Investigation of buoyancy air flow inside solar chimney using CFD technique

Abstract

A solar chimney is a way of improving the natural ventilation of buildings by using convection of air heated by passive solar energy. It results in air flows because of the difference of the density varied with vertical direction. Therefore, the objective of this study was to investigate the ventilation efficiency of solar chimney using experimental and computation fluid dynamics (CFD) methods. In the simulation, models of buoyancy force and radiation heat transfer were applied to compute air flow inside the chimney. The influence of heat flux in a range of 400-800 W/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and 1 to 2 m height of solar chimney on the ventilation efficiency was investigated. It was found that the ventilation efficiency and air flow rate are increased with increasing the heat flux and height of solar chimney. In addition, CFD simulation shows good agreement with experimental results.