抄録
A numerical study is performed on unsteady natural convection heat transfer and fluid flow in a vertical cavity under microgravity. Consideration is given to the influence of Rayleigh number (Ra) on the thermal and velocity fields in a square cell with two opposing vertical side walls held at constant but different temperature with the remaining horizontal walls insulated. The governing boundary-layer equations are discretized by means of a finite-difference technique and numerically solved. It is disclosed from the study that: in free fall, the fluid temperature gradient is substantially decreased near the hot and cold vertical walls, (ii) but as time progresses, the dominant heat transfer mechanism switches from convection into conduction. A similar trend is seen at different Rayleigh numbers.
