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CFD Analysis of Shell and Tube Heat Exchanger with Effect of Varying Baffles Inclination

Contents

Abstract

1) Introduction2) Computational Fluid Dynamics3) Literature Review4) Objective5) Gap in Study6) Methodology and Planning of work7) Conclusions and Future Scope of Work

References

ABSTRACT

The energy present in the exit stream of many energy conversion devices such as I.C engine gas turbine etc. goes as waste, if not utilized properly. The present work has been carried out with a view to predicting the performance of a shell and tube heat exchanger in the light of waste heat recovery application. The performance of the heat exchanger has been evaluated by using the CFD package Fluent for different baffle angles and different number of baffles. An attempt has been made to calculate the performance of the above heat exchanger by varying the baffle angles and the result so obtained will be compared. The performance parameters pertaining to heat exchanger such as effectiveness, overall heat transfer coefficient, energy extraction rate etc., will be reported in this work. The shell side design of a shell-and-tube heat exchanger is explored in this study. The baffle cut and baffles inclination dependencies of the heat transfer coefficient and the pressure drop are investigated by numerically modelling a small heat exchanger. The flow and temperature fields inside the shell are resolved using a commercial CFD software tool ANSYS FLUENT

CFD Analysis of Shell and Tube Heat Exchanger with Effect of Varying Baffles Inclination

1) Introduction

Heat exchangers are one of the mostly used equipment in the process industries. Heat exchangers are used to transfer heat between two process streams. One can realize their usage that any process which involve cooling, heating, condensation, boiling or evaporation will require a heat exchanger for these purpose. Process fluids, usually are heated or cooled before the process or undergo a phase change. Different heat exchangers are named accordingto their application. For example, heat exchangers being used to condense are known as condensers, similarly heat exchanger for boiling purposes are called boilers. Performance and efficiency of heat exchangers are measured through the amount of heat transfer using least area of heat transfer and pressure drop. A better presentation of its efficiency is done by calculating over all heat transfer coefficient. Pressure drop and area required for a certain amount of heat transfer, provides an insight about the capital cost and power requirements (Running cost) of a heat exchanger. Usually, there is lots of literature and theories to design a heat exchanger according to the requirements.Heat exchangers are of two types:-Where both media between which heat is exchanged are in direct contact with each other is direct contact heat exchanger,Where both media are separated by a wall through which heat is transferred so that they never mix, indirect contact heat exchanger.A typical heat exchanger, usually for higher pressure applications up to 552 bars, is the shell and tube heat exchanger. Shell and tube type heat exchanger is an indirect contact type heat exchanger. It consists of a series of tubes, through which one of the fluids runs. The shell is the container for the shell fluid. Generally, it is cylindrical in shape with a circular cross section, although shells of different shape are used in specific applications. For this particular study the shell considered is a one pass shell. A shell is the most commonly used due to its low cost and simplicity, and has the highest log-mean temperature-difference (LMTD) correction factor. Although the tubes may have single or multiple passes, there is one pass on the shell side, while the other fluid flows within the shell over the tubes to be heated or cooled. The tube side and shell side fluids are separated by a tube sheet.

Baffles are used to support the tubes for structural rigidity, preventing tube vibration and sagging and to divert the flow across the bundle to obtain a higher heat transfer coefficient. Baffle spacing (B) is the centre line distance between two adjacent baffles, Baffle is provided with a cut (Bc) which is expressed as the percentage of the segment height to shell inside diameter. Baffle cut can vary between 15% and 45% of the shell inside diameter. In the presentstudy 36% baffle cut (Bc) is considered. In general, conventional shell and tube heat exchangers result in high shell-side pressure drop and formation of recirculation zones near the baffles. Most of the researches now a day are carried on helical baffles, which give better performance then singlesegmental baffles but they involve high manufacturing cost, installation cost and maintenance cost.The effectiveness and cost are two important parameters in heat exchanger design. So, In order to improve the thermal performance at a reasonable cost of the Shell and tube heat exchanger, baffles in the present study are provided with some inclination in order to maintain a reasonable pressure drop across the exchanger.The complexity with experimental techniques involves quantitative description of flow phenomena using measurements dealing with one quantity at a time for a limited range of problem and operating conditions. Computational Fluid Dynamics is now an established industrial design tool, offering obvious advantages. By modelling the geometry as accurately as possible, the flow structure and the temperature distribution inside the shell are obtained.

