流体机械
流體機械
류체궤계
FLUID MACHINERY
2013年
11期
6-11
,共6页
开式叶轮%信号离析%气动噪声%时域同步平均法%旋转噪声
開式葉輪%信號離析%氣動譟聲%時域同步平均法%鏇轉譟聲
개식협륜%신호리석%기동조성%시역동보평균법%선전조성
open rotor%sign separation%aerodynamic noise%time synchronous average method%rotating noise
比较了同工况下开式叶轮气动噪声声压信号的测量结果，发现不论是在时域还是在频域上都存在较大的浮动。若采用旋转机械常用的时域同步平均法处理噪声信号，不仅需要另外安装锁相装置，还会过滤了宽频噪声信号以及使得其它非谐频信号的幅值失真。为了离析出稳定且正确的开式叶轮气动噪声信号，本文提出了一种无须安装锁相装置同时又能解决上述问题的信号处理方法，并从理论和实际运用中验证此方法的可行性。进一步分析了开式叶轮气动噪声尖峰间距特征和叶片固有频率对噪声幅值的影响。为了避免物理设备的误差，本文提出用尖峰区域下的占空比来区分旋转噪声和宽频噪声，在此基础上，计算了旋转噪声的能量在气动噪声中所占的比例和在频域下旋转噪声的能量分布。
比較瞭同工況下開式葉輪氣動譟聲聲壓信號的測量結果，髮現不論是在時域還是在頻域上都存在較大的浮動。若採用鏇轉機械常用的時域同步平均法處理譟聲信號，不僅需要另外安裝鎖相裝置，還會過濾瞭寬頻譟聲信號以及使得其它非諧頻信號的幅值失真。為瞭離析齣穩定且正確的開式葉輪氣動譟聲信號，本文提齣瞭一種無鬚安裝鎖相裝置同時又能解決上述問題的信號處理方法，併從理論和實際運用中驗證此方法的可行性。進一步分析瞭開式葉輪氣動譟聲尖峰間距特徵和葉片固有頻率對譟聲幅值的影響。為瞭避免物理設備的誤差，本文提齣用尖峰區域下的佔空比來區分鏇轉譟聲和寬頻譟聲，在此基礎上，計算瞭鏇轉譟聲的能量在氣動譟聲中所佔的比例和在頻域下鏇轉譟聲的能量分佈。
비교료동공황하개식협륜기동조성성압신호적측량결과，발현불론시재시역환시재빈역상도존재교대적부동。약채용선전궤계상용적시역동보평균법처리조성신호，불부수요령외안장쇄상장치，환회과려료관빈조성신호이급사득기타비해빈신호적폭치실진。위료리석출은정차정학적개식협륜기동조성신호，본문제출료일충무수안장쇄상장치동시우능해결상술문제적신호처리방법，병종이론화실제운용중험증차방법적가행성。진일보분석료개식협륜기동조성첨봉간거특정화협편고유빈솔대조성폭치적영향。위료피면물리설비적오차，본문제출용첨봉구역하적점공비래구분선전조성화관빈조성，재차기출상，계산료선전조성적능량재기동조성중소점적비례화재빈역하선전조성적능량분포。
In comparison with measurement results of open rotor sound pressure sign ,whether in frequency domain or in time domain,there is much fluctuation in those results .If by the method of time synchronous averaging ,not only locking phase equip-ment will be fixed addinally ,but also broadband noise sign can be filtered and the sign of harmonic frequency except times rotating frequency will be of distortion .In order to extract steady and true sign from rotor aerodynamic noise ,this paper introduces a simple and practical method without locking phase equipment , which can solve above mentioned problems .Then the method is proved to be true in theory and application analyses .What’s more, the following problems are analyzed in this paper:a distance between peeks of noise keeping a some value and how to effect noise amplitude by blade natural frequency .To avoid physical equipment error, rotating noise is able to be distinguished from broadband by computing duty ratio .On the basis, those are computed:a en-ergy ratio of rotating noise to broadband noise and energy distribution rule with noise blade passing frequency domain .
