Calculation of Acoustical Resonances in Irregular Cavities With Application to Noise-Induced Stress in Expansion Joints

An analytical and experimental study of the acoustic behavior of seven and nine corrugation expansion joints (bellows) used in a nuclear reactor is presented. Resonant frequencies obtained from a computer program using a matrix method are given. Experimental test results on seven corrugation expansion joints are in good agreement with the computations. It is concluded that the calculation of acoustic frequencies of expansion joints with internal sleeves can be utilized to avoid the coincidence of these frequencies with those of a mechanical or flow-induced noise nature and thus reduce the loads on expansion joint corrugations.