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用实验和数值计算的方法研究了横流对单孔短距冲击换热特性的影响规律.结果表明:①在实验研究范围内,冲击靶面平均努塞尔数Nuav,is随横流的增大而增大;②冲击靶面前区努塞尔数Nufia随横流的增大而减小,这是因为壁面附近x负向流动的气流流速绝对值变小,换热削弱;③靶面冲击点附近及冲击靶面后区努塞尔数Nubia随横流的增大而增大,原因是在冲击点上游出现的马蹄涡的旋涡方向和冲击射流自身形成的卷吸涡拉伸涡对方向相同,这两种涡的叠加使该区域冲击靶面的换热得到增强.
The influence of cross flow on the heat transfer characteristics of single hole short impact was studied by means of experiment and numerical calculation.The results showed that: (1) Within the range of experimental study, the average Nusselt number of the target surface increases with the increase of cross flow (2) The Nusselt number Nufia in front of the impact target decreases with the increase of cross-flow because the absolute value of the flow velocity of the negative flow in the vicinity of the wall becomes smaller and the heat exchange is weakened. In the vicinity of the impact point of the target surface and The Nusselt Nubia in the back of impact target increases with the increase of cross-flow because the vortex direction of the horseshoe vortex which appears upstream of the impact point is the same as that of the entrained vortex drawn by the impact jet itself The superposition of vortexes enhances the heat transfer of the target surface in this area.