The ramjet/scramjet engines require the control-oriented model to predict the inlet flow field in less than a few seconds. However, it is challenging for these kinds of inlets which utilize curved shock waves to compress the air flow. In this paper, a reduced-order model based on the computational fluid dynamics, the proper orthogonal decomposition theory, and the radial basis function interpolation method is developed. After that, the curved shock waves dominated flow fields of a ramjet inlet under different angles of attack and free stream Mach numbers are predicted with this reduced-order model and compared to the full order computational fluid dynamics solutions. The results show that this reduced-order model can successfully predict the curved shock waves, the curved shock wave/boundary layer interactions, and the shock trains caused by a back pressure with high accuracies. The consumed time is only 0.11 s. The performance parameters are also predicted with the relative errors no more than 2%.

冲压喷气发动机/超燃冲压发动机需要面向控制的模型，以在不到几秒钟的时间内预测入口流场。然而，对于利用弯曲的冲击波来压缩空气流的这些类型的入口来说是具有挑战性的。本文基于计算流体动力学，适当的正交分解理论和径向基函数插值方法，建立了降阶模型。此后，使用该降阶模型预测在不同迎角和自由流马赫数下冲压喷气机入口处的弯曲冲击波流场，并将其与全阶计算流体动力学解决方案进行比较。结果表明，该降阶模型可以成功预测弯曲冲击波，弯曲冲击波/边界层的相互作用，以及由高精度的反压力引起的冲击波。消耗的时间仅为0.11 s。还预测了性能参数，相对误差不超过2％。