Numerical investigation of the ventilation performance of a solar chimney

Abstract

This article reports a two dimensional, steady state, numerical simulation of the air flow inside a solar chimney with a fixed absorber height but various air gap widths and inlet aperture heights. The ventilation performance of the solar chimney in terms of the mass flow rate is presented. The numerical results show that the mass ow rate is an increasing function of surface emissivity and input heat flux. It is also found that the mass flow rate is up to 59% higher with a surface emissivity of 0.9 than that with a zero surface emissivity. This investigation shows the importance of radiation heat transfer in a solar chimney system. The numerical results further show that the ventilation performance of the solar chimney is more sensitive to the change in the air gap width than to the change in the inlet aperture height, and an optimum inlet aperture height can be identified. © Austral. Mathematical Soc. 2011.