超声速物面振动气动力的非线性效应研究

This paper studies the major source of aerodynamic nonlinearity for surface vibration in supersonic flow and analyses the main factors affecting the nonlinear utility. Firstly, a piston theory considering shock wave and expansion wave (SE-PT) is established. Through comparing the calculated results from the SE-PT with the results from conventional piston theory and Euler equations, the physical significance of the high-order term in the piston theory is clear. We study the application of the piston theory to panel vibrations in single and double side air flow and analyze the aerodynamic nonlinear utilities. The method how the vibration frequency influences the aerodynamic nonlinearity is further explored, and the application scope of the linear piston theory is redefined. The major conclusions are given as follows: (1) the aerodynamic nonlinearity comes from shock and expansion waves for the supersonic surface vibration, which can be strengthened by the symmetry of panel modal; (2) the nonlinearity utility is apparently weakened in double-side supersonic flow; (3) the physical significance of the high-order term in the piston theory is nonlinear utility coming from shock and expansion waves, which is firstly weakened and then strengthened with the increase of vibration frequency.