气膜孔位置对气冷凹腔支板冷却效果影响分析

Effect of Position of Gas Film Hole on Cooling Performance of Air-cooled Concave Support Plate

为了解决一体化加力燃烧室中凹腔支板壁面温度过高的问题,提出了一种新的冷却结构方案,同时采用三维数值模拟方法针对不同气膜孔位置的结构模型进行计算,研究了气膜孔位置对额定工况下一体化加力燃烧室内气动热力性能的影响,重点研究了气膜孔位置对燃烧室内凹腔支板的引气率、壁面最高温度、后缘支板冷却效果等气动热力性能指标的影响。结果表明:引气率随着气膜孔位置靠后而线性增大且增长梯度逐渐减小,最大值相对于最小值增加了124.3%;后缘支板冷却效果随着气膜孔中心与来流方向所成角度α的增大不断上升,增大幅度为89.3%,冷却效果最终保持在0.35左右;随着气膜孔位置的不断后移,最高壁温不断降低且降幅不断放缓,最终最高温度保持在1 075 K左右;气膜孔不断后移的过程中,总压恢复系数不断降低。

In order to solve the problem of high wall temperature of the concave support plate in the integrated afterburner,this paper proposed a new cooling structure scheme,used three-dimensional numerical simulation to calculate the structural models in different gas film hole positions,explored the influence of film hole position on the aerodynamic and thermodynamic performance of an integrated afterburner under rated operating conditions and emphatically studied the influence of film hole position on aerothermodynamic performance indicators such as air entrainment rate,maximum wall temperature and trailing edge support plate cooling effectiveness of the concave support plate in the combustion chamber.The results show that the air entrainment rate increases linearly with the position of the gas film hole behind it,with the maximum value increasing by 124.3%relative to the minimum value,and the growth gradient gradually decreasing;the cooling effectiveness of the trailing edge support plate increases withα,with an increase of 89.3%,and the cooling effectiveness ultimately remaines around 0.35;as the position of the gas film hole continues to move backwards,the maximum wall temperature continuously decreases and the decrease slowes down,and finally the maximum temperature remaines around 1075 K;during the continuous backward movement of the gas film hole,the total pressure recovery coefficient continuously decreases.