute Casing End suction radial pump.
Gas Condensate Separation Stages – Design & OptimizationVijay Sarathy
The life cycle of an oil & gas venture begins at the wellhead where subsurface engineers work their way through surveying, drilling, laying production tubing and well completions. Once a well is completed, gathering lines from each well is laid to gather hydrocarbons and transported via a main trunk line to a gas oil separation unit (GOSP) to be processed further to enhance their product value for sales. Gas condensate wells consist of natural gas which is rich in heavier hydrocarbons that are recovered as liquids in separators in field facilities or gas-oil separation plants (GOSP).
The following tutorial is aimed at demonstrating how to optimize and provide the required number of separation stages to process a gas condensate mixture and separate them into their respective vapour phase and liquid phase – termed as “Stage Separation”. Stage separation consists of laying a series of separators which operate at consecutive lower pressures to strip out vapours from the well liquids & resulting in a stabilized liquid. Prior to any hydrocarbon processing in a gas processing plant or a refinery, it is imperative to maximize the liquid recovery as well as provide a stabilized liquid hydrocarbon.
Flash Steam and Steam Condensates in Return LinesVijay Sarathy
In power plants, boiler feed water is subjected to heat thereby producing steam which acts as a motive force for a steam turbine. The steam upon doing work loses energy to form condensate and is recycled/returned back to reduce the required make up boiler feed water (BFW).
Recycling steam condensate poses its own challenges. Flash Steam is defined as steam generated from steam condensate due to a drop in pressure. When high pressure and temperature condensate passes through process elements such as steam traps or pressure reducing valves to lose pressure, the condensate flashes to form steam. Greater the drop in pressure, greater is the flash steam generated. This results in a two phase flow in the condensate return lines.
Variable Speed Drives for Gas compressor OperationsVijay Sarathy
To understand the effects of Variable Speed Drive (VSD) and Fixed Speed Drive (FSD) mode of operation on gas compressor start-up, a case study is made.
Gas Compression Stages – Process Design & OptimizationVijay Sarathy
The following tutorial demonstrates how to estimate the required number of compression stages and optimize the individual pressure ratio in a multistage centrifugal compression system.
Predicting Performance Curves of Centrifugal Pumps in the Absence of OEM DataVijay Sarathy
Chemical and Mechanical Engineers in the oil & gas industry often carry out the task of conducting technical studies to evaluate piping and pipeline systems during events such as pump trips and block valve failures that can lead to pipes cracking at the welded joints, pump impellers rotating in the reverse direction and damaged pipe supports due to excessive vibrations to name a few. Although much literature is available to mitigate such disturbances, a key set of data to conduct transient studies are pump performance curves, a plot between pump head and flow.
The present paper is aimed at applying engineering research in industrial applications for practicing engineers. It provides a methodology called from available literature from past researchers, allowing engineers to predict performance curves for a Volute Casing End Suction Single Stage Radial Pump. In the current undertaking, the pump in question is not specific to any one industry but the principles are the same for a Volute Casing End suction radial pump.
In this topic we have discussed working principle of a Batch Reactor. We've also discussed its kinetics like its Rate equation, Material and Energy balance. Its Design steps also have been discussed.
Process Design for Natural Gas TransmissionVijay Sarathy
Compressor stations form a keyl part of the natural gas pipeline network that moves natural gas from individual producing well sites to end users. As natural gas moves through a pipeline, distance, friction, and elevation differences slow the movement of the gas, and reduce pressure. Compressor stations are placed strategically within the gathering and transportation pipeline network to help maintain the pressure and flow of gas to market. The following is a tutorial to perform process design of a natural gas transmission system.
Predicting Performance Curves of Centrifugal Pumps in the Absence of OEM DataVijay Sarathy
Chemical and Mechanical Engineers in the oil & gas industry often carry out the task of conducting technical studies to evaluate piping and pipeline systems during events such as pump trips and block valve failures that can lead to pipes cracking at the welded joints, pump impellers rotating in the reverse direction and damaged pipe supports due to excessive vibrations to name a few. Although much literature is available to mitigate such disturbances, a key set of data to conduct transient studies are pump performance curves, a plot between pump head and flow.
The present paper is aimed at applying engineering research in industrial applications for practicing engineers. It provides a methodology called from available literature from past researchers, allowing engineers to predict performance curves for a Volute Casing End Suction Single Stage Radial Pump. In the current undertaking, the pump in question is not specific to any one industry but the principles are the same for a Volute Casing End suction radial pump.
Gas Condensate Separation Stages – Design & OptimizationVijay Sarathy
The life cycle of an oil & gas venture begins at the wellhead where subsurface engineers work their way through surveying, drilling, laying production tubing and well completions. Once a well is completed, gathering lines from each well is laid to gather hydrocarbons and transported via a main trunk line to a gas oil separation unit (GOSP) to be processed further to enhance their product value for sales. Gas condensate wells consist of natural gas which is rich in heavier hydrocarbons that are recovered as liquids in separators in field facilities or gas-oil separation plants (GOSP).
The following tutorial is aimed at demonstrating how to optimize and provide the required number of separation stages to process a gas condensate mixture and separate them into their respective vapour phase and liquid phase – termed as “Stage Separation”. Stage separation consists of laying a series of separators which operate at consecutive lower pressures to strip out vapours from the well liquids & resulting in a stabilized liquid. Prior to any hydrocarbon processing in a gas processing plant or a refinery, it is imperative to maximize the liquid recovery as well as provide a stabilized liquid hydrocarbon.
Flash Steam and Steam Condensates in Return LinesVijay Sarathy
In power plants, boiler feed water is subjected to heat thereby producing steam which acts as a motive force for a steam turbine. The steam upon doing work loses energy to form condensate and is recycled/returned back to reduce the required make up boiler feed water (BFW).