Design of shell and tube heat exchanger

There are several designs in shell and tube heat exchanger. Even though, thebasic principle is still the same. The tubes may be straight or bent in the shape of a U, called U-tubes. This U-tubes type typically use in nuclear power plants. The heat exchanger is used to boil water recycled from a surface condenser into steam to drive a turbine to produce power. Most shell-and-tube heat exchangers are 1, 2, or 4 pass designs on the tube side. This refers to the number of times the fluid in the tubes passes through the fluid in the shell. In a single pass heat exchanger, the fluid goes in one end of each tube and out the other.

Heat Transfer

Heat transfer is the terms use for thermal energy from a hot to a colder body.Theoretically on a microscopic scale, thermal energy is related is to the kinetic energy of molecules. The greater is material's temperature, the greater the thermal agitation of its constituent molecules. Then the regions containing greater molecular kinetic energy will pass this energy to regions with less kinetic energy. So when a physical body like an object or fluid, is at a different temperature than its surroundings or another body, heat transfer will occurs in such a way that the body and the surroundings reach thermal equilibrium.Heat transfer always occurs from a hot body to a cold one, a result of the secondlaw of thermodynamics. Where there is a temperature difference between objects in proximity, heat transfer between them can never be stopped but can only be slowed down. Transfer of thermal energy can only occurs through three ways which is conduction, convection and radiation or any combination of that.In case of study which relate to shell and tube heat exchanger it only consistof heat transfer by conduction and convection.

2) Computational Fluid Dynamics: CFD is useful for studying fluid flow, heat transfer; chemical reactions etc by solving mathematical equations with the help of numerical analysis.CFD resolve the entire system in small cells and apply governing equations on these discrete elements to find numerical solutions regarding pressure distribution, temperature gradients. [9] This software can also build a virtual prototype of the system or device before can be apply to real-world physics to the model, and the software will provide with images and data, which predict the performance of that design. More recently the methods have been applied to the design of internal combustion engine, combustion chambers of gas turbine and furnaces, also fluid flows and heat transfer in heat exchanger. The development in the CFD field provides a capability comparable to other Computer Aided Engineering (CAE) tools such as stress analysis codes. [11] Basic Approach to using CFD

a) Pre-processor :( Establishing the model) Identify the process or equipment to be evaluated. Represent the geometry of interest using CAD tools. Use the CAD representation to create a volume flow domain around the equipment containing the critical flow phenomena. Create a computational mesh in the flow domain.

b) Solver: Identify and apply conditions at the domain boundary. Solve the governing equations on the computational mesh using analysis software.

c) Post processor :( Interpreting the results) Post-process the completed solutions to highlight findings. Interpret the prediction to determine design iterations or possible solutions, if needed.

APPLICATION OF CFD:

CFD not just spans on chemical industry, but a wide range of industrial and non industrial application areas which is in below: Aerodynamics of aircraft and vehicle. Combustion in IC engines and gas turbine in power plant. Loads on offshore structure in marine engineering. Blood flows through arteries and vein in biomedical engineering. Weather prediction in meteorology. Flow inside rotating passages and diffusers in turbo-machinery. External and internal environment of buildings like wind loading and heating or Ventilation system. Mixing and separation or polymer mouldings in chemical process engineering. Distribution of pollutants and effluent in environmental engineering.

