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在冲击雷诺数为1×104~6×10~4条件下,针对不同气膜孔开孔率两种层板模型,实验研究了靶面、冲击面、扰流柱面压力系数分布以及冲击射流、绕流、溢流的局部损失和整体损失系数.结果表明:靶面由于滞止区加速流动向着壁面射流区减速流动过渡,压力系数出现二次峰值.两股冲击射流在靶面相汇形成低压力系数区,相汇后翻卷回冲击面形成低压力系数区.距离冲击孔较远的两排扰流柱表面压力系数分布受雷诺数影响较大.雷诺数Re≤3×10~4时,压力分布表现为横掠单管的绕流特征.雷诺数Re≥4×10~4时,压力分布表现为翻卷绕流特征.溢流损失系数最大,绕流损失系数次之,冲击射流损失系数最小.开孔率减小一半,冲击射流损失和绕流损失变化较小,气膜孔溢流损失升高至少4倍.
Under the impact Reynolds number of 1 × 104 ~ 6 × 10 ~ 4, according to the model of the porosity of different film holes, the model of the target surface, the impact surface, the pressure coefficient distribution of the spoiler cylinder and the impact jet , Partial loss of flow and overflow, and total loss coefficient.The results show that the pressure coefficient appears quadratic peak due to the accelerating flow of stagnant zone toward the slowed flow in the jet region of the wall, and the two impinging jets form low Pressure coefficient zone, and then rewound back to the impact surface to form a low pressure coefficient zone.The distribution of surface pressure coefficient of two rows of spoiler farther away from the impact hole is greatly influenced by the Reynolds number Reynolds number Re ≤3 × 10-4, The pressure distribution shows the characteristics of flow around a single pipe, and when the Reynolds number is greater than or equal to 4 × 10 ~ 4, the pressure distribution is characterized by the characteristics of overturning flow, with the largest overflow loss coefficient, the second is the bypass coefficient, the other is the jet loss coefficient Minimum.The opening ratio is reduced by half, impact jet loss and flow loss change is small, the film hole overflow loss increased at least 4 times.