Recycling steam condensate poses its own challenges. Flash Steam is defined as steam generated from steam condensate due to a drop in pressure. When high pressure and temperature condensate passes through process elements such as steam traps or pressure reducing valves to lose pressure, the condensate flashes to form steam. Greater the drop in pressure, greater is the flash steam generated. This results in a two phase flow in the condensate return lines.
Variable Speed Drives for Gas compressor OperationsVijay Sarathy
To understand the effects of Variable Speed Drive (VSD) and Fixed Speed Drive (FSD) mode of operation on gas compressor start-up, a case study is made.
Gas Compression Stages – Process Design & OptimizationVijay Sarathy
The following tutorial demonstrates how to estimate the required number of compression stages and optimize the individual pressure ratio in a multistage centrifugal compression system.
Predicting Performance Curves of Centrifugal Pumps in the Absence of OEM DataVijay Sarathy
Chemical and Mechanical Engineers in the oil & gas industry often carry out the task of conducting technical studies to evaluate piping and pipeline systems during events such as pump trips and block valve failures that can lead to pipes cracking at the welded joints, pump impellers rotating in the reverse direction and damaged pipe supports due to excessive vibrations to name a few. Although much literature is available to mitigate such disturbances, a key set of data to conduct transient studies are pump performance curves, a plot between pump head and flow.
The present paper is aimed at applying engineering research in industrial applications for practicing engineers. It provides a methodology called from available literature from past researchers, allowing engineers to predict performance curves for a Volute Casing End Suction Single Stage Radial Pump. In the current undertaking, the pump in question is not specific to any one industry but the principles are the same for a Volute Casing End suction radial pump.
In this topic we have discussed working principle of a Batch Reactor. We've also discussed its kinetics like its Rate equation, Material and Energy balance. Its Design steps also have been discussed.
OPERATING ENVELOPES FOR CENTRIFUGAL PUMPSVijay Sarathy
The following tutorial provides a step by step procedure to predict the allowable operating range or “Operating Envelope” for a centrifugal pump’s range of operation.
This presentation gives a general idea on simulation in Aspen HYSYS software. It gives an knowledge on the selection of simulator and the selection of equation of states in simulators. It also gives a brief idea on the thermodynamics behind the simulators
CENTRIFUGAL COMPRESSOR SETTLE OUT CONDITIONS TUTORIALVijay Sarathy
Centrifugal Compressors are a preferred choice in gas transportation industry, mainly due to their ability to cater to varying loads. In the event of a compressor shutdown as a planned event, i.e., normal shutdown (NSD), the anti-surge valve is opened to recycle gas from the discharge back to the suction (thereby moving the operating point away from the surge line) and the compressor is tripped via the driver (electric motor or Gas turbine / Steam Turbine). In the case of an unplanned event, i.e., emergency shutdown such as power failure, the compressor trips first followed by the anti-surge valve opening. In doing so, the gas content in the suction side & discharge side mix.
Therefore, settle out conditions is explained as the equilibrium pressure and temperature reached in the compressor piping and equipment volume following a compressor shutdown
This is the powerpoint file of the reactor design that was assigned to me during my final year design project. I solved the rate equations in MATLAB to calculate the reactor volume.
Affinity Laws for Variable Speed Centrifugal PumpsVijay Sarathy
In retrofit jobs, depending on the application & plant revamps, fixed speed pumps are retrofitted with a variable frequency drive (VFD) to enable them to be operated at a different set of operating conditions. In Brownfield projects, design engineers would sometimes face situations where the manufacturer's datasheets indicate performance curves only for rated speeds & it becomes necessary to evaluate what are the other operating ranges the same pump can be used for after retrofitting.
In the following short article, I've put up some points covering
1. Advantages of Variable Frequency Drives
2. When VFD’s Are Not Advantageous
3. Selection Process - New Pumps & Retrofit Pumps
4. Example Case Study to generate Performance Curves for VSD Retrofit (Single Stage End Suction Centrifugal Pump)
Engineers often use softwares to perform gas compressor calculations to estimate compressor duty, temperatures, adiabatic & polytropic efficiencies, driver & cooler duty. In the following exercise, gas compressor calculations for a pipeline composition are shown as an example case study.
Excel sheet Download Link: https://www.scribd.com/document/385945712/PSV-Sizing-Tool-API-Based-Calc-Sheets
PSV Sizing for Blocked Liquid Discharge Condition
PSV Sizing for Blocked Gas Discharge Condition
PSV Sizing for Fire Case of Liquid Filled Vessel
PSV Sizing for Control Valve Fail Open Case
Relief Valve Sizing for Thermal Expansion
Restriction Orifice Sizing for Gas Flow
Restriction Orifice Sizing for Liquid Flow
Single Phase Flow Line Sizing Tool
Gas Control Valve Sizing Tool
OPTIMIZATION OF AN ORGANIC RANKINE CYCLE IN ENERGY RECOVERY FROM EXHAUST GASE...IAEME Publication
This paper describes thermal analysis and optimization of an organic Rankine cycle (ORC) integrated with a power generating stationary diesel engine. A simple ORC, with a regenerator, is considered here as a bottoming cycle for producing additional power by recovering waste energy
from the exhaust gases of the engine. Taking evaporation pressure and condensation temperature as two decision variables, a genetic algorithm is used for simultaneously maximizing three objective functions - exergy efficiency, thermal efficiency, and specific network.
OPERATING ENVELOPES FOR CENTRIFUGAL PUMPSVijay Sarathy
The following tutorial provides a step by step procedure to predict the allowable operating range or “Operating Envelope” for a centrifugal pump’s range of operation.
