干旱区生态环境知识资源中心

Experimental studies were performed to investigate the fluid now arid local heat transfer around two cubes arranged in tandem on a flat plate turbulent boundary layer. The Reynolds number, based on the cube height d, ranged from 4.0 x 10(3) to 3.2 x 10(4). The thickness of the turbulent boundary layer delta was delta/d greater than or equal to 2.17. The surface temperature distribution around the cubes was measured with termocouples under conditions of constant heat flux. The effect of spacing b between two cubes was clarified in the range of 0.33 less than or equal to b/d less than or equal to 1.33. In the case of b/d greater than or equal to 0.67. the horseshoe vortex is formed in front of each cube. However, at b/d = 0.33, it does not form in front of the 2nd cube. The local heat transfer is high in the horseshoe vortex regions arid the flow reattaching regions. The average Nusselt numbers of 1st cube, Nu(1), and 2nd cube, Nu(2), are expressed as Nu(1) = 0.24Re(0.66) and Nu(2) = 0.27Re(0.64), respectively. They are virtually unaffected by the spacing. However, that of base plate between two cubes, Nu(p12), has a maximum value of Nu(p12) = 0.47Re(0.60) at about b/d = 0.67.