An acoustic intensity vector measurement system for three dimensional by the method of right angle four microphones and its application

摘要

It is well known that, in the conventional two-microphone measurement with a phase mismatch between microphones and channels, a so-called bias error appears and the measurement error increase as the frequency becomes lower. In this paper, from the consideration on the 2-microphone technique, the acoustic intensity vector measuring technique based on the configuration of the right angle 4-microphones is proposed. First, the theoretical background of the right angle 4-microphones is discussed, and then the technique based on the theory is validated experimentally. From the results, it can be said that the acoustic intensity measurement system is the effectiveness for supervision of the road traffic noise.