Propagation of AE Wave in the Air that was Occurred in a Window Frame

摘要

Window frames of an excellent hotel were warmed up by sunshine in the summer. Thernwindow frames were stressed by the thermal stress, and frames squeaked because of thernsudden changes in temperature. This phenomenon is called one of Acoustic Emissionrn(AE). Many guests could hear those squeaks, but they could not find out thernhypocenters. So, the acoustic emissions and the squeaks were measured by an AErninstrument and by sound-level meters.rnThe hypocenters which were occurred in the window frames were decided by the AErninstrument. But it was very difficult to decide them by the sound-level metersrnbecause of the difference of the propagation velocity of P-wave in the window framesrnand in the air.