This presentation gives a general idea on simulation in Aspen HYSYS software. It gives an knowledge on the selection of simulator and the selection of equation of states in simulators. It also gives a brief idea on the thermodynamics behind the simulators
CENTRIFUGAL COMPRESSOR SETTLE OUT CONDITIONS TUTORIALVijay Sarathy
Centrifugal Compressors are a preferred choice in gas transportation industry, mainly due to their ability to cater to varying loads. In the event of a compressor shutdown as a planned event, i.e., normal shutdown (NSD), the anti-surge valve is opened to recycle gas from the discharge back to the suction (thereby moving the operating point away from the surge line) and the compressor is tripped via the driver (electric motor or Gas turbine / Steam Turbine). In the case of an unplanned event, i.e., emergency shutdown such as power failure, the compressor trips first followed by the anti-surge valve opening. In doing so, the gas content in the suction side & discharge side mix.
Therefore, settle out conditions is explained as the equilibrium pressure and temperature reached in the compressor piping and equipment volume following a compressor shutdown
This is the powerpoint file of the reactor design that was assigned to me during my final year design project. I solved the rate equations in MATLAB to calculate the reactor volume.
Affinity Laws for Variable Speed Centrifugal PumpsVijay Sarathy
In retrofit jobs, depending on the application & plant revamps, fixed speed pumps are retrofitted with a variable frequency drive (VFD) to enable them to be operated at a different set of operating conditions. In Brownfield projects, design engineers would sometimes face situations where the manufacturer's datasheets indicate performance curves only for rated speeds & it becomes necessary to evaluate what are the other operating ranges the same pump can be used for after retrofitting.
In the following short article, I've put up some points covering
1. Advantages of Variable Frequency Drives
2. When VFD’s Are Not Advantageous
3. Selection Process - New Pumps & Retrofit Pumps
4. Example Case Study to generate Performance Curves for VSD Retrofit (Single Stage End Suction Centrifugal Pump)
Engineers often use softwares to perform gas compressor calculations to estimate compressor duty, temperatures, adiabatic & polytropic efficiencies, driver & cooler duty. In the following exercise, gas compressor calculations for a pipeline composition are shown as an example case study.
Excel sheet Download Link: https://www.scribd.com/document/385945712/PSV-Sizing-Tool-API-Based-Calc-Sheets
PSV Sizing for Blocked Liquid Discharge Condition
PSV Sizing for Blocked Gas Discharge Condition
PSV Sizing for Fire Case of Liquid Filled Vessel
PSV Sizing for Control Valve Fail Open Case
Relief Valve Sizing for Thermal Expansion
Restriction Orifice Sizing for Gas Flow
Restriction Orifice Sizing for Liquid Flow
Single Phase Flow Line Sizing Tool
Gas Control Valve Sizing Tool
OPTIMIZATION OF AN ORGANIC RANKINE CYCLE IN ENERGY RECOVERY FROM EXHAUST GASE...IAEME Publication
This paper describes thermal analysis and optimization of an organic Rankine cycle (ORC) integrated with a power generating stationary diesel engine. A simple ORC, with a regenerator, is considered here as a bottoming cycle for producing additional power by recovering waste energy
from the exhaust gases of the engine. Taking evaporation pressure and condensation temperature as two decision variables, a genetic algorithm is used for simultaneously maximizing three objective functions - exergy efficiency, thermal efficiency, and specific network.
INTRODUCTION
COMPARISION BETWEEN FIXED BED VS FLUIDISED BED REACTOR
SELECTION CRITERIA FOR CATALYST REACTOR
DESIGN OF CATALYST REACTOR
DESIGN OF DEACTIVATION OF CATALYST
Experimental investigate to obtain the effectiveness of regenerator using Air.IJESFT
The regenerator is a kind of heat exchanger that provides a way to get the gas to the low temperature with as much potential work (cooling power) as possible without carrying a lot of heat with it. It doesn’t put heat in or out of the system but it absorbs heat from the gas on one part of the pressure cycle and returns heat to the gas on the other part.
More recent applications of regenerators in cryogenic systems can be found in small cryogenic refrigerators (cryocoolers). Systems such as the Stirling Gifford-McMahon, pulse tube, Solvay, Vuilleumier and magnetic cycle refrigerators all use either a static or rotary regenerator. In fact, the success these coolers have achieved is directly related to the characteristics of compact size and efficiency of the regenerator.
Regenerator effectiveness of 99% results in 21% loss of refrigeration effect, similarly regenerator effectiveness of 98% results in 42% loss of refrigeration effect, with refrigeration effectiveness of 95.238% the loss of refrigeration is 100%. i.e. no net cooling is produced.
In cryogenic applications the regenerator is typically made up of 100 to 500 meshes SS 304, Phosphorous bronze screens or small lead spheres (150 to 300 micro meters) are used, that are tightly packed together and held in place on either end in the same manner.
To develop experimental setup at our laboratory level by using air as working fluid and find out the effectiveness of various regenerative materials is basic goal of this work.
