抄録
The aim of this basic study is to reveal the temporal and spatial heat transfer performance around an isothermally heated sphere placed in a uniform, downwardly directed flow using a micro-foil heat flow sensor, whose response time is about 0.02s. Experiments were carried out using air with a Grashof number of 3.3×10^5 and with Reynolds numbers up to 2200. Three flow patterns appeared; a chaotic flow, a steady 2-D separated flow and an unsteady 3-D separated flow. And it is also clarified that the appearance of these flow patterns and the time-averaged heat transfer performance are strongly influenced by the blockage effect. Furthermore, the wake structure of the sphere was revealed by using a hot wire anemometer and flow visualization.
