High intensity acoustic testing to determine structural fatigue life and to improve reliability in nuclear reactor and aerospace structures

Abstract In this paper we review some of the techniques in which high intensity acoustic testing is used in engineering practice. These are as follows. 1. (a) In the nuclear engineering field we describe the simulation of reactor noise due to the CO 2 circulator and the use of strain gauges to obtain a response spectrum in order to predict the fatigue life of gas-cooled nuclear reactor structures where a 30 year lifespan is of paramount importance. It will be realized that, once the reactor becomes critical, the radiation hazard in the vessel will prevent any repairs from being carried out inside the reactor. Therefore it is important to ascertain the structural life before introducing the structure into a reactor. The method described here is generally used for advanced gas-cooled nuclear reactors in Britain. 2. (b) In the satellite field we discuss the simulation of the high intensity noise due to the launching rocket motors and the testing of the integrity of the satellite structure and when behaviour of the electronic control system when affected by high intensity acoustic excitation. The use of acoustic testing to improve the reliability before the launching of the satellite is also considered. 3. (c) In the aircraft and rocket field the generation of high intensity noise to simulate boundary layer pressure fluctuation or turbulence of a flying object or aircraft at various speeds is considered. This is to improve the reliability before manned flight is carried out and to eliminate premature malfunction and failures.