Steam Condenser Exergy Analysis of Steam Power Plant at Different LoadsNAAR Journal
This paper presents steam condenser exergy analysis of 50 MW unit of the power plant by varying the ambient temperature from 5 C to 42 C at different loads. The performance parameters and the dependent variables are the exergy entering in the condenser, exergy out from the condenser, exergy efficiency of the plant, exergy destruction in the condenser and the exergy efficiency of condenser. Whereas the independent variables are ambient temperature and condenser pressure. It was seen that increases of exergy efficiency of the plant depends on combined effect of ambient temperature and condenser pressure as the sole variation of ambient temperature doesn’t have much effect on the performance parameters. The varying of ambient temperature without altering the condenser pressure doesn’t have any significant impact but by varying simultaneously the ambient temperature along with the changing of condenser pressure has profound effect on the performance parameters. As the Condenser pressure increases the heat loss is also increasing which shows the major portion of energy loss occurs in condenser. In comparison of heat loss in condenser the exergy destruction in condenser is very less. At the optimal condenser pressure 0.00804 MPa the exergy efficiency of the whole unit, exergy destruction in condenser, exergy efficiency of condenser, Heat loss (Q) in condenser and Wtotal are as 26.26%, 198.1KW, 99.72%, 81190 KW and 53.4 MW respectively and the optimal condition is attained at the full load(100%) or designed operating parameters.
Distribution, Habitat Utilization and Threats to Chinese Pangolin (Manis Pent...NAAR Journal
The Chinese Pangolin (Manis pentadactyla) is a unique mammal
having stiff scales, body shape slender like a reptile, burrow living and
highly nocturnal. It is receiving less scientific attention therefore
information on its ecology, behavior, status and distribution is still
scarce in Nepal. Pangolins are distributed in many districts and
protected areas of Nepal but are threatened due to habitat destruction,
illegal trade and lack of awareness. Thus, this research was conducted
to assess the distribution, habitat utilization and threats to Chinese
Pangolin in Mahabharat and Chure community forests of Sindhuli
district. The primary data were collected by using the methods adopted
in National Pangolin Survey, Nepal (2016). The sample size for
scheduled questionnaire survey was calculated by using the formula
given by Krejice and Morgan in 1970. The secondary data were
collected from the DFO, Sector forest office and community forest
office. Through field survey within the transect of 500 meters;
distribution of burrows, their geographical coordinates, slope,
elevation, canopy cover, soil moisture, soil colour and texture,
distance to settlement, water and road and number of ants/termites
mound were recorded. A total of 348 burrows were recorded including
206 (91 active, 115 inactive) in Mahabharat Community Forest and
142 (57 active, 85 inactive) in Chure Community Forest. The
elevation range of species was from 1400 m to 1700 m with maximum
number of burrows at slope range of 30⁰-40⁰ in Mahabharat
community forest. However, in Chure community forest, the elevation
range of species was from 900 m to 1300 m with maximum number of
burrows at slope range of 20⁰-30⁰. The highest frequency of burrows
was recorded in brown and light yellow colour soil in Mahabharat and
Chure community forest respectively. Mostly the burrows were
recorded in Schima wallichii and Shorea robusta dominant forests in Mahabharat and Chure community forest respectively. Poaching for
meat and traditional medicine and habitat destruction were major
threats to pangolin at the sites and their conservation status was found
to be worse.
PERFORMANCE ANALYSIS OF A COMBINED CYCLE GAS TURBINE UNDER VARYING OPERATING ...meijjournal
The combined cycle gas turbine integrates the Brayton cycle as topping cycle and the steam turbine
Rankine cycle as bottoming cycle in order to achieve higher thermal efficiency and proper utilization of
energy by minimizing the energy loss to a minimum. In this work, the effect of various operating
parameters such as maximum temperature and pressure of Rankine cycle, turbine inlet temperature and
pressure ratio of Brayton cycle on the net output work and thermal efficiency of the combine cycle are
investigated. The outcome of this work can be utilized in order to facilitate the design of a combined cycle
with higher efficiency and output work. A MATLAB simulation has been carried out to study the effects and
influences of the above mentioned parameters on the efficiency and work output.
Investigating The Performance of A Steam Power PlantIJMERJOURNAL
ABSTRACT: The performance analysis of Shobra El-Khima power plant in Cairo, Egypt is presented based on energy and exergy analysis to determine the causes , the sites with high exergy destruction , losses and the possibilities of improving the plant performance. The performance of the plant was evaluated at different loads (Full, 75% and, 50 %). The calculated thermal efficiency based on the heat added to the steam was found to be 41.9 %, 41.7 %, 43.9% , while the exergetic efficiency of the power cycle was found to be 44.8%, 45.5% and 48.8% at max, 75% and, 50 % load respectively. The condenser was found to have the largest energy losses where (54.3%, 55.1% and 56.3% at max, 75% and, 50 % load respectively) of the added energy to the steam is lost to the environment. The maximum exergy destruction was found to be in the turbine where the percentage of the exergy destruction was found to be (42%, 59% and 46.1% at max, 75% and, 50 % load respectively). The pump was found to have the minimum exergy destruction. It was also found that the exergy destruction in feed water heaters and in the condenser together represents the maximum exergy destruction in the plant (about 52%). This means that the irreversibilities in the heat transfer devices in the plant have a significant role on the exergy destruction. So, it is thought that the improvement in the power plant will be limited due to the heat transfer devices.
Improving and Comparing the Coefficient of Performance of Domestic Refgirator...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Similar to Reactivity Feedback Effect on the Reactor Behaviour during SBLOCA in a 4-loop PWR Westinghouse Design (20)
Anti-Smog Radar Application for VehiclesIJMREMJournal
Smog is regarded as a dangerous situation for vehicles as the visibility of human fails and a person cannot
drive smoothly and safely which can lead to severe accidents and routine disturbances. Hence, “Anti-Smog
Radar Application for Vehicles” is proposed using Internet of Things technology which ensures the smooth flow
of vehicles in smog and prevents accidents in time and cost-efficient manner by detecting and displaying the
front objects with their important information (distance, position, velocity and size) on smart phone used by
authenticated drivers. The radar application controls the hardware system to be deployed on vehicles through
which the user can start, stop and set the hardware in particular direction. The hardware contains NodeMcu
(Microcontroller with built-in Wi-Fi), Ultrasonic sensor and servo motor. The servo is used to detect the
position of front objects and ultrasonic sensor is clipped on servo to detect the objects. For alerts, the objects
are drawn with different colors on application i.e. the red colored objects will be near to the vehicle, the yellow
colored objects will be at some distance from the vehicle and the green colored objects will be far from the
vehicle. Kalman algorithm is used to filter the ultrasonic readings to eliminate the noise. The proposed system
can work in every condition i.e. in day and night.
