kirchhoff formula การใช้

• The comparison showed that : ( l ) farassat 1a formula is the simplest one and work well for the subsonic rotor . ( 2 ) both kirchhoff formula and k - fwh formula can predict the nonlinear noise generated by transonic rotor ; ( 3 ) when the surface is not positioned in the linear region , kirchhoff approach for rotating integration surface could lead to substantial error , but k - fwh formula can still work well