抄録
Acoustically induced vibration in piping systems can cause severe failures -acoustic fatigue- of the piping structure in the process plant. To prevent the acoustic fatigue, the design criteria relating acoustic power level at noise sources to geometry parameter based on the ratio of the piping diameter to the thickness has been applied in some design specifications for the process plant of major oil companies. However, the evaluation method and the detailed mechanism of these phenomena are still under study. The numerical investigation using sound-structure interaction analysis has been done to give the dominant factors which cause the high stresses in the piping structure. The result shows that the coincidence of loading frequency and structural natural frequency plays an important role in acoustically induced vibrations. New geometry parameter representing the structural natural frequency was introduced as one of the reasonable approaches to make a screening diagram for prevention of acoustic fatigue for the plant design.