IoT based Environmental Monitoring and Control SystemIJMREMJournal
IoT plays a major role in collecting the information from the sensing unit enclosing our environment due to
alterations in the climate which led to the significance of environmental monitoring. This Paper presents a
development of real time environmental monitoring and control system by utilizing Node MCU, DHT11 sensor,
ACS712 current sensor, Thing Speak (Open IoT analytics service) and Blynk application. The main task of
monitoring parameters (Humidity, temperature and power consumption) with real time sensors is done by Thing
Speak continuously which has API (Application programming Interface) for gathering sensed data and enabling
users to observe the monitored data in graphs for an interval of every 15 seconds.
This project is also designed to control home devices sitting at any place in the world by utilizing power
efficiently through Blynk application which is used to read data from sensors located in home environment using
smart phone and to turn on/off heating and cooling appliances automatically with respect to room temperature
values.
Analysis and Implementation of Solid-State Relays in Industrial application F...IJMREMJournal
There are many applications and circumstances where switching devices are required for proper operation,
controlling and isolating the high power and low power systems. The most widely used switching devices are
electromechanical relays and solid state relays. In this work, analysis and implementation of solid state relays over
electromechanical relays with respect to instantaneous current supply inindustrial application is conducted and
compared. For this purpose, an experimental setup is arranged for switching operation of electromechanical relays
and solid-state relays.The results of voltage and the current transients are analyzed and compared. It was observed
that there are no transients occurred during switching of solid state relays where as during switching of
electromechanical relay transients observed in volatge and current waveforms. So, it is advisable to use the solid
state relays over electromagnetic relay for safe and smooth operation of the system.
MIM (Mobile Instant Messaging) Classification using Term Frequency-Inverse Do...IJMREMJournal
The focus of the study is based on binary sentiment classification on aspect level to develop a hybrid sentiment
classification framework of WhatsApp MIMs (Mobile Instant Messages). It has been carried out into two phases
i.e. training phase and testing phase. The training phase, 75% data is used for training dataset. Pre-processing
techniques like tokenization, removing stop words, case normalization, removing punctuation and stemming are
applied to acquire cleaner dataset to be used as input. The output is sent to the classifier after applying TF-IDF
for feature weighting. In the second phase, the classifier is trial with 25% testing dataset. Bernoulli’s Naïve
Bayesian classifier which is an improved form of traditional Naïve Bayesian classifier is used to classify
sentiments. There are 417 messages in total where 244 and 173 are classified as positive and negative
respectively. The proposed model has achieved satisfactory results up to 81.73% in comparison to base-line
classification model by getting 12 points higher accuracy i.e. 69.23%.
Is Lean Management applicable to the hospital and for which results?IJMREMJournal
lean management is a mode of organism inspired by Toyotism; His practice is evident throughout the world and
is one of the most affected institutions, except that the latter is a different profession. There is no shared vision
among the different actors on measuring the performance of the hospital. The activity of the hospital applies to
unique "products": each patient, with its peculiar specificity. The relationship of the workers with the patient is
radically different from the relationship of the worker with his product. That is why the practice of Lean has a
certain specificity in the health field.
Fabrication and Performance Analysis of Solar Tracking System by Using By-Pas...IJMREMJournal
Energy is a burning issue that almost every person experience now a days. Energy demand increases exponentially
since a decade. Due to the global warming and it’s threatening impacts on human life. Therefore, to overcome
such disastrous impacts on the planet, renewable energy resources play vital role now a days. Solar energy is one
of the vastest available renewable energy resources around the globe, but the main issue is its poor efficiency.
Pakistan is facing energy shortage that can be compensated through solar power and the need is to design a project
that maximizes its efficiency. So, the research is mainly focused on improving efficiency of solar panels against
shading loss by using different techniques. In this research, different results will be obtained and compared with
different techniques which are LDR based solar tracking system, by-pass diodes technology and super capacitors.
Fabrication of solar tracker is based on Microcontroller that drives L298N driver to operate stepper motor.
Lyapunov-type inequalities for a fractional q, -difference equation involvin...IJMREMJournal
In this paper, we present new Lyapunov-type inequalities for a fractional boundary value problem of
fractional
q, -difference equation with p-Laplacian operator. The obtained inequalities are used to obtain a
lower bound for the eigenvalues of corresponding equations.
