Analysis of a gas-particle direct-contact heat exchanger with two-phase radiation effect

Abstract

A direct-contact heat exchange using particle-suspended gas as a heat transfer medium is analyzed with an extended emphasis on the radiation, i.e., considering the radiation by both gas and particles. While the Runge-Kutta method is used for a numerical analysis of the momentum and energy equations, the finite volume method is utilized to solve the radiative transfer equation. The present study shows a notable effect by the gas radiation in addition to the particle radiation, especially when varying the chamber length as well as the gas and particle mass flow rate. When the gas and particle mass pow rate is raised, the gas temperature in the particle heater increases as the gas absorption coefficient increases, which is different from the results for the small-scale heat exchanger. However, the scattering effects by particles were found to be insignificant.