Experimental and numerical investigation of thermal and fluid-flow processes in a matrix heat exchanger

Abstract

The need for compact heat exchangers has led to the development of many types of surfaces that enhance the rate of heat transfer, among them the matrix heat exchangers. These heat exchangers consist of a series of perforated plates mutually separated and sealed by spacers. The goal of this research was to investigate the heat transfer process of matrix heat exchangers on the air side, at the close to ambient conditions. The research was conducted in two directions-experimental research and CFD research. The experimental investigation was carried out over a perforated plate package with the porosity of 25.6%. The air/water matrix heat exchanger was heated by hot water and was installed in an experimental chamber at which entrance was a fan with the variable flow rate and heated by hot water. The thermocouples were attached to the surface of the perforated plate at the upwind and downwind sides, as well as at the inlet and the outlet of the chamber. During each experiment, the thermocouple readings and the air and water-flow and temperatures were recorded. In the numerical part of the research, the matrix heat exchangers with different plate porosity from 10 to 50% were investigated. The results of the numerical simulations were validated against the experimental results. On the basis of the experimental and numerical results, equations for heat transfer as the function of Reynolds number and geometrical parameters was established.

Experimental and numerical studies of the effect of perforation configuration on heat transfer enhancement of pin fins heat sink

“…The thermophysical properties of the working fluid (air) are determined based on the average bulk temperature T b in Equation ( 10) above. 33,38,43,44 Considering the same pumping power, the overall improvement factor (hydrothermal performance) is characterized as the ratio between the enhancement ratios of heat transfer and friction factors. It is defined by the following expressions (Shaeri et al, 2009).…”

“…The thermophysical properties of the working fluid (air) are determined based on the average bulk temperature T b in Equation (10) above 33,38,43,44 …”

Analysis of the performance of the shell and tube heat exchanger: Influence of pipe layout and diameter

“…The main problem in the application of these devices is the complexity of determining the output parameters or determining the optimal construction that provides the required parameters. The difficulties that arise in the selection of these devices are the result of complex heat exchange processes [3]. Namely, the visual appearance, dimensions, and even the available data on the basic geometry are not enough to know about the capabilities of the device.…”