The isentropic motion of a perfect ideal gas on a constant homogeneous supersonic background is considered. A two-dimensional stationary potential problem of gas dynamics is solved to study the interaction of three traveling waves whose amplitudes and phases are slowly varying in the direction of the background flow in the case when the sum of “harmonic” phases is exactly equal to zero. The equations of amplitude and phase variation are derived and their solutions are analyzed analytically. The question of what boundary conditions should be satisfied is discussed.

中文翻译：

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二维二维气体动力学平稳问题中的三波共振

考虑了理想理想气体在恒定均质超音速背景下的等熵运动。解决了一个二维的气体动力学平稳势问题，研究了三个行波的相互作用，这些行波的振幅和相位在背景流方向上缓慢变化，而“谐波”相位之和恰好等于零。推导了振幅和相位变化方程，并对其解析进行了分析。讨论了应满足哪些边界条件的问题。