实验流体力学
實驗流體力學
실험류체역학
JOURNAL OF EXPERIMENTS IN FLUID MECHANICS
2015年
4期
58-64
,共7页
低速风洞%声学风洞%低湍流度%信号处理%热线风速仪
低速風洞%聲學風洞%低湍流度%信號處理%熱線風速儀
저속풍동%성학풍동%저단류도%신호처리%열선풍속의
low speed wind tunnel%aeroacoustic wind tunnel%low turbulence intensity%signal process%hot wire anemometer
采用热线风速仪对5.5m×4m 低湍流航空声学风洞闭口试验段低湍流度流场进行测量,根据对干扰信号的分析,提出了高通惯性衰减滤波方法,并与一般数据处理方法进行了比较,给出了流场测量方案、方法和结果。采用功率谱方法和斯特罗哈数方法分析脉动速度信号中的干扰噪声,发现40Hz~10kHz 频谱范围内同时存在电磁干扰噪声和支架干扰噪声。比较分析了0.5Hz~5kHz 带通滤波方法、电磁噪声解耦方法和0.5Hz 高通惯性衰减滤波方法对干扰信号的滤除效果,采用0.5Hz 高通惯性衰减滤波方法获得了流场低湍流度数据,流场速度30~100m/s 的湍流度平均值小于0.05%。实验结果表明,高通惯性衰减滤波方法可以有效控制干扰信号对测量结果的影响程度,为低湍流度流场信号处理提供了一种方法。
採用熱線風速儀對5.5m×4m 低湍流航空聲學風洞閉口試驗段低湍流度流場進行測量,根據對榦擾信號的分析,提齣瞭高通慣性衰減濾波方法,併與一般數據處理方法進行瞭比較,給齣瞭流場測量方案、方法和結果。採用功率譜方法和斯特囉哈數方法分析脈動速度信號中的榦擾譟聲,髮現40Hz~10kHz 頻譜範圍內同時存在電磁榦擾譟聲和支架榦擾譟聲。比較分析瞭0.5Hz~5kHz 帶通濾波方法、電磁譟聲解耦方法和0.5Hz 高通慣性衰減濾波方法對榦擾信號的濾除效果,採用0.5Hz 高通慣性衰減濾波方法穫得瞭流場低湍流度數據,流場速度30~100m/s 的湍流度平均值小于0.05%。實驗結果錶明,高通慣性衰減濾波方法可以有效控製榦擾信號對測量結果的影響程度,為低湍流度流場信號處理提供瞭一種方法。
채용열선풍속의대5.5m×4m 저단류항공성학풍동폐구시험단저단류도류장진행측량,근거대간우신호적분석,제출료고통관성쇠감려파방법,병여일반수거처리방법진행료비교,급출료류장측량방안、방법화결과。채용공솔보방법화사특라합수방법분석맥동속도신호중적간우조성,발현40Hz~10kHz 빈보범위내동시존재전자간우조성화지가간우조성。비교분석료0.5Hz~5kHz 대통려파방법、전자조성해우방법화0.5Hz 고통관성쇠감려파방법대간우신호적려제효과,채용0.5Hz 고통관성쇠감려파방법획득료류장저단류도수거,류장속도30~100m/s 적단류도평균치소우0.05%。실험결과표명,고통관성쇠감려파방법가이유효공제간우신호대측량결과적영향정도,위저단류도류장신호처리제공료일충방법。
The 5.5m×4m low turbulence aeroacoustic wind tunnel is a low speed single-re-turn wind tunnel,capable of performing aeroacoustic,low turbulence and general low speed tests.The flow of this tunnel presents the important quality of low turbulence intensity,which needs to be measured accurately.The band pass filter and signal noise separation are the two main methods to process the low turbulence intensity data.However,the parameters of the two methods are different,and thus there is no direct comparison between their results.In this paper the low turbulence intensity of the flow field is measured in the closed test section of the 5.5m× 4m low turbulence aeroacoustic wind tunnel with the hot wire anemometry.A 0.5Hz high pass inertia attenuation filter is adopted to process the data according to the noise analysis,and the re-sults are compared with other two methods,that the 0.5Hz~5kHz band pass filter and the sig-nal noise separation.Noises in the flow field fluctuation are analyzed based on the power spec-trum and the Strouhal numbers.The electromagnetic noise and support disturbing noise are found in spectrum domain of 40Hz~10kHz.Using a 0.5Hz high pass inertia attenuation filter, the flow field turbulence intensity is measured and found to be less than 0.05% at the speed of 30~100m/s.Experimental results show that,the high pass inertia attenuation filter method can be used to control the disturbance to the results induced by noises,which is a practical method for processing the low turbulence intensity digital signal.