ANSYS:

Ansys is the finite element analysis code widely use in computer aided engineering(CAE) field. ANSYS software help us to construct computer models of structure, machine, components or system, apply operating loads and other design criteria, study physical response such as stress level temperature distribution, pressure etc. In Ansys following Basic steps are followed:

During pre processing the geometry of the problem is defined. Volume occupied by fluid is divided into discrete cells (the mesh). The mesh may be uniform or non uniform. The physical modelling is defined. Boundary condition is defined. This involves specifying the fluid behaviour of the problem. For transient problem boundary condition are also defined. The simulation is started and the equations are solved iteratively as steady state or transient. Finally a post procedure is used for the analysis and visualisation of the resulting problem.

Fluent

Fluent is the world's largest provider of commercial computational fluiddynamics (CFD) software and services. Fluent offers general-purpose CFD software for a wide range of industrial applications, along with highly automated, specifically focused packages. Fluent also offers CFD consulting services to customers worldwide.The staff at Fluent consists mostly of individuals with highly technical backgrounds as applied CFD engineers. In addition, fluent employs experts in computational methods, mesh generation, and software development. Fluent's clients are the market leaders and the largest companies in industries such as automotive, aerospace, chemical and materials processing, power generation,biomedical, HVAC, and electronics. Fluent is committed to furthering the body of knowledge on CFD, and to improving the effectiveness of computer modelling as a design and analysis tool in general. They invest in both internal research and development, and participate in collaborations with leading academic establishments, governments, and industry groups. They continue to explore and implement strategic alliances with both hardware and software providers to achieve greater synergy and efficiency for our customers.Fluent's mission has been clear from the beginning: to work closely withcustomers to understand their fluid-flow challenges, to provide both software and services tailored to their needs, and to continually measure our success as a function of theirs. As a result of their continuing efforts to fulfil the mission, they have enjoyed outstanding user loyalty throughout their history.

Fluent is a state-of-the-art computer program for modelling fluid flow and heattransfer in complex geometries. Fluent provides complete mesh flexibility, including the ability to solve the flow problems using unstructured meshes that can be generated about complex geometries with relative ease. Supported mesh types include 2D triangular/ quadrilateral, 3D tetrahedral/ hexahedral/ pyramid/ wedge/ polyhedral, and mixed (hybrid) meshes. Fluent also allows you to refine or coarsen your grid based on the flow solution. Fluent is written in the C computer language and makes full use of the flexibility and power offered by the language. Consequently, true dynamic memory allocation, efficient data structures, and flexible solver control are all possible. In addition, fluentuses a client/server architecture, which allows it to run as separate simultaneousprocesses on client desktop workstations and powerful computer servers. Thisarchitecture allows for efficient execution, interactive control, and complete flexibility between different types of machines or operating systems. All functions required to compute a solution and display the results are accessible in fluent through an interactive, menu-driven interface.

Choosing a Turbulence Model

Turbulence arises due to the instability in the flow. Turbulent flows contain a wide range of length, velocity and time scales and solving all of them makes the costs of simulations large. Therefore, several turbulence models have been developed with different degrees of resolution. There are several turbulence models available in CFD-software including the Large Eddy Simulation (LES) and Reynolds Average Navier- Stokes (RANS). There are several RANS models available depending on the characteristic of flow, e.g., Standard k- model, k- RNG model, Realizable k- , k- and RSM (Reynolds Stress Model) models. [5]

