고차고해상도 수치기법을 이용한 초음속 제트 screech tone의 axisymmetric mode 해석

NUMERICAL ANALYSIS OF AXISYMMETIC SCREECH TONE FROM SUPERSONIC JET USING HIGH-ORDER HIGH-RESOLUTION COMPACT SCHEME

The screech tone of an underexpanded jet is numerically calculated without any specific modeling for the screech tone itself. A fourth-order optimized compact scheme and fourth-order Runge-Kutta method are used to solve the 2D axisymmetric Euler equation. The Fourier transform of pressure signal at upstream shows the directivity pattern of the screech tone very clearly. Pressure signal is shown to observe the generation of the screech tone. Most importantly, we can simulate the axisymmetric mode change of the screech tone very precisely with the proposed method. It can be concluded that the basic phenomenon of the screech tone including its frequency can be calculated and its mode change can be simulated with inviscid Euler equations.