Due to the viscous effects, the inviscid Kantrowitz theory can not accurately predict the self-starting Mach number of supersonic inlets. A three-layer model is used to describe the main features of the flowfield in the critical state of two-dimensional (2D) supersonic inlets during self-starting, i.e. normal shock wave/boundary layer interaction. A method for predicting the self-starting limit of two-dimensional supersonic inlets is established, which is validated by unsteady numerical simulations. Compared to the CFD results, the predicted self-starting Mach number of two-dimensional supersonic inlets is much more accurate than that of the Kantrowitz theory. The present research is of importance for both design and operation of supersonic inlets.

由于粘性效应，无粘性的坎特罗维茨理论无法准确预测超音速进气道的自启动马赫数。三层模型用于描述自启动过程中二维（2D）超音速入口临界状态下流场的主要特征，即正常冲击波/边界层相互作用。建立了二维超声速进气道自启动极限的预测方法，并通过非稳态数值模拟验证了该方法。与CFD结果相比，二维超音速进气道的预计自启动马赫数比Kantrowitz理论的精度高得多。本研究对于超音速进气口的设计和操作都具有重要意义。