並列タイトル等Acoustics and Performance of High-Speed, Unequally Spaced Fan Rotors
タイトル(掲載誌)航空宇宙技術研究所報告 = Technical Report of National Aerospace Laboratory TR-526
一般注記This paper describes an experimental measurement of the effects of uneven blade spacing on the acoustic and aero-thermodynamic characteristics of high-speed, high-pressure-ratio fan rotors at two selected spacing configurations. A test rig, consisting of inlet guide vanes and transonic rotor blades, was employed to explore the redistribution of harmonic sound energy into a series of multiple tones of lower sound pressure level. The measured data indicated that a 10% modulated rotor exhibited a six to eight decibel decrease in the sound pressure level as compared with the original first blade passage frequency harmonic. Disadvantages in aerodynamic performance resulting from spacing modulation were not so unfavourable for 10% modulated blades. However, with 5% modulated blades, serious deterioration in aerodynamic performance was observed particularly near the blade tip section, which produced an unfavourable acoustic signature. A calculation method, assuming a pulse event for each blade sound pressure, provided agreeable results with the measured data.
資料番号: NALTR0526000
レポート番号: NAL TR-526
一次資料へのリンクURLhttps://jaxa.repo.nii.ac.jp/?action=repository_action_common_download&item_id=44780&item_no=1&attribute_id=31&file_no=1
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース(IRDB)(機関リポジトリ)
提供元機関・データベース宇宙航空研究開発機構 : 宇宙航空研究開発機構リポジトリ