跨声速风洞斜孔壁非线性流动试验

为分析跨声速风洞斜孔壁近壁区域的流动特性，评估气流偏角-压力系数的非线性关联，在0.6 m跨超声速风洞中开展了基于七孔探针的流动特性测量试验。通过气流偏角和压力系数分布分析了斜孔壁流动的差阻特性，以及马赫数、模型升力对斜孔壁流动的影响，最后基于试验结果发展了计算斜孔壁特性参数的微分法，并与经验方法结果进行对比。结果表明，斜孔壁流动呈现出明显的差阻性和非线性，在负压差范围内，近壁流动仍以出流为主；高亚声速时，空风洞模型区孔壁流动特性趋于实壁；安装模型后，随着升力的增大，升力面对应的孔壁区域流动向入流发展，孔壁流动特性趋于开口边界。

Experiment on nonlinear flow near perforated wall with slanted holes in transonic wind tunnel

To analyze the characteristics of the flow near the transonic perforated wall with slanted holes and to evaluate the nonlinear relationship of flow angle and pressure coefficient, an experiment on flow characteristics is conducted in the 0.6 m transonic and supersonic wind tunnel using seven-hole probe. The differential resistance of flow in perforated wall region, as well as the influence of Mach number and model lift are analyzed using distributions of flow angle and pressure coefficient. Finally, based on the experimental results, a differential method for calculating the porosity parameter of perforated wall with slanted holes is developed and compared with the classical methods. The results indicate that the flow near perforated wall with slanted holes has significant differential resistance and nonlinearity. In the range of negative pressure difference, the flow near the wall is still dominated by outflow. At high subsonic speeds, the perforated wall flow characteristics tend to be solid in the model area for the empty tunnel condition. With the model installed, perforated wall flow tends to enhance the inflow as the lift increases in the opposite area of lift surface, and the perforated wall flow characteristics tend to be open boundaries.