A Simulation of the Thermal Performance of a Small Solar Chimney Already Installed in a Building

Abstract

In this paper we present a theoretical study of a small solar chimney. The dimensions of the solar chimney channel are 1.95 m high, 1.70 m wide, and 0.24 m deep. The channel of the solar chimney has in its backside a metallic plate as a solar heat absorber, and it is attached to a concrete wall, which acts as storage and thermal insulation. On the front part of the chimney a glass cover is used to decrease the heat losses to the exterior. For this theoretical study, the steady-state energy balance equations were solved numerically for each element of the solar chimney. The results showed the temperature profiles for the glass cover, the air inside the channel, and the metallic plate. Also, the air mass flow rate was determined. When solar irradiance increases from 100 to 700 W/m2, the maximum instantaneous efficiency of the system varies from 28% to 37%, and also, the volumetric flow rate increases from 61 to 147 m3/h.