Sound intensity measurement in strong background noise

The sound intensity measurement is a kind of acoustic measurement technology which is adaptive to the worse measurement conditions, so it is used widely for sound power measurement, sound source identification, fault diagnosis, etc. But the strong background noise affects the sound intensity measurement and causes measurement error. In this paper, we analyze the error causes of sound intensity measurement under the diesel locomotive power room when the sound power of diesel engine surface noise is measured. It is concluded that the phase mis match is the main cause why background noise influences sound intensity measurement. In the meantime, practical measurement method is given out.