3) Literature Review M. Thirumarimurugan, T.Kannadasan and E.Ramasamy [1] have investigated heat transfer study on a solvent and solution by using Shell and Tube Heat Exchanger. In which Steam is taken as the hot fluid and Water and acetic acid-Water miscible solution taken as cold fluid. A series of runs were made between steam and water, steam and Acetic acid solution .The flow rate of the cold fluid is maintained from 120 to 720 lph and the volume fraction of Acetic acid is varied from 10-50%. Experimental results such as exchanger effectiveness, overall heat transfer coefficients were calculated. . MATLAB program was used to simulate a mathematical model for the outlet temperatures of both the Shell and Tube side fluids. The effect of different cold side flow rates and different compositions of cold fluid on the shell outlet temperature, tube outlet temperature and overall heat transfer coefficients were studied. Result shows that the overall effectiveness of heat exchanger was found to increase with decrease in composition of water. From the comparisons it can be said that the mathematical model developed and simulated using MATLAB and compared with the experimental values for the system is very close. Usman Ur Rehman [5] had investigated an un-baffled shell-and-tube heat exchanger design with respect to heat transfer coefficient and pressure drop by numerically modeling. The heat exchanger contained 19 tubes inside a 5.85m long and 108mm diameter shell. The flow and temperature fields are resolved using a commercial CFD package and it is performed for a single shell and tube bundle and is compared with the experimental result .Standard k- Model is used first to get the flow distribution but it is not good for predicting the boundary layer separation and impinging flows. For this reason, Realizable k model is used with standard and then Non-equilibrium wall functions. The non-equilibrium wall functions with Realizable k- model give better results than standard k- model. The pressure drop heat transfer still are being over predicted by almost 25%, which is probably due to y+ values limitations at tube walls .Thus in order to avoid this and to include the low Reynolds modification SST k- model is also used. Because it uses both k - and k- model in the region of high and low Reynolds number respectively. SST k- model has provided the reliable results with the y+ limitations. Thus the modeling can also be improved by using Reynolds Stress Models, but with higher computational costs and the enhanced wall functions are not used. The heat transfer is found to be poor because the most of the shell side fluid by-passes the tube bundle without interaction. Thus the design can be modified to achieve the better heat transfer in two ways. Either, the shell diameter is reduced or tube spacing can be increased .Thus the design can further be improved by creating cross-flow regions in such a way that flow doesnt remain parallel to the tubes. It will allow the outer shell fluid to mix with the inner shell fluid and will automatically increase the heat transfer. Jian-Fei Zhang, Ya-Ling He, Wen-Quan Tao [7] developed a method for design and rating of shell-and-tube heat exchanger with helical baffles based on the public literatures and the widely used BellDelaware method for shell-and-tube heat exchanger with segmental baffles (STHXSB). The accuracy of present method is validated with experimental data. Four design cases of replacing original STHXsSB by STHXsHB are taken. In case 1 comprehensive performance is greatly improved by using tube-core with 40 degree middle overlapped helical baffles, and the pressure drop is 39% lower and 16% decrease in heat transfer area. In case 2 the usage of tube-core with 40 deg middle overlapped helical baffles can reduce the over-all pressure drop by 46% and the heat transfer area is 13% lower. In case 3 pressure drop of the heat exchanger with 40 deg middle-overlapped helical baffles is equivalent, the heat transfer area reduced by 33%. In case 4 20 deg middle-overlapped helical baffles were adopted and the pressure drop is 33% lower than that of the original unit with 10% decrease in heat transfer area. And comparison result shows that all shell and tube heat exchanger with helical baffles have better performance than the original heat exchanger with segmental baffles. Muhammad Mahmood Aslam Bhutta, Nasir Hayat, Muhammad Hassan Bashir, Ahmer Rais Khan,Kanwar Naveed Ahmad, Sarfaraz Khani[9] , It focuses on the applications of Computational Fluid Dynamics (CFD) in the field of heat exchangers. It has been found that CFD employed for the fluid flow mal-distribution, fouling, pressure drop and thermal analysis in the design and optimization phase. Different turbulence models such as standard, realizable and RNG, k , RSM, and SST k - with velocity-pressure coupling schemes such as SIMPLE, SIMPLEC, PISO and etc. have been adopted to carry out the simulations. Conventional methods used for the design and development of Heat Exchangers are expensive. CFD provides cost effective alternative, speedy solution and eliminate the need of prototype, it is limited to Plate, Shell and Tube, Vertical Mantle, Compact and Printed Circuit Board Exchangers but also flexible enough to predict the fluid flow behaviour to complete heat exchanger design and optimization involving a wide range of turbulence models and Integrating schemes the k - turbulence model is most widely employed design and optimization .The simulations results ranging from 2% to 10% with the experimental studies. In some exceptional cases, it varies to 36%. arko Stevanovi, Gradimir Ili, Nenad Radojkovi, Mia Vuki, Velimir Stefanovi, Goran Vukovi [12] has developed an iterative procedure for sizing shell-and-tube heat Exchangers according to given pressure drop and the thermo-hydraulic calculation and the geometric optimization on the basis of CFD technique have been carried out. A numerical