Cylindrical Shell Band Vibration And Sound Radiation Characteristics

Noise radiated from underwater aircraft is an increasingly very important ocean environmental pollution at present. The shell vibration drove by the inner engine, when coupled with the liquid medium, which will not only affect the ocean environment but also affect the performance of the vessels badly. Finite cylindrical shells with stiffeners are just major structures of cabin on the submerged or underwater vehicles. Thus it has very important theoretic value and practicality to research sound-vibration characteristic of the finite cylindrical shell with stiffener.On the basis of the sound-vibration radiation of the simple structure, numerical analysis of vibration and sound radiation efficiency about a few kinds of the finite length cylindrical shells in the fluid are disused. The FEM and BEM analysis matrix are built for the complicated cylindrical shell with stiffen ribs. By use of the software ANSYS and SYSNOISE, the response of the sound and vibration radiation of shells are computed, the influence of the shell vibration drove by ribs are analyzed.In order to compute the response of the vibration radiation of the shells at the critical frequency, the SEA methods are adopted to build the cylindrical shells in the fluid, which is useful to obtain the rule of noise radiation in high frequency.As can be seen from the above conclusions, good techniques are provided to compute the sound-vibration radiation in the fluid in the whole frequencies, which provide the basis for studying the sound-vibration radiation of the complicated structures and are of great meaning to control the radiation noise of the vessels.