The Policies of Government Intervention as Third-Party for Conflict in Bike-S...IJMREMJournal
This research accesses to the unbalance phenomenon between the rapid development of Sharing bicycle industry
and the good public order. Taking into account the inconsistent goals of bicycle companies and users, the local
government is employed as a third party to mediate the conflict. We establish the conflict model including three
decision makers - Enterprises, Citizens and Government - based on GMCR (Graph Model for Conflict Resolution)
theory, and then find out the equilibrium by means of the decision support system GMCR II. The results show that
the sustainable development of the Sharing bicycle market requires the cooperation and efforts of all the three
parties, the government plays a necessary role to guide the enterprises and the users. We also propose some
management insights on how to provide suggestions for the sharing bicycle companies to improve their
dispatching services, and how to establish and improve relevant laws and regulations to guide citizens to use
shared bicycles in order to achieve mutual benefits
Epidemiological study for Trichomonas Vaginalis for Discrete time model and C...IJMREMJournal
During the period of July until December 2017 Conduct an epidemiological study to investigate the prevalence
of Trichomonas Vaginalis among women who have been consulted for the consultation and emergency of the
maternity and child hospital in Diwaniyah city in Iraq. The number of specimens examined was 857 samples
and the ages ranged between 15-60 years. After the swabs were taken, the direct examination and coloring and
planting on the different food communities to diagnose parasitic Trichomonas vaginalis the incidence of
Trichomonas vaginalis was 129 (17%). Using the mathematical model discrete time model and continuous time
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and its elemental role, regulating consumers’ behaviours towards power savings can be a challenge. Remarkably,
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As anti-import sentiment and protectionism have been increasing, more papers have focused on using theories to explain or resolve them. However, most research has focused on disputes involving larger nations such that there is not much relatable information for disputes such as the one between South Africa and Zimbabwe. The aim of this paper was to bridge the knowledge gap by using the graph model for conflict resolution and the decision support software GMCRII to simulate possible responses to this regional trade conflict. This thirdparty intervention model will assist in investigating and prescribing a diplomatic solution with fair compromise to resolve the unequal trade problem between Zimbabwe and South Africa without harming the economies of both the countries. This research found that a peaceful resolution of the disagreement could be found by the addition of a third-party to help in the conflict resolution thereby ending the prolonged trade conflict. This undertaking will serve as a template for modelling and predicting an outcome in the event of third-party intervention for future trade disputes involving regional trade partners with emerging or developing economies such as those that exist in Africa
Proposed Framework for Effective Management of End-User Stakeholders’ in Publ...IJMREMJournal
Significant infrastructure such as roads, prisons, schools, rail tracks and train systems, among others are currently developed through the involvement of Public Private Partnership (PPP) arrangements which have been acknowledged internationally in recent time. The poor management of end-user stakeholder during PPP projects in developing nation like Nigeria has been established as one of the major factor affecting the successful growth and development of PPP projects. Due to the paucity in research on end-user stakeholder management on PPP projects in Nigeria, informs this study aim to expose the main strategic factors that can accommodate end-user stakeholder’s management in any PPP road project in Nigeria. The professionals that have worked on the project cum the end-user of the project area were used as targeted respondents for the adopted case study and survey strategies method approach. Thematic analysis was used to analyse the eighteen (18) interviews that were conducted having completed and analysed total number of 282 questionnaires using reliability and factor analysis approach. Seven valid underlying factors were revealed from 28 variables that were left on the questionnaire data with the aid of factor analysis which were used later as factors affecting end-user stakeholders’ management in PPP road project in Nigeria. A proposed framework was created with the seven underlying factors as a template for any successful PPP road project in developing country like Nigeria. These will quench the agitation of enduser stakeholders’ quarrels on PPP toll road projects
Fresh and Hardened Properties of Ground Granulated Blast Furnace Slag Made Co...IJMREMJournal
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Design and Evaluation of Open Graded Hot Mix Asphalt Using Cement as A Grout...IJMREMJournal
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Design of Cold Recycled Emulsified Asphalt Mixtures Using Portland Cement as ...IJMREMJournal
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Thermodynamic Analysis of Cooling Tower with Air to Air Heat Exchanger for Re...IJMREMJournal
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Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
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Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
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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.
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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/
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
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My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
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Reactivity Feedback Effect on the Reactor Behaviour during SBLOCA in a 4-loop PWR Westinghouse Design
1. ineering & Management (IJMREM)International Journal of Modern Research in Eng
||Volume|| 2||Issue|| 1||Pages|| 37-44 || January 2019|| ISSN: 2581-4540
www.ijmrem.com IJMREM Page 37
Reactivity Feedback Effect on the Reactor Behaviour during
SBLOCA in a 4-loop PWR Westinghouse Design
S. Helmy
Nuclear and Radiological Regulatory Authority (NRRA), Cairo, Egypt
------------------------------------------------------ABSTRACT----------------------------------------------------
The reactivity coefficient is a very important parameter for safety and Stability of reactors operation. To provide
the safety analysis of the reactor, the calculation of changes in reactivity caused by temperature is necessary
because it is related to the reactor operation. The objective is to study the effect of the temperature reactivity
coefficients of fuel and moderator of the PWR core, as well as the moderator density and boron concentration on
fluid density, reactivity, void fraction. peak fuel clad temperature and time to core uncover were found for two
feedback cases. This paper focuses on the effect of the Reactivity feedback, of the 6" (6-inch) Cold Leg
SBLOCA sequences in a 4-loop PWR Westinghouse nuclear power plant with a scram for various feedback,
moderator density coefficient, MDC, moderator temperature coefficient, MTC, the fuel temperature coefficient,
FTC, and boron concentrations. Dragon neutronic code is used for calculating reactivity's coefficient which is
used in RELAP5 thermal hydraulic computer code to simulate the effect of Reactivity feedback during Cold
Leg SBLOCA. The plant nodalization consists of two loops; the first one represents the broken loop and the
second one represents the other three intact loops. In the present analysis two models in RELAP5 code for
computation of the reactivity feedback, separable and tabular models are used. The 6-inch break size was chosen
because the previous work [1], showed that it was the worst size break in a 4-loop PWR Westinghouse. The
results show that the neglecting of the reactivity feed-back effect causes overheating of the clad and that the
importance of the reactivity feed-back on calculating the power (reactivity) which the key parameter that
controls the clad and fuel temperatures to maintain them below their melting point and therefore prevent core
uncover and fuel damage where the fuel temperature, clad temperature and core water level are in the range.
