The general structural restrain need to be considered in the vibro-acoustic model analytically for representing the most common boundary conditions in the real engineering structure. The present work proposes to uses a vibro-acoustic model of the rectangular panel with elastic constraints for studying its responses induced by the cavity flow. The flow fluctuations  in the rectangular cavity is analyzed with different flow conditions by computational fluid dynamics（CFD）method and transferred to surface loads on the bottom panel in the cavity firstly. The vibro-acoustic model of the panel backed with cavity is established by considering the general structural restrains .Then, the vibrational response and radiated sound power of the panel are calculated by substituting the loads into the vibro-acoustic models. Finally, the effects of the boundary stiffness and flow velocity on the vibrational response and radiated noise of the panel are studied to reveal the response principles of the panel with elastic restraints induced by the cavity flow.

vibro-acoustic model; cavity flow; elastic constraints; vibration energy; radiated sound power