Vol. 05,Special Issue 01, (ICOSD-2020) January 2020, Available Online:
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“THERMAL ANALYSIS OF HEAT EXCHANGER VARYING BAFFLES GEOMETRY APPLYING FINITE ELEMENT METHOD”
Abhishek Joshi1, Nilesh Sharma2, Sumit Kumar Barange2, Manisha Joshi4 Research Scholar1, Assistant Professor2, Assistant Professor3, Assistant Professor4
Department of Mechanical Engineering
Lakshmi Narain College of Technology & Science (RIT), Indore (M.P.)1,2,3 AITS, Udaipur (Raj)4
Abstract- Heat Exchanger is a setup which is used in industries to transfer thermal energy between two or more fluids which are at different temperatures and in thermal contact.
Heat Exchanger is frequently utilized in many applications like petroleum refining, refrigeration, cooling, nourishment industry, etc. Among various sorts of heat exchangers, manufacturing of shell and-tube Heat Exchanger or heat exchanger is easy to manufacture and install and have multi-reason application. This present work performs a survey of researches and works deals with impacts of various baffles sorts on pressure loss and heat transfer in heat exchanger. The research also includes modeling of Heat Exchanger with variety of baffles shapes and the performance is analyzed on the basis of outlet temperature and velocity.
Keywords: Baffles, Shell and Tube Heat Exchanger, HX, Pressure drop, heat transfer coefficient, fouling, Baffle shape.
1. INTRODUCTION
Heat Exchanger is a mechanical operated device used to reduce energy consumption, and installed to perform work such as preheating a fluid. Boiler, power plant, heating, Refrigeration, ventilating, and air conditioning (HVAC) are having Heat Exchanger utility. In simple terms, a Heat Exchanger is a heat exchanger. A Heat Exchanger may be defined as equipment which transfers energy from a hot fluid to a cold fluid, either maximum or minimum rate within minimum investment and running cost.
In this process never two fluids mixed with each other. This device provides a flow of thermal energy between two or more fluids at different temperatures. Shell and tube heat exchangers are most versatile type of heat exchanger; they use in a wide variety of engineering applications like power generation, waste heat recovery, manufacturing industry, air-conditioning, refrigeration, space applications, petrochemical industries etc.
1.1 Shell and Tube Heat Exchanger
A Shell and tube heat exchanger consists of a shell (a large vessel) with a bundle of tubes inside it. Two fluids, of different starting temperatures, flow through tubes (the tube side) and the other flows outside the tubes but inside the shell (the shell side). The fluids can be either liquids or gases on either the shell or the tube side.
2. LITERATURE SURVEY
Pranita Bichkar et al., (2018) Numerical model is used to compute and compare the shell side fluid performance of shell and tube heat exchanger. Simulations are performed for different baffles.Number of baffles gives serious effects on pressure drop. Single segmental baffles show the formation of dead zones with no heat transfer.[1]
Swapnil S. Kamthe and Shivprakash B. Barve, (2017) This paper survey for impacts of various baffles sorts on pressure loss and heat transfer in heat exchanger. [2]
Asif Ahmed et al., (2017) FEM 3D numerical simulation of two segmentally baffled shell-and-tubeheat exchangers (STHXs) with plain tube bundle (STHXsPT) and annular- finned tube bundle (STHXsFT) has been performed. [3]
Halil Bayram and Gökhan Sevilgen, (2017) In this present study, numerical and theoretical analysis are used to investigate the effect of the variable baffle spacing on the thermal characteristics of a small shell and tube heat exchanger.[4]
Saurabh Sharma and Ritesh Kumar Dewangan, (2017)5 This paper review design of Baffle plates and its different orientations to improve overall performance of shell and tube heat exchanger.[5]
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M. Jin et al., (2017) Paper research for influence of baffle curvature radius of the sextant fan baffled shell and tube heat exchanger (SFTHX) on the shell side pressure drop.
Based on the numerically simulation results, [6]
A. A. Musilim et al., (2017) In present study, attempts were made to investigate the effects of varying baffle cut sizes at various mass flow rates on temperature and pressure drop of a shell-and-tube heat exchanger for zero degree (0°) baffle inclination angle. [7]
Swapnil S. Kamthe and Shivprakash B. Barve, (2017) A survey of exploratory research work is performed to test the impacts of various baffles on pressure loss and heat transfer in heat exchanger. [8]
J. Bala Bhaskara Rao and V. Ramachandra Raju, (2016) In the present study, CFD analysis for circular models and elliptical models of the STHE with various baffle cuts at different tube orientations is conducted.[9]
Xin Gu et al., (2016) Effect of main structural parameters of shutter baffle heat exchanger is studied in the article. The effects of structural parameters are analyzed. Using the field synergy principle, the heat transfer enhancement mechanisms are analyzed. [10]
Sandeep M and U Sathish kumar (2015) In this paper, a study of triangle, rectangular and round cross sections for a shell and tube heat exchanger is presented. [11]
Ajith kumar M.S. et al., (2014) In this paper, an effort has made for Computational Fluid Dynamic (CFD) analysis of a single pass parallel flow Shell and Tube Heat Exchanger (STHX) with different baffle inclinations. [12]
Neeraj kumar and Pradeep kumar Jhinge, (2014) In present work, single pass, counter flow shell and tube heat exchanger containing segmental baffles with various orientations has been tested to find heat transfer rate and pressure drop at different Reynolds number in laminar flow.[13]
Amarjit Singh and Satbir S. Sehgal, (2013) In this study, th7e experimental analysis was performed on the shell-and-tube type heat exchanger containing segmental baffles at different orientations. [14]
