@article{oai:nagasaki-u.repo.nii.ac.jp:00025660, author = {児玉, 好雄 and 林, 秀千人 and 淵上, 真一郎 and 三村, 雄次郎 and 脇山, 卓哉}, issue = {54}, journal = {長崎大学工学部研究報告, Reports of the Faculty of Engineering, Nagasaki University}, month = {Jan}, note = {The discrete frequency noise generated from a tubular centrifugal fan was investigated in relation to the resonance with the inlet duct, the interaction with the stator and the inlet distortion flow experimentally. The following results an obtains. It was shown that the length of the inlet duct makes a great influence to the resonance of the discrete frequency noise. At the tubular fans, the wake flow from the rotor diffuses rapidly, then the interaction of it with the stators done not occur. By the way there is the large distortion flow inlet distortion flow and the rotor makes the discrete frequency noise, the interaction noise. That is, it was cleared that the discrete frequency noise is not cause by the interaction with the stators and rotor, but by the inlet distortion flow and rotor. And it was indicated the method to reduce the level of the inlet noise by using the honeycomb in the bellmouth. The noise level can be reduced about 9 dB., 長崎大学工学部研究報告 Vol.30(54) p.9-15, 2000}, pages = {9--15}, title = {チューブラー遠心送風機の入口偏流による騒音への影響}, volume = {30}, year = {2000} }