study of three-dimensional fluid flow and heat transfer is described. The baffle and tube bundle was modelled by the 'porous media' concept. Three turbulent models were used for the flow processes. The velocity and temperature distributions and total heat transfer rate were calculated by using PHOENICS Version 3.3 code. Due to the effects of eddy-viscosity the effect of different turbulence models on both flow and heat transfer is significant. It was concluded that Chen-Kim modification of the standard k turbulence model give the best agreement to the experimental data. The optimization of flow distribution is an essential step in heat exchanger design optimization because an optimal flow distribution can result in a higher heat transfer rate and lower pressure drop. Ender Ozden, Ilker Tari. [13] Has investigated the design of shell and tube heat exchanger by numerically modelling in particular the baffle spacing, baffle cut and shell diameter dependencies of heat transfer coefficient and pressure drop. The flow and temperature fields are resolved by using a commercial CFD package and it is performed for a single shell and single tube pass heat exchanger with a variable number of baffles and turbulent flow. The best turbulent model among the one is selected to compare with the CFD results of heat coefficient, outlet temperature and pressure drop with the Bell-Delaware method result. By varying flow rate the effect of the baffle spacing to shell diameter ratio on the heat exchanger performance for two baffle cut value is investigated. Three turbulence models are taken for the first and second order discretizations to mesh density. By comparing with the Bell-Delaware results the k- realizable turbulence model is selected as the best simulation approach. By varying baffle spacing between 6 to 12 , and the baffle cut values of 36%and 25% for 0.5 and 2kg/s flow rate ,the simulation results are compared with the results from the kern and Bell-Delaware methods. It is observed that the CFD simulation results are very good with the Bell-Delaware methods and the differences between Bell-Delaware method and CFD simulations results of total heat transfer rate are below 2% for most of the cases. Apu Roy, D.H.Das [14] the present work has been carried out with a view to predicting the performance of a shell and finned tube heat exchanger in the light of waste heat recovery application. Energy available in the exit stream of many energy conversion devices such as I.C engine gas turbine etc goes as waste, if not utilized properly. The performance of the heat exchanger has been evaluated by using the CFD package fluent 6.3.16 and the available values are compared with experimental values. By considering different heat transfer fluids the performance of the above heat exchanger can also be predict. The performance parameters of heat exchanger such as effectiveness, overall heat transfer coefficient, energy extraction rate etc, have been taken in this work. Gaddis [15], Schlunder [16], Mukherjee [17].The heat exchanger model used in this study is a small sized one, as compared to the main stream, all of the leakage and bypass streams do not exist or are negligible, Ender Ozden and Ilker Tari [18] , Uday Kapale and Satish Chand[19], Thirumarimurugan et al. [20]. Baffles are used to support the tubes for structural rigidity, preventing tube vibration and sagging and to divert the flow across the bundle to obtain a higher heat transfer coefficient. Baffle spacing (B) is the centre line distance between two adjacent baffles, Sparrow and Reifschneider [21], Li and Kottke [22], Su Thet Mon Than et al. [23]. Baffle is provided with a cut (Bc) which is expressed as the percentage of the segment height to shell inside diameter. Baffle cut can vary between 15% and 45% of the shell inside Proceedings of the National Conference on Trends and Advances in Mechanical Engineering, YMCA University of Science & Technology, Faridabad, Haryana, Oct 19-20, 2012 diameter, Kakac and Liu [24], Gay et al. [25], Emerson [26]. In the present study 36% baffle cut (Bc) is considered. In general, conventional shell and tube heat exchangers result in high shell-side pressure drop and formation of recirculation zones near the baffles. Most of the researches now a day are carried on helical baffles, which give better performance then single segmental baffles but they involve high manufacturing cost, installation cost and maintenance cost. The effectiveness and cost are two important parameters in heat exchanger design. So, In order to improve the thermal performance at a reasonable cost of the Shell and tube heat exchanger, baffles in the present study are provided with some inclination in order to maintain a reasonable pressure drop across the exchanger Yong-Gang Lei et al. [27]. The complexity with experimental techniques involves quantitative description of flow phenomena using measurements dealing with one quantity at a time for a limited range of problem and operating conditions. Computational Fluid Dynamics is now an established industrial design tool, offering obvious advantages Versteeg and Malalasekera [28]. In this study, a full 360 CFD model of shell and tube heat exchanger is considered. By modelling the geometry as accurately as possible, the flow structure and the temperature distribution inside the shell are obtained. In this study, a small shell-and-tube heat exchanger is modelled for CFD simulations. A commercial CFD package, STAR CCM+ version6 [30], is used together with Hyper Mesh for mesh generation software. Sensitivity of the simulation results to modelling choices such as mesh and turbulence model is investigated. After selecting a suitable mesh, a discretization scheme and a turbulence model, simulations are performed for two different shell side flow rates by varying 36 % baffle cut. The simulation results are used for calculating shell side heat transfer coefficient and pressure drop