2.1 Objective
The main objectives that to be studied in this work is:-
1. To prepare the CAD model in the SolidWorks software by using the actual parametric dimensions.
2. To prepare finite element model in the Computer aided analysis software by specifying the approximate element size for meshing.
3. To study the flow patterns for heat exchanger.
4. To study the velocity and pressure distribution.
5. To study the static pressure drop, total pressure drop, and energy loss in the flow pattern generated.
2.2 Problem Formulation
In present research work the modal is to be created using SolidWorks. The research is focused to the thermal analysis of the Heat Exchanger using SolidWorks simulation software. Various Baffles are to be used to improve heat transfer rate of heat exchanger.
Following is the part modeled geometry and dimensions in SolidWorks:
Figure: 1 Without Baffles Geometry and Half Baffles Geometry
Vol. 05,Special Issue 01, (ICOSD-2020) January 2020, Available Online:
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Figure: 2 Circular Baffles Geometry and Square Baffles Geometry
Figure: 3 Boundary Conditions Definition
The material used for model is SS 316 and dimensions of the Heat Exchanger tube assembly are taken as:-
Tube id = 404 mm
Inlet/Outlet cylinder id = 610 mm
Number of tubes = 25
Heat Exchanger overall size = 17767 X 4252ϕ 3. METHODOLOGY
The research starts with survey of existing research performed by various researchers. The problem is then is to be identified from research survey. Next step is to create a model of heat exchanger by considering all dimensions as per problem definition. CFD analysis type is required to select as a analysis method.
Meshing is one of the important part of analysis using software’s. Meshing type is required to be select while completing model generation. Thermal conductivity, velocity, inlet temperatures etc. are required to define for all considered problem models. Boundary conditions are required to define before performing or run CFD analysis. Once the analysis is run one can obtain results in the form of outlet parameters or variables.
4. ANALYSIS AND RESULTS COMPARISON
All cases are modeled and analyzed to find output parameters in term of temperature, velocity, Mach no., PRN no., pressure and specific heat.
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Figure: 4 Fluid Thermal Conductivity and Mach No.
Figure: 5 Temperature and Pressure
Figure: 6 PRN No. and Specific Heat 4.1 Results Table
Table 2 Results Against Baffles Type Baffles
Type
Fluid Term Conductiv ity W/mK
Mach Numb er
Tube Outlet Temperat ure (K)
Shell Outlet Temperat ure (K)
Tube Outlet Veloci ty (m/s)
Shell Outlet Veloci ty (m/s)
Pressure (Pa)
PRN Numb er
Specif ic Heat J/kgK Withou
t 0.0289 0.0012 471.32 356.34 1.507 0.626 101326.
68 0.8732 2190.7 Half 0.0287 0.0012 417 343.44 1.31 0.571 101324.
99 0.8998 2190.7 Circula
r 0.0289 0.0013 428.3 357.4 1.255 0.582 101324.
99 0.8732 2189.9 Square 0.0304 0.0012 433.33 336 1.332 0.538 101326.
52 0.8732 2194.6 4.2 Results Comparison
Vol. 05,Special Issue 01, (ICOSD-2020) January 2020, Available Online:
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Figure: Tube Outlet Temperature and Shell Outlet Temperature Comparison
Figure: Tube Outlet Velocity and Shell Outlet Velocity Comparison 5. DISCUSSION AND CONCLUSION
The first thing to highlight is that the presented work is presented with analysis performed at SolidWorks software, this can be concluded that the software is capable of performing research in the field of Heat Exchanger and heat exchanger analysis and their performance improvement.
