scholarly journals Numerical Simulation of Heat Exchanger for Analyzing the Performance of Parallel and Counter Flow

2021 ◽  
Vol 16 ◽  
pp. 145-152
Author(s):  
Farid Ahmed ◽  
Md Minaruzzaman Sumon ◽  
Muhtasim Fuad ◽  
Ravi Gugulothu ◽  
AS Mollah

Heat exchangers are almost used in every industry. Among them, shell and tube heat exchangers are covering around 32% of the total heat exchanger. Numerical simulation of the Computational models is playing an important role for the prototypes including the Heat Exchanger Models for the improvement in modeling. In this study, the CFD analysis of parallel and counter flow shell and tube heat exchanger was performed. Following project, looked into the several aspects and these are the temperature, velocity, and pressure drop and turbulence kinetic energy along with the heat exchanger length. Hot water was placed in tube side and cold water was placed in shell side of the heat exchanger. Shell side cold temperature was increasing along the heat exchanger length. On the other side, tube side hot water temperature was decreasing along the tube length. This effect was more significance in counter flow rather than the parallel flow. Velocity was more fluctuating in the shell side due to presence of the baffles. Also following the same reason, pressure drop was higher in the shell side cold water rather than the tube side hot water. To measure the turbulence effect, turbulence kinetic energy was determined. Turbulence was decreasing first part of the shell and tube heat exchanger. But, it was increasing along through the rest part heat exchanger. All these observations and the outcomes are evaluated and then further analyzed

2013 ◽  
Vol 860-863 ◽  
pp. 754-757
Author(s):  
Can Zheng ◽  
Fei Wang ◽  
Yong Gang Lei

A new type of helical baffles heat exchanger is presented in this paper. Comparative study, through numerical simulation, was undertook between the new helical baffles heat exchanger and segmental baffle board heat exchanger in shell side flow and heat exchange characteristics. Fluid medium in the shell side is air. At the same velocity in the same flow conditions, pressure drop of helical baffles heat exchangers fell by an average of 26.8% compared with segmental baffle board heat exchangers, and the unit pressure drop of the heat transfer ratio of helical baffles heat exchanger increased by an average of 40.6%.


Author(s):  
Ragunath L ◽  
Mohanraj C ◽  
Suriya kumar S ◽  
Sasi Kumar S ◽  
Balamurugan C

The turn of events and execution enhancement of shell and tube heat exchanger is an issue of incredible test and part of arising early innovation. The exhibition enhancement would serve an extraordinary commitment to assuage the swelled working expenses just as energy emergency. This paper grandstands every one of the experimental outcomes got from the constant framework investigation in different working conditions. Further it addresses examination for a few shell-and-tube heat exchangers with segmental confounds with various point parametric variety. The framework distinguishing proof has been done utilizing CFD investigation. The consolidated outcomes as for same shell-side stream rate show that, the heat move co-proficient of the heat exchanger with astounds is higher than that of the heat exchanger without perplexes, while the shell-side pressing factor drop of the previous is even a lot of lower than that of the last mentioned. Further upgrade methods ought to be consolidated to improve shell-side heat move dependent on a similar stream rate. The near investigation of heat move coefficient per unit pressure drop shows that the Segmental Baffle Heat exchanger have critical execution advantage over Segmental Baffle Heat exchanger for similar mathematical arrangements.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Swanand Gaikwad ◽  
Ashish Parmar

AbstractHeat exchangers possess a significant role in energy transmission and energy generation in most industries. In this work, a three-dimensional simulation has been carried out of a shell and tube heat exchanger (STHX) consisting of segmental baffles. The investigation involves using the commercial code of ANSYS CFX, which incorporates the modeling, meshing, and usage of the Finite Element Method to yield numerical results. Much work is available in the literature regarding the effect of baffle cut and baffle spacing as two different entities, but some uncertainty pertains when we discuss the combination of these two parameters. This study aims to find an appropriate mix of baffle cut and baffle spacing for the efficient functioning of a shell and tube heat exchanger. Two parameters are tested: the baffle cuts at 30, 35, 40% of the shell-inside diameter, and the baffle spacing’s to fit 6,8,10 baffles within the heat exchanger. The numerical results showed the role of the studied parameters on the shell side heat transfer coefficient and the pressure drop in the shell and tube heat exchanger. The investigation shows an increase in the shell side heat transfer coefficient of 13.13% when going from 6 to 8 baffle configuration and a 23.10% acclivity for the change of six baffles to 10, for a specific baffle cut. Evidence also shows a rise in the pressure drop with an increase in the baffle spacing from the ranges of 44–46.79%, which can be controlled by managing the baffle cut provided.


