Application of numerical methods to study the effect of axial conduction in plates and flow channels on the performance of plate heat exchangers

Abstract

Purpose

The purpose of this paper is to predict the plate heat exchanger performance when axial conduction in plates and in flow channels are present and fluids' viscosities are temperature dependent.

Design/methodology/approach

The approach to achieve the objective of the paper is deriving the governing equations and developing a computer program based on finite differences to solve them. The governing equations become dimensionless defining reference values and then discretized using FTBCS and FTCS methods. To solve the governing equations, the flow channel is divided into small elements in axial direction. Physical properties are constant for each element, while viscosity changes from one element to another one.

Findings

The effect of axial conduction in plates as well as in flow channels on temperature distributions, are studied individually and simultaneously. The program is run under four different conditions, namely: no axial conduction, axial conduction in the plates and in the flow channels, axial conduction in the plates only, and axial conduction in the flow channels only.In all the above cases, temperature distributions are achieved and characteristic curves are plotted. The numerical results are validated by comparing them with those published in an established reference carried out ignoring the effect of axial conduction, using the same plate geometry and flow details.

Originality/value

This paper gives valuable information and offers practical help to plate heat exchanger design engineer in order to choose the proper material for the plates as well as the right service and product fluids.

Citation

Mehrabian, M.A., Sheikhzadeh, G.A. and Khoramabadi, M. (2006), "Application of numerical methods to study the effect of axial conduction in plates and flow channels on the performance of plate heat exchangers", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 16 No. 1, pp. 67-83. https://doi.org/10.1108/09615530610636964