Kamran Daneshjou - Dep. of Mech. Eng. Iran Uni. of Sci. and Tec
Roohollah Talebitooti - Dep. of Mech. Eng. Iran Uni. of Sci. and Tec
Ali Nouri - Dep. of Mech. Eng. Iran Uni. of Sci. and Tec

In this paper, analytical study is conducted on oblique plane wave incident upon a flexible orthotropic doublewalled thin cylindrical shell to understand the characteristic of sound transmission. External and internal fluid media surround the shells and there is fluid (air) in the annular space between them. A uniform flow is moving with a constant velocity in the external fluid medium. An exact solution is obtained by solving the classical shell vibration equations and acoustic wave equations simultaneously. Transmission losses obtained from numerical solution are compared with other authors. Eventually, the numerical results are used to show the effects of incident angle, Orthotropy ratio, geometrical properties, Mach number, material and fluid properties.

Wave، Transmission loss، Double-walled، Cylindrical shell، Orthotropic