scholarly journals Effect of baffle cut and baffle spacing on pressure drop in shell and tube heat exchanger with U tubes

Author(s):  
Igor Martic ◽  
Aleksandar Maslarevic ◽  
Nikola Milovanovic ◽  
Miloš Markovic

A general procedure for heat exchanger design has been presented in the Heat Exchanger Design Handbook (HEDH) [1], but no precise criterion for determining baffle cut nor baffle  spacing has been offered, and the emphasis is only on heat exchanger’s permissible range of application. In this paper, an optimization program has been used to calculate pressure drop, fluid velocity, heat power, overall heat transfer coefficient and middle temperature difference for various baffle cut and baffle spacing for the same type of heat exchanger, using the procedure in HEDH. This could be considered as complementary to the HEDH recommendations and can be used by designers and, generally, engineers for determining the right baffle cut and baffle spacing for their specific cases.

Author(s):  
Torsten Berning

This paper describes the development of a numerical algorithm and a graphical method that can be employed in order to determine the overall heat transfer coefficient inside heat exchangers. The method is based on an energy balance and utilizes the spreadsheet application software Microsoft Excel™. The application is demonstrated in an example for designing a single pass shell and tube heat exchanger that was developed in the Department of Materials Technology of the Norwegian University of Science and Technology (NTNU) where water vapor is superheated by a secondary oil cycle. This approach can be used to reduce the number of hardware iterations in heat exchanger design.


2021 ◽  
pp. 252-252
Author(s):  
Navid Bozorgan ◽  
Ashkan Ghafouri ◽  
Ehsanolah Assareh ◽  
Seyed Mohammad Safieddin Ardebili

The present study modifies the structural design of a shell-and-tube heat exchanger (STHE) by considering two key parameters such as the maximization of the overall heat transfer coefficient and minimization of the total pressure drop. Five geometric design variables which include the tube inside diameter, tube outside diameter, pitch size, baffle spacing, and the tube length are investigated for optimization. The governing equations for design and optimization of the STHE are evaluated; and the optimum design parameters are obtained by Bees Algorithm (BA). The selection of the important design parameters to achieve the proper design is evaluated by fixing each of these parameters, while the other the design parameters are selected as variable to optimize the effectiveness. Compared with the original STHE, the overall heat transfer coefficient is increased by 22.78 % with the minimum increase in the total pressure drop by 1.8%.


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.


1985 ◽  
Vol 6 (1) ◽  
pp. 26-30 ◽  
Author(s):  
O. M. BRAGINA ◽  
V. L. LELCHUK ◽  
A. G. SOROKIN ◽  
A. V. TURKIN ◽  
K. F. SHUISKAYA

AIChE Journal ◽  
2016 ◽  
Vol 63 (6) ◽  
pp. 1907-1922 ◽  
Author(s):  
Caroline de O. Gonçalves ◽  
André L. H. Costa ◽  
Miguel J. Bagajewicz

Author(s):  
S. V. Sridhar ◽  
R. Karuppasamy ◽  
G. D. Sivakumar

Abstract In this investigation, the performance of the shell and tube heat exchanger operated with tin nanoparticles-water (SnO2-W) and silver nanoparticles-water (Ag-W) nanofluids was experimentally analyzed. SnO2-W and Ag-W nanofluids were prepared without any surface medication of nanoparticles. The effects of volume concentrations of nanoparticles on thermal conductivity, viscosity, heat transfer coefficient, fiction factor, Nusselt number, and pressure drop were analyzed. The results showed that thermal conductivity of nanofluids increased by 29% and 39% while adding 0.1 wt% of SnO2 and Ag nanoparticles, respectively, due to the unique intrinsic property of the nanoparticles. Further, the convective heat transfer coefficient was enhanced because of improvement of thermal conductivity of the two phase mixture and friction factor increased due to the increases of viscosity and density of nanofluids. Moreover, Ag nanofluid showed superior pressure drop compared to SnO2 nanofluid owing to the improvement of thermophysical properties of nanofluid.


2015 ◽  
Vol 62 (4) ◽  
pp. 509-522 ◽  
Author(s):  
R. Dharmalingam ◽  
K.K. Sivagnanaprabhu ◽  
J. Yogaraja ◽  
S. Gunasekaran ◽  
R. Mohan

Abstract Cooling is indispensable for maintaining the desired performance and reliability over a very huge variety of products like electronic devices, computer, automobiles, high power laser system etc. Apart from the heat load amplification and heat fluxes caused by many industrial products, cooling is one of the major technical challenges encountered by the industries like manufacturing sectors, transportation, microelectronics, etc. Normally water, ethylene glycol and oil are being used as the fluid to carry away the heat in these devices. The development of nanofluid generally shows a better heat transfer characteristics than the water. This research work summarizes the experimental study of the forced convective heat transfer and flow characteristics of a nanofluid consisting of water and 1% Al2O3 (volume concentration) nanoparticle flowing in a parallel flow, counter flow and shell and tube heat exchanger under laminar flow conditions. The Al2O3 nanoparticles of about 50 nm diameter are used in this work. Three different mass flow rates have been selected and the experiments have been conducted and their results are reported. This result portrays that the overall heat transfer coefficient and dimensionless Nusselt number of nanofluid is slightly higher than that of the base liquid at same mass flow rate at same inlet temperature. From the experimental result it is clear that the overall heat transfer coefficient of the nanofluid increases with an increase in the mass flow rate. It shows that whenever mass flow rate increases, the overall heat transfer coefficient along with Nusselt number eventually increases irrespective of flow direction. It was also found that during the increase in mass flow rate LMTD value ultimately decreases irrespective of flow direction. However, shell and tube heat exchanger provides better heat transfer characteristics than parallel and counter flow heat exchanger due to multi pass flow of nanofluid. The overall heat transfer coefficient, Nusselt number and logarithmic mean temperature difference of the water and Al2O3 /water nanofluid are also studied and the results are plotted graphically.


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

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