4) Objective:

The shell side design of a shell-and-tube heat exchanger is explored in this study. The baffle cut and baffles inclination dependencies of the heat transfer coefficient and the pressure drop are investigated by numerically modelling a small heat exchanger. The flow and temperature fields inside the shell are resolved using a commercial CFD software tool ANSYS FLUENT. In this present work, attempts were made to investigate the impacts of various baffle inclination angles on fluid flow and the heat transfer characteristics of a shell-and-tube heat exchanger for three different baffles inclination angles namely 0, 45 and -45. The simulation results for various shell and tube heat exchangers, one with segmental baffles perpendicular to fluid flow and two with segmental baffles inclined to the direction of fluid flow are compared for their performance. The results are expected to be sensitive to the turbulence model selection. For a given baffle cut, the heat exchanger performance is investigated by varying mass flow rate and baffle inclination angle. From the CFD simulation results, the shell side outlet temperature, pressure drop, recirculation near the baffles, heat transfer, optimal mass flow rate and the optimum baffle inclination angle for the given heat exchanger geometry are determined

The main objective of this project is first designing a simple shell and tube heat exchanger using 3D CAD solid modelling software. Then the Computational Fluid Dynamics CFD analysis of Shell and Tube heat exchanger using ANSYS Fluent as a tool to determine the Temperature distribution and the Heat transfer coefficients of the heat exchanger with and without baffles and also at different inclinations of the baffles.

Given a Shell and Tube heat Exchanger with a single shell and a single tube. The working fluid for the heat exchanger is water. Hot water will be circulated from the shell and cold water in the tube. We will try to find out the following:

1) Temperature distribution in parallel flow without baffles2) Heat transfer coefficient in the case of parallel flow without baffles.3) Temperature distribution in counter flow without baffles4) Heat transfer coefficient in the case of counter flow without baffles5) The effect of segmented baffles on Temperature distribution and Heat transfer coefficient6) The effect of number of baffles in the range of shell7) The effect of inclination of the baffles on the results.

The above results will be estimated for the three baffle angles 0 Degree, 45 Degree and -45 Degree. All the results like shell side outlet temperature, pressure drop, recirculation near the baffles, heat transfer will be compared for the above three cases. Then the results will be compiled to comment about the optimum number and optimum inclinations of the baffles.

Based on the above analysis the optimum number, placement and inclination of the baffles can be found out to improve the temperature distribution and the Heat transfer coefficient of the heat exchanger.

5) Gaps in study:

Although a lot of research has been carried out on Shell and Tube heat exchanger there are still some gaps in the research which needs to be filled in the future. A sufficient research has been done on the different configurations of the shell and tube heat exchanger to improve its heat transfer coefficients and to improve the efficiency of the system. Also lots of researchers have used the CAE (Computer Aided Engineering) Tools like Ansys Fluent to simulate the real life conditions and predict the performance of Shell and Tube Heat Exchangers. The effects of Baffles are also researched by many researchers.

