非均匀横流作用下冲击射流冷却的数值研究

运用数值计算的方法对非均匀横流作用下冲击射流冷却的流动和传热过程进行了三维数值研究,揭示出射流冲击孔和横流孔相对排列方式、射流雷诺数和横流雷诺数相对大小、射流孔中心至横流孔出口截面距离等因素对冲击射流冷却流动传热特性的影响。结果表明:若保持总的冷却流量不变,当横流雷诺数与射流雷诺数之比等于或大于0.5后,有横流时的冲击射流冷却局部努塞尔数比无横流时有较为显著的下降;在非均匀的横流作用下,对于叉排和顺排方式,由于射流和横流的相互作用,壁面温度分布呈现出复杂的特征;射流孔和横流孔呈顺排布置时,峰值努塞尔数所对应的射流驻点区向下游偏移。 

Numerical Investigation of Jet Impingement Cooling with Non-Uniform Crossflow

Three-dimensional numerical computation of the flow and heat transfer for the jet impingement cooling with non-uniform initial crossflow was conducted to investigate the effects of the jet-to-surface spacing,the impinging holes and crossflow holes arrangement,as well as the crossflow to jet Reynolds number ratio on the heat transfer characteristics.When the crossflow to jet Reynolds number ratios are equal or greater than 0.5,the jet impingement Nusselt numbers are obviously lower than that without crossflow under the same total cooling massflow rate.Under the action of non-uniform crossflow,the temperature distributions take complicated feature for both staggered and inline arrangements owing to the interaction of jet and crossflow.Compared to the case of staggered arrangement between jet holes and crossflow holes,the stations corresponding to peak Nusselt numbers for inline arrangement move downstream.