Study of Heat Transfer and Fluid Flow in Heat Exchanger and Improve Their Energy Efficiency

Abstract

In this study, two rows of fins from a fintube plate recuperator heat exchanger with two different materials, ceramic and steel, have been simulated by cfx software. First, by using experimental data that are in access, the independency from network and the confirmation of pattern authenticity have been checked. Equations from the equations of steadystate (SST) model k–د‰ have been used for applying turbulence terms in dominant. After network stabilization in greatest Reynolds number, the flow in the recuperator heat exchanger has been studied for two other Reynolds numbers. From the simulations, it is concluded that by increasing Reynolds number the temperature of fins' surfaces, outlet fluid temperature, and the temperature of tubes' surfaces will be increased, but totally the amount of overall heat transfer in time unit will be increased by the increase in Reynolds number. Also, it is observed that changing the material from steel to ceramic does not have that much difference for heat transfer in flow in low temperatures but the temperature of fins' surfaces for different materials and similar boundary status is different.