2マイクロホン法を用いた伝達関数の推定によるコージェネレーションシステムの音源分離

摘要

コージェネレーションシステム（以下CGS）は1種類rnの燃料から，電気や熱等2種類以上のエネルギーを同rn時かつ連続的に得るシステムである．したがって，熱rn効率が高く経済性に優れている．この特徴を活かすべrnく，現在では中規模，大規模建築物等に導入されていrnる．%This paper presents Frequency Response Function (FRF) estimation with the two-microphone method and its application for noise source separation. The cogeneration system radiates noise caused by its gas engine, which is power plant installed in the enclosure. Noise radiated from the enclosure consists of structure- and air-borne noise. Therefore, to reduce the noise radiated from the cogeneration system, it is significant to investigate the contribution of each noise source. In this paper, by using FRF which reference was volume velocity, contributions of noise sources in the cogeneration system were identified. Volume velocity source consists of a speaker, a tube and two probe microphones. FRF was estimated from the outputs of two microphones inside tube and that of a microphone at a response point. At first, the accuracy of the proposed method was investigated by the comparison between the test and the simulation by boundary element method. Next, the effectiveness of this method was confirmed by the noise source separation of the enclosure that includes an electro-magnetic shaker and the volume velocity source. Finally, noise source separation of cogeneration system was performed. As a result, a good agreement was observed between the measured results and the identified ones.