KEYWORDS: Reactivity feedback 6" Small-break loss-of-coolant accident Thermal hydraulic phenomena 4-
loop PWR Core uncovery.
---------------------------------------------------------------------------------------------------------------------------------------
Date of Submission: Date, 12 January 2019 Date of Accepted: 15. January 2019
---------------------------------------------------------------------------------------------------------------------------------------
I. INTRODUCTION
RELAP5 T.H system code has been developed for best-estimate transient simulation of light water reactor
coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant
system and the core for large and small loss-of-coolant accidents. RELAP5 code is the simplest model that can
be used to compute the power in a nuclear reactor. The power is computed using point kinetics approximation.
There are two options for the computation of the reactivity feedback. The first option is the separable point
reactor kinetics model and the other is tabular point reactor kinetics. In Separable Feedback Model The model
assumes feedback effects from moderator density and fuel, moderator temperatures. It is called the separable
model because each effect is assumed to be independent of the other effects. The tabular feedback model
computes reactivity from multi-dimensional table. The tabular model overcomes the objections of the
separable model since all feedback mechanisms can be nonlinear and interactions among the mechanisms are
included (e.g., the dependence of the moderator density feedback as function of the moderator fluid temperature
may be modeled). The four-dimensional table lookup and interpolation option (TABLE4A) computes reactivity
as a function of moderator densities, liquid moderator temperature, fuel temperature, and boron concentration.
In our work, TABLE4A is used [2]. Previous studies showed that, SBLOCA scenarios are depend on many
factors such as reactor design, break location, Safety injection set points, break size, boron concentration. Also,
the 6-inch break size was chosen because the previous works showed that it was the worst size break in a 4-loop
PWR Westinghouse [1&3] SBLOCA is characterized by five periods: blow-down, natural circulation, loop seal
clearance, boiloff, and core recovery, [4]. Kinetics parameters for the standard UO2 fuel and nitride fuel (UN-
U3Si2-UB4) have been developed from PARCS stand-alone full-core calculations to provide complete loss of
primary flow and small break (SB). Feedback coefficients included in the model are fuel temperature (Doppler),
coolant temperature, coolant density, and boron. Kinetics parameter inputs to the TRACE point-kinetics model
[5].
2. Reactivity Feedback Effect on the Reactor Behaviour…
www.ijmrem.com IJMREM Page 38
Water density and boron concentration were generated by the SRAC2006 code. The core calculations for
determination of the reactivity coefficient parameter are done by using NODAL3 code. The calculation results
showed that the fuel temperature, moderator temperature and boron reactivity coefficients. For the water density
reactivity coefficients, the positive reactivity occurs at the water temperature less than 190 o
C [6]. The AP1000
designed has a better inherent safety since it has the negative total feedback reactivity coefficients. The negative
reactivity coefficient ensures the reactor can stabilize the power when the reactor condition changes, such as fuel
and moderator temperature increase when the power goes to the nominal level [7-12]. The fuel temperature
coefficient (FTC) is reactivity change per fuel temperature change where the moderator temperature and density,
as well as boron concentration, are maintained at constant condition.
PLANT NODALIZATION: The plant nodalization is shown in Figure 1. The nodalization consists of two
loops; broken loop and intact loop. The intact loop simulates the three loops other than the loop containing the
pressurizer which represents the broken loop. The nodalization simulates all the main components of the reactor,
such as the reactor vessel internals, main coolant pumps, steam generators, pressurizer, feed water systems…etc.
For each loop, the ECCs is simulated as two-time dependent junctions (represent the charging system and the
safety injection system) and accumulator. The ECCs capacity for the intact loop is three folds that of the broken
loop. The charging system injects water at primary pressures less than the nominal pressure based on a low
pressurizer water level signal. The safety Injection system serves in the pressure range from 10.34 Mpa and up
to the atmospheric pressure. The accumulators cover the pressure range less than 4.136 Mpa. The core is
simulated as one average channel divided to seventeen radial volumes and also six axial volumes and connected
to the lower and upper plenums. Table 2 presents the main components and their equivalent code number in the
nodalization.
Figure (1) NPP Nodalization [1].
3. Reactivity Feedback Effect on the Reactor Behaviour…
www.ijmrem.com IJMREM Page 39
Table 2 Main Plant Components and the Corresponding Nodalization Numbers
Component Equivalent Code
Hot Leg 100, 200
Cold Leg 116,118, 216, 218
Steam Generator Primary Side 108, 208
Steam Generator Secondary Side 170-180, 270-280
Reactor Primary Pumps 113, 213
Pressurizer/ Accumulators 150 / 190, 290
Main Feed Water System (Main/Auxiliary) 182, 282 / 184, 284
Safety Injection System 191-192, 291-292
Charging System 193-194, 293-294
Reactor Core coolant channel (one channel) 335
Fuel Heat Structures 336
Break Valve 505
II. RESULTS
This result presents the key parameters during the 6-inch SBLOCA. Two groups (A&B) for comparison from
the results during the 6" break Cold Leg loss of coolant accident (SBLOCA) sequences with a scram. The fuel
rod is divided into six vertical nodes and also seventeen radial volumes. In order to investigate the temperature
distribution within the fuel rod,
The group (A) : In real case the reactor scram signal appears as the reactor pressure reached to the set- point
and consequently the control rods start to drop into the core. In the analysis, the calculations is performed with
and without reactivity feed-back, where the reactor scram signal is assumed to be activated at105 sec from the
start reactor operation. This group is comparison between the results with and without feedback Reactivity. In
group (A) the Separable model used to calculate the feedback Reactivity. The dragon neutronic code is used to
calculate the reactivity for all moderator densities (733~73.3 kg/m3
) and for (Doppler coefficient) fuel
temperatures (600, 800, 1000, and 1400K). Figures (2) and (3) demonstrate the variation of the coolant density
and reactivity, respectively through the core. With feedback, which simulate by the bold curve and regular
curve simulate without feed back. In case of without feed back the coolant density decreasing (20 kg/m3
) as the
coolant temperature increasing and maxim reactivity reached at -25 dollar at 400 sec. where in case with feed
back the negative reactivity increased till -55 dollar at 250 sec and density increased till reached (380 kg/m3
).