But still there is some gap as not much research can be found on the different configuration of baffles, the optimum number of baffles, the proper inclination of the baffles etc. Our proposed work is a step in this direction to fill this gap. The effects of maximum parameters related to baffles are dealt in this work.

6) Methodology and Planning of Work

The methodology involved in the research work includes the following.

1) Modelling of Shell and Heat Exchanger Using 3D CAD Software2) Importing the Model in the Ansys Environment3) Analysis of the Shell and Tube Heat Exchanger model with the Help of Ansys Fluent4) Analysing the results of Temperature distribution and Heat transfer coefficient

The above steps (1-4) are repeated for various configurations of Shell and Tube Heat Exchangers. That is for heat exchanger with baffles, for heat exchanger with baffles of different inclination and for different number of baffles. Based on the above results of different configurations we will arrive at the optimum arrangement of the baffles in the Shell and Tube Heat Exchanger.

A simple shell and tube heat exchanger with vertical segmented baffles is shown in the fig below:

A simple shell and tube heat exchanger with segmented baffles inclined at an angle theta with the vertical is shown in the fig below:

The planning for the research work is given below:

Task Time duration

1) Designing of 3D models on CAD 2 weeks2) Analysis on ANSYS Fluent 4 Weeks3) Compilation of Results 3 Weeks4) Report writing and Thesis 2 Weeks

7.) Conclusions & Future Scope of Work

Baffles are definitely useful in increasing the overall heat transfer coefficient of the shell and tube heat exchanger. But the arrangements and number of baffles are also important in maximizing their effect. Conventional methods used for the design and development of Heat Exchangers are expensive. CFD provide alternative to cost effectiveness speedy solution to heat exchanger design and optimization.CFD results are the integral part of the design process and it have eliminated the need of prototype .due to the development of CFD models, the use of CFD is no longer a specialist activity. It is accessible to process engineers, plant operator and manager. Further study needs to be carried out for performance optimization of shell and tube heat exchanger by varying tube & shell diameter, no. of tubes etcCFD is still a developing art in prediction of erosion/ corrosion due to lack of suitable mathematical models to represent physical process. New flow modelling strategies can be developed for flow simulation in shell and tube heat exchanger.

REFERENCES

[1] M. Thirumarimurugan, T.Kannadasan and E.Ramasamy, Performance Analysis Of Shell And Tube Heat Exchanger Using Miscible System, American Journal Of Applied Sciences 5 (5): 548-552, 2008. [2] K. Sudhakara Rao, Analysis Of Flow Mal distribution In Tubular Heat Exchangers By Fluent, National Institute Of Technology Rourkela ,2007. [3] M.R. Salimpour, Heat Transfer Coefficients Of Shell And Coiled Tube Heat Exchangers, Isfahan University Of Technology, Iran, 2008. [4] Yusuf Ali Kara, Ozbilen Gurarasa, A Computer Program For Designing Of Shell-And-Tube Heat Exchangers, Applied Thermal Engineering University Of Ataturk, Turkey, 2004. [5] Usman Ur Rehman, Heat Transfer Optimization of Shell-And-Tube Heat Exchanger through CFD Studies, Chalmers University of Technology, 2011. [6] Huadong Li And Volker Kottke, Effect Of The Leakage On Pressure Drop And Local Heat Transfer In Shell-And-Tube Heat Exchangers For Staggered Tube Arrangement, Inl. J. Heat Mass Transfer, Elsevier Science Ltd., 1998. [7] Jian-Fei Zhang, Ya-Ling He, Wen-Quan Tao, A Design And Rating Method For Shell-And-Tube Heat Exchangers With Helical Baffles, Journal Of Heat Transfer, May 2010. [8] Huadong Li And Volker Kottke, Effect Of Baffle Spacing On Pressure Drop And Local Heat Transfer In Shell-And-Tube Heat Exchangers For Staggered Tube Arrangement, Inl. J. Heat Mass Transfer, Elsevier Science Ltd., 1998. [9] Muhammad Mahmood Aslam Bhutta, Nasir Hayat, Muhammad Hassan Bashir, Ahmer Rais Khan, Kanwar Naveed Ahmad, Sarfaraz Khan5, CFD Applications In Various Heat Exchangers Design: A Review, Department Of Mechanical Engineering, University Of Engineering & Technology, Applied Thermal Engineering, 2011. [10] Philip J Stop ford, Recent Application of CFD Modeling in Power Generation Metal and Process Industries, Second International Conference on CFD in Mineral and Process Industries, CSIRO, Melbourne, Australia, 1999. [11] Khairun Hasmadi Othman, CFD Simulation Of Heat Transfer In Shell And Tube Heat Exchanger, University Malaysia Pahang, April 2009.