Wit hou t
Half Circ ular
Squ are Tube Outlet
Temperature (K)
471.32 417 428.3 433.33 380
390 400 410 420 430 440 450 460 470 480
Temperature (K)
Tube Outlet Temperature (K)
Plai
n Half Circ ular
Squ are Shell Outlet
Temperature (K)
356.34 343.44 357.4 336 325
330 335 340 345 350 355 360
Temperature (K)
Shell Outlet Temperature (K)
Plai
n Half Circ ular
Squ are Tube Outlet
Velocity (m/s) 1.507 1.31 1.255 1.332 0
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6
Velocoty m/s
Tube Outlet Velocity (m/s)
Plai n
Hal f
Circ ula r
Squ are Shell Outlet
Velocity (m/s) 0.626 0.571 0.582 0.538 0.48
0.5 0.52 0.54 0.56 0.58 0.6 0.62 0.64
Velocoty m/s
Shell Outlet Velocity
(m/s)
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The Heat Exchanger is designed with shell and tubes type heat exchanger concept, various shapes of baffles are modeled to analyze the performance difference of problem formulated in present work. The ammonia gas is used in tube and hot water is used in shell of Heat Exchanger, it is necessary to feed cooled ammonia and hot water in the Heat Exchanger system and at outlet it is must to achieve cooled water. As far as velocity concern it is desired to obtain low velocity at shell outlet, because low velocity will support to transfer heat at higher extent.
It is seen and analyzed that the water temperature falls 39.84% with Without Baffles case, 42.01% with half Baffles, 39.66% with circular baffles and 43.27% with square baffles. It is clear that the best results desired are obtained with square baffles and hence it is recommended for present model analyzed.
It is seen and analyzed that the water velocity falls 87.48% with Without Baffles, 88.58% with half Baffles, 88.36% with circular baffles and 89.24% with square baffles. It is clear that the best results desired are obtained with square baffles and hence it is recommended for present model analyzed.
REFERENCES
1. Pranita Bichkar et al., Study of Shell and Tube Heat Exchanger with the Effect of Types of Baffles, 2nd International Conference on Materials Manufacturing and Design Engineering, Procedia Manufacturing Volume 20,pp 195–200, 2018.
2. Swapnil S. Kamthe* and Shivprakash B. Barve, Effect of Different types of Baffles on Heat Transfer &
Pressure Drop of Shell and Tube Heat Exchanger: A review, International Journal of Current Engineering and Technology, MITCOE, & DIAT, Pune, AMET-2017, IJCET INPRESSO Special Issue-7,pp 358-362, 2017, March.
3. Asif Ahmed et al., Comparison of Performance of Shell-and-Tube Heat Exchangers with Plain and Annular-Finned Tube Bundle, Proceedings of the 1st International Conference on Mechanical Engineering and Applied Science (ICMEAS 2017).
4. Halil Bayram and Gökhan Sevilgen, Numerical Investigation of the Effect of Variable Baffle Spacing on the Thermal Performance of a Shell and Tube Heat Exchanger, Energies Volume 10, pp 1156, 2017.
5. Saurabh Sharma and Ritesh Kumar Dewangan, A Review on Shell and Tube Heat Exchanger (Sthx) Using Various Orientation Angle of Baffle, International Journal of Engineering Sciences & Research Technology, Volume 6 Issue 10, 2017, October
6. M. Jin et al., Optimization research of sextant fan baffle curvature radius in shell and tube heat exchanger, IOP Conference Series: Materials Science and Engineering, pp 231, 2017.
7. A. A. Musilim et al., Effect of Baffle Cut Sizes on Temperature and Pressure Drop at Various Mass Flow Rate in a Shell and Tube Heat Exchanger, International Journal of Engineering, Science and Mathematics, Vol. 6 Issue 1, 2017, March.
8. Swapnil S. Kamthe and Shivprakash B. Barve, Effect of Different types of Baffles on Heat Transfer &
Pressure Drop of Shell and Tube Heat Exchanger: A review, International Journal of Current Engineering and Technology, Special Issue-7, 2017, March.
9. J. Bala Bhaskara Rao and V. Ramachandra Raju, Numerical and heat transfer analysis of shell and tube heat exchanger with circular and elliptical tubes, International Journal of Mechanical and Materials Engineering (2016) Volume 11 Issue 6, pp 2 – 18, 2016.
10. Xin Gu et al., Heat transfer and flow resistance performance of shutter baffle heat exchanger with triangle tube layout in shell side, Advances in Mechanical Engineering, Vol. 8, Issue 3, pp 1–8, 2016.
11. Sandeep M and U Sathish kumar, CFD Investigation of Influence of Tube Bundle Cross-Section over Pressure Drop and Heat Transfer Rate, International Journal of Science, Engineering and Technology Research (IJSETR), Volume 4, Issue 5, 2015, May.
12. Ajith kumar M.S. et al., CFD Analysis to Study the Effects of Inclined Baffles on Fluid Flow in a Shell and Tube Heat Exchanger, Inte
13. Neeraj kumar and Pradeep kumar Jhinge, Effect of Segmental Baffles at Different Orientation on the Performances of Single Pass Shell and Tube Heat Exchanger rnational Journal of Research in Advent Technology, Vol.2, Issue 7, pp 164-175, 2014, July., International Journal of Engineering Trends and Technology (IJETT) – Volume 15 Number 9, 2014, Sep.
14. Amarjit Singh and Satbir S. Sehgal, Thermo hydraulic Analysis of Shell-and-Tube Heat Exchanger with Segmental Baffles, ISRN Chemical Engineering, Volume 2013, Article ID 548676.