Figures (4) and (5) show core void fraction and core collapsed water level respectively from figure 4 due to
reactivity feedback the maximum void about 0.8 from figure 5 the minimum core water level is 7 m so there is
no core uncover with reactivity feedback in case without feedback core water level decreases rapidly and its
upper parts are uncovered for a period of time sufficient for heating up the core fuel elements respectively for
case without feed back PCT of 864 K occurs at nearly 430 sec. but in case with feed back the increasing
negative reactivity due to decreasing in density. The core power decreases and the coolant temperature
decreasing so the coolant density increasing again and the core water level increasing to cover the fuel elements
and the clad temperature decreasing reached (550 K) as shown in figure (6).
4. Reactivity Feedback Effect on the Reactor Behaviour…
www.ijmrem.com IJMREM Page 40
0
0.2
0.4
0.6
0.8
1
1.2
0 200 400 600 800 1000 1200
Time (sec)
Voidfraction
voidgfeed 335050000
voidgfeed 335060000
voidg 335050000
voidg 335060000
0
4
8
12
16
0 200 400 600 800 1000 1200
Time (sec)
corewaterlevel(m)
core levelfeed m
core level m
Fig. (5) core water level with and without feedback Reactivity with time.
Fig. (4) Void fraction in the core at the two upper zones with and without feedback
Reactivity with time.
5. Reactivity Feedback Effect on the Reactor Behaviour…
www.ijmrem.com IJMREM Page 41
200
400
600
800
1000
0 200 400 600 800 1000 1200
Time(sec)
Cladtemerature(K)
httempfeed 3360004 17 (K)
httempfeed 3360005 17 (K)
httemp 3360004 17 (K)
httemp 3360005 17 (K)
Fig. (6) cald temperature at fourth and fiveth axial nodes with and without
feedback Reactivity with time.
The second group (B) from results
For Tabular model: for a four-dimensional table (TABLE4a), the dragon code is used to calculate the reactivity
for:
1- Moderator densities (733~73.3 kg/m3
)
2- Fuel temperatures (600~1400K)
3- Moderator temperatures (560~620K)
4- Boron concentration (0-1200ppm)
In this group, both Separable and Tabular (table4) models are compared to analyze the reactivity feed-back
effect. During Cold Leg SBLOCA, the moderator temperature increases and density decreases, and this lead
the negative reactivity component, as shown in figures (7&8) for both separable and tabular models.
Fig. (7) Comparison between Separable and tabular feedback Reactivity for the coolant Density with
time
6. Reactivity Feedback Effect on the Reactor Behaviour…
www.ijmrem.com IJMREM Page 42
For separable model the total reactivity is just the summation of the coolant density reactivity and moderator and
fuel temperature reactivity. In tabular model, the total reactivity is a function of the four reactivities, since all
feed-back mechanisms are dependent the above three and boron concentration. Therefore, the absolute
reactivities calculated by the tabular model are smaller than the separable model, although the coolant density is
smaller than that calculated by separable model as shown in figures 8&9. As shown in figure 10 there is no core
uncover for two cases separable and tabular model.
Fig. (8) Reactivity for the reactor with time at Separable and tabular feedback Reactivity
Fig. (9) Void fraction in the core at the two upper zones at Separable and tabular feedback Reactivity
7. Reactivity Feedback Effect on the Reactor Behaviour…
www.ijmrem.com IJMREM Page 43
Fig. (10) Core water level with time at Separable and tabular feedback Reactivity
The power decreases with the decrease in the flow rate, ( SBLOCA) due to negative net reactivity feed-back
which is dominated by the negative density reactivity feed-back as the coolant heat-up (the coolant density
reactivity is much greater than Doppler reactivity). As the power decreases the fuel and clad temperatures also
begin to de crease, as shown in figure 11. The reactivity will increase due to Doppler effect, and this is the
positive reactivity component (Doppler reactivity).
Fig. (11) Clad temperature at fourth axial nodes with time at Separable and tabular feedback
Reactivity .
8. Reactivity Feedback Effect on the Reactor Behaviour…
www.ijmrem.com IJMREM Page 44
III. CONCLUSIONS
In this study, the characteristic of the 4-loop PWR Westinghouse nuclear power plant for reactivity feedback
coefficients, such as fuel temperature, moderator temperature, moderator density, as well as boron concentration
have been evaluated by using Dragon code. All reactivity coefficients of the reactor are negative. Two cases of
comparison during the worst consequences occur at 6-inch break size, case A comparison between T.H behavior
used Relap5 code with and without feedback (Separable model), and case B comparison between Separable and
tabular calculation. The results show that the importance of the reactivity feed-back on calculating the power
which the key parameter that controls the clad and fuel temperatures to maintain them below their melting point
and therefore prevent core uncover and fuel damage where the fuel temperature, clad temperature and core
water level are in the range.
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Nuclear Regulatory Commission Washington, DC 20555, December 2001.
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accident in PWR", Nuclear Engineering and Technology, 50 ,1277-1288, 2018.
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Science and Technology of Nuclear Installations, Vol. Article ID 814572, 2008.
6. Appendix D PIRT Plant and Scenario Descriptions, United States Nuclear Regulatory Commission,
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