[12] arko Stevanovi, Gradimir Ili, Design Of Shell-And-Tube Heat Exchangers By Using CFD Technique, University Of Ni, Fr, 2002. [13] Ender Ozden, Ilker Tari, Shell Side CFD Analysis of A Small Shell And Tube Heat Exchanger, Middle East Technical University, 2010. [14] Apu Roy, D.H.Das, CFD Analysis Of A Shell And Finned Tube Heat Exchanger For Waste Heat Recovery Applications, National Institute Of Technology, 2011.

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[17]. Mukherjee, R., Practical Thermal Design of Shell-and-Tube Heat Exchangers, Begell House.Inc, New York, 2004.

[18]. Ender Ozden, Ilker Tari, Shell side CFD analysis of a small shell-and-tube heat exchanger, Energy Conversion and Management 51 (2010), pp. 1004 1014.

[19]. Uday Kapale, C., Satish Chand, Modeling for shell-side pressure drop for liquid flow in shell-and-tube heat exchanger, International Journal of Heat and Mass Transfer 49 (2006), pp. 601610 [20]. Thirumarimurugan, M., Kannadasan, T., Ramasamy, E., Performance Analysis of Shell and Tube Heat Exchanger Using Miscible System, American Journal of Applied Sciences 5 (2008), pp. 548-552.

[21]. Sparrows, E. M., Reifschneider, L. G., Effect of inter baffle spacing on heat transfer and pressure drop in a shell-and-tube heat exchanger, International Journal of Heat and Mass Transfer 29 (1986), pp. 1617-1628.

[22]. Li, H., Kottke, V., Effect of baffle spacing on pressure drop and local heat transfer in shell and tube heat exchangers for staggered tube arrangement, Int. J. Heat Mass Transfer 41 (1998), 10, pp. 13031311

[23]. Su Thet Mon Than, Khin Aung Lin, Mi Sandar Mon, Heat Exchanger Design, WorldAcademy of Science, Engineering and Technology 46, 2008.

[24]. Kakac, S., Liu, H., Heat Exchangers Selection, Rating and Thermal Design, CRC press,second ed, Washington D.C., 2002, pp. 318335

[25]. Gay, B., Mackley, N.V., Jenkins, J. D., Shell-side heat transfer in baffled cylindrical shell andtube exchangers, Int. J. Heat Mass Transfer 19 (1976), pp. 995-1002.

[26]. Emerson, W.H., Shell-side pressure drop and heat transfer with turbulent flow in segmentally baffled shelltube heat exchangers, Int. J. Heat Mass Transfer 6 (1963), pp. 649668.

[27]. Yong-Gang Lei, Ya-Ling He, Rui Li, Ya-Fu Gao, Effects of baffle inclination angle on flow and heat transfer of a heat exchanger with helical baffles, Chemical Engineering and Processing 47 (2008), pp. 23362345.

[28]. Versteeg, H.K., Malalasekera, W., An introduction to computational fluid dynamics: the finite volume method, first ed, Essex (England): Pearson, 1995.

[29] Incropera FP, Dewitt DP. Fundamentals of heat and mass transfer. 4th ed. New York: J. Wiley; 1996.

[30] STAR-CCM+ version 6. Starccm+ 6 Users Guide. CDADAPCO Inc.