Simulations of Flow in a Solar Roof Collector Driven by Natural Convection

Tan BT, Lew MQ, Ong KS, 16th Australasian Fluid Mechanics Conference, Crown Plaza, Gold Coast, Australia,2-7 December 2007, 2007

The solar roof collector is modelled as a two dimensional air gap with one heated wall. The Boussinesq approximation is used to model the density variation. Four different air gap heights were simulated, namely 0.07m, 0.014m, 0,21m and 0.28m for a 2m long solar roof collector. The tilt angle of the solar collector was also varied between 15 degress and 55 degrees from horizontal. Predictions of velocities and mass flow rates in the air-gap are presented together with streamlines showing air flow patterns. The simulations show that a 0.14m air gap height at higher inclination angles is optimal for ventilation.