Thermal analysis, pressure drop and exergy loss of energy efficient shell, and triple meshed helical coil tube heat exchanger

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.

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Effect of internal and external corrugated surfaces on the characteristics of heat transfer and pressure drop in a concentric tube heat exchanger

International Journal of Thermal Sciences ◽

10.1016/j.ijthermalsci.2021.106930 ◽

2021 ◽

Vol 165 ◽

pp. 106930

Author(s):

Abdelaziz Begag ◽

Rachid Saim ◽

Said Abboudi ◽

Hakan F. Öztop

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Pressure Drop ◽

Tube Heat Exchanger ◽

Corrugated Surfaces

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Performance analyses of helical coil heat exchangers. The effect of external coil surface modification on heat exchanger effectiveness

Archives of Thermodynamics ◽

10.1515/aoter-2016-0032 ◽

2016 ◽

Vol 37 (4) ◽

pp. 137-159 ◽

Cited By ~ 16

Author(s):

Rafał Andrzejczyk ◽

Tomasz Muszyński

Keyword(s):

Heat Transfer ◽

Surface Modification ◽

Heat Exchanger ◽

Heat Exchangers ◽

Helical Structure ◽

Nuclear Industry ◽

Helical Coil ◽

Tube Heat Exchanger ◽

High Heat Transfer ◽

Coil Heat

Abstract The shell and coil heat exchangers are commonly used in heating, ventilation, nuclear industry, process plant, heat recovery and air conditioning systems. This type of recuperators benefits from simple construction, the low value of pressure drops and high heat transfer. In helical coil, centrifugal force is acting on the moving fluid due to the curvature of the tube results in the development. It has been long recognized that the heat transfer in the helical tube is much better than in the straight ones because of the occurrence of secondary flow in planes normal to the main flow inside the helical structure. Helical tubes show good performance in heat transfer enhancement, while the uniform curvature of spiral structure is inconvenient in pipe installation in heat exchangers. Authors have presented their own construction of shell and tube heat exchanger with intensified heat transfer. The purpose of this article is to assess the influence of the surface modification over the performance coefficient and effectiveness. The experiments have been performed for the steady-state heat transfer. Experimental data points were gathered for both laminar and turbulent flow, both for co current- and countercurrent flow arrangement. To find optimal heat transfer intensification on the shell-side authors applied the number of transfer units analysis.

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