2021 ◽  
Author(s):  
praveen math

Abstract Shell and Tube heat exchangers are having special importance in boilers, oil coolers, condensers, pre-heaters. They are also widely used in process applications as well as the refrigeration and air conditioning industry. The robustness and medium weighted shape of Shell and Tube heat exchangers make them well suited for high pressure operations. The aim of this study is to experiment, validate and to provide design suggestion to optimize the shell and tube heat exchanger (STHE). The heat exchanger is made of acrylic material with 2 baffles and 7 tubes made of stainless steel. Hot fluid flows inside the tube and cold fluid flows over the tube in the shell. 4 K-type thermocouples were used to read the hot and cold fluids inlet and outlet temperatures. Experiments were carried out for various combinations of hot and cold water flow rates with different hot water inlet temperatures. The flow conditions are limited to the lab size model of the experimental setup. A commercial CFD code was used to study the thermal and hydraulic flow field inside the shell and tubes. CFD methodology is developed to appropriately represent the flow physics and the procedure is validated with the experimental results. Turbulent flow in tube side is observed for all flow conditions, while the shell side has laminar flow except for extreme hot water temperatures. Hence transition k-kl-omega model was used to predict the flow better for transition cases. Realizable k- epsilon model with non-equilibrium wall function was used for turbulent cases. Temperature and velocity profiles are examined in detail and observed that the flow remains almost uniform to the tubes thus limiting heat transfer. Approximately 2/3 rd of the shell side flow does not surround the tubes due to biased flow contributing to reduced overall heat transfer and increased pressure loss. On the basis of these findings an attempt has been made to enhance the heat transfer by inducing turbulence in the shel l side flow. The two baffles were rotated in opposite direction to each other to achieve more circulation in the shell side flow and provide more contact with tube surface. Various positions of the baffles were simulated and studied using CFD analysis and th e results are summarized with respect to heat transfer and pressure loss.


2021 ◽  
Vol 6 (1) ◽  
pp. 69-75
Author(s):  
Taiwo O. Oni ◽  
Ayotunde A. Ojo ◽  
Daniel C. Uguru-Okorie ◽  
David O. Akindele

A shell-and-tube heat exchanger which was subjected to different flow configurations, viz. counter flow, and parallel flow, was investigated. Each of the flow configurations was operated under two different conditions of the shell, that is, an uninsulated shell and a shell insulated with fiber glass. The hot water inlet temperature of the tube was reduced gradually from 60 oC to 40 oC, and performance evaluation of the heat exchanger was carried out. It was found that for the uninsulated shell, the heat transfer effectiveness for hot water inlet temperature of 60, 55, 50, 45, and 40 oC are 0.243, 0.244, 0.240, 0.240, and 0.247, respectively, for the parallel flow arrangement. For the counter flow arrangement, the heat transfer effectiveness for the uninsulated shell are 2.40, 2.74, 5.00, 4.17, and 2.70%, respectively, higher than those for the parallel flow. The heat exchanger’s heat transfer effectiveness with fiber-glass-insulated shell for the parallel flow condition with tube hot water inlet temperatures of 60, 55, 50, 45, and 40 oC are 0.223, 0.226, 0.220, 0.225, and 0.227, respectively, whereas the counter flow condition has its heat transfer effectiveness increased by 1.28, 1.47, 1.82, 1.11, and 1.18%, respectively, over those of the parallel flow.


2012 ◽  
Vol 560-561 ◽  
pp. 156-160
Author(s):  
Lin Ping Lu ◽  
Liang Ying

The experiments on heat transfer coefficient, pressure drop and thermal stress were done to heat exchangers with corrugated tubes and staight tubes. By analyising and comparing the heat transfer coeffient, pressure drop in tube side and shell side and axial force and stress, some conclusions can be conducted that the corrugated tube heat exchanger has better heat transfer coeffient, higher pressure drop and much lower stress caused by temperatur difference, also, it has obvious advantages under the circumstance of low Reynolds number and high temperature difference.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Amarjit Singh ◽  
Satbir S. Sehgal

In this study, the experimental analysis was performed on the shell-and-tube type heat exchanger containing segmental baffles at different orientations. In the current work, three angular orientations (θ) 0°, 30°, and 60° of the baffles were analyzed for laminar flow having the Reynolds number range 303–1516. It was observed that, with increase of Reynolds number from 303 to 1516, there was a 94.8% increase in Nusselt number and 282.9% increase in pressure drop. Due to increase of Reynolds number from 303 to 1516, there is a decrease in nondimensional temperature factor for cold water (ω) by 57.7% and hot water (ξ) by 57.1%, respectively.


1994 ◽  
Vol 15 (3) ◽  
pp. 42-56 ◽  
Author(s):  
T. PEKDEMIR ◽  
T. W. DAVIES ◽  
L. E. HASELER ◽  
A. D. DIAPER

Author(s):  
K. Mohammadi ◽  
W. Heidemann ◽  
H. Mu¨ller-Steinhagen

A semi-analytical model is presented for the evaluation of the performance factor of the inlet zone of an E type shell and tube heat exchanger without leakage flows. The performance factor is defined as the ratio of dimensionless heat transfer coefficients and pressure drops of both vertical and horizontal baffle orientation and therefore facilitates the decision between horizontal and vertical baffle orientation of shell and tube heat exchangers. The model allows the calculation of the performance factor of the inlet zone as a function of the baffle cut, the shell-side Reynolds number at the inlet nozzle and the Prandtl number of the shell-side fluid. The application of the model requires the knowledge of the performance factor of water at baffle cut equal to 24% of the shell inside diameter. For the development of the model a numerical data basis is used due to the lack of experimental data for shell and tube heat exchangers with different baffle orientations. The numerical data are obtained from CFD calculations for steady state conditions within a segmentally baffled shell and tube heat exchanger following the TEMA standards. Air, water and engine oil with Prandtl numbers in the range of 0.7 to 206 are used as shell-side fluids. The semi-analytical model introduced for the performance factor predicts the CFD results with a relative absolute error less than 5%. The presented model has to be validated with further experimental data and/or numerical results which explain the effect of baffle orientation on the shell-side heat transfer coefficient and pressure drop in order to check the general applicability.


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