Large area expansion can be achieved effectively by wide angle diffusers in wind tunnels, while the airflow separation may occur at the same time. In order to ensure the flow field quality, the sep—aration must be suppressed. Utilizing damp—screens with reasonable parameters is a valid method in engi—neering. With the background of 0. 6m continuum transonic wind tunnel, so as to test the engineering de—sign method of damp—screens, we verify the preliminary result by the method through the way of numerical simulation. From the calculation, by taking the scheme 3—4, loss coefficients for two screens are 1. 6 and 1. 0 respectively, the RMS value at the outlet of the wide angle diffuser will be 14. 5% ; considering the in—fluence by the environment and adjusting the two coefficients to 0. 8 and 1. 0, the RMS value will be 16. 2% . The research indicates that, the engineering design method, in addition to numerical simulations, can be effectively applied in the design of wide angle diffusers. Suppressing the airflow separation, reduc—ing the pressure loss, and improving the exit velocity uniformity can be achieved simultaneously.%采用阻尼网对大开角段内的气流分离进行控制,并合理设置其参数,是工程上有效的方法之一。为验证阻尼网工程设计方法的可靠性,以0.6m 连续式跨声速风洞为背景,通过数值模拟,对工程设计方法的初步结果进行了验证,并在此基础上结合大开角段布置环境对阻尼网参数进行了优化。由计算结果知,采用方案3—4(两层阻尼网损失系数分别为1.6 和 1.0)时,大开角段出口截面的速度均方根偏差值(RMS)为14.5%；考虑布置环境影响,调整两层阻尼网损失系数至0.8和1.0 时,RMS 值为16.2%。研究结果表明,阻尼网工程设计方法结合数值模拟可以有效地应用于大开角段整流装置的设计,达到了抑制大开角段内气流分离,降低压力损失,提高出口速度均匀性的设计目标。
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