双通道内并联式进气道模态转换过程流动特性分析

针对双通道内并联式进气道，采用数值模拟方法研究了模态转换过程中分流板高度对抗反压能力及高/低速通道质量流量耦合时的流动特性，得到低速通道工作边界曲线，并使用动网格计算方法验证了其可靠性。结果表明：模态转换过程中随着低速通道反压增大，结尾激波会扰出低速通道并在喉道处周期性振荡，进而影响高/低速通道质量流量分配特性；当结尾激波发生周期性振荡时，反压越大，振荡频率越小，当反压进一步增大时，进气道将出现不起动；随着低速通道关闭程度增大，其抗反压能力减弱，进气道更容易发生不起动。

Study on flowfield for mode transition of over-under type inlet with double flow path

Numerical simulation model was used to study the influence of the height of splitter plate on the backpressure resistance capacity of low speed passage and the coupled aerodynamic characteristics of high/low speed passage, of which the model was validated by dynamic mesh calculation. It was found that with the increase of backpressure, the terminal shock was put out of the low speed passage and oscillated periodically in the throat. In the meantime, the frequency of oscillation decreased with adding backpressure. When the backpressure reached a specific value, the inlet failed to start. Besides, it became more difficult for inlet to work when the low speed passage was further closed as its resistance to backpressure reduced.