抄録
The particle velocity of excitation source is necessary to measure the transfer function of the sound field. Therefore we connect acoustic duct to the sound field and use 2-microphone measure technique that calculates the particle velocity of boundary by two points of sound pressure. Precondition of 2-microphone measure technique is that plane wave is transmitted in acoustic duct. However, the situation that the sound pressure on the boundary is not plane wave is thought about depending on a state of the sound pressure distribution of the sound field. In this study, we analyzed a connected sound field model. When node of the particle velocity emerge on boundary, we cannot be obtained a correct result by experiment. Calculated result agreed with experiment and we showed a condition particle velocity on boundary is not plane wave.
