英语翻译To provide a contour that vividly shows the footprint of the air- foil noise,the background noise and jet speed were rst measured simultaneously as the ow speed was gradually reduced from its maximum value.This procedure was repeated with

英语翻译To provide a contour that vividly shows the footprint of the air- foil noise,the background noise and jet speed were rst measured simultaneously as the ow speed was gradually reduced from its maximum value.This procedure was repeated with
英语翻译
To provide a contour that vividly shows the footprint of the air- foil noise,the background noise and jet speed were rst measured simultaneously as the ow speed was gradually reduced from its maximum value.This procedure was repeated with the airfoil in- stalled at zero angle of attack (with sandpaper removed).Fig.14a and b show,respectively,the contours of the sound pressure levels plotted as a colour map against frequency and ow speed without and with the airfoil.The resolution of the jet speeds presented in the gure is within 0.3-0.5 m/s.While a low overall background noise level is observed (Fig.14a),a distinct broadband-‘‘hump” can be found for the case of trailing edge self-noise as well as the low frequency noise caused by the ow impingement to the airfoil leading edge at higher jet speeds (both indicated in Fig.14b).When the results were compared with the Brooks et al.’s prediction scheme,although not shown here,both agree extremely well.

英语翻译To provide a contour that vividly shows the footprint of the air- foil noise,the background noise and jet speed were rst measured simultaneously as the ow speed was gradually reduced from its maximum value.This procedure was repeated with
To provide a contour that vividly shows the footprint of the air-foil noise, the background noise and jet speed were rst measured simultaneously as the ow speed was gradually reduced from its maximum value. 为了提供生动显示机翼噪声的足迹的轮廓,随着（OW）速度从其最高值逐步降低,对背景噪声和射流速度同时进行了（rst）测量.This procedure was repeated with the airfoil in- stalled at zero angle of attack (with sandpaper removed). 这一程序在机翼以零迎角下（砂纸去除）安装时重复.Fig. 14a and b show, respectively, the contours of the sound pressure levels plotted as a colour map against frequency and ow speed without and with the airfoil. 图14a和b分别示出了有机翼和没有机翼时,声压水平随频率和（OW）速度绘制的轮廓.The resolution of the jet speeds presented in the gure is within 0.3-0.5 m/s. 图中示出的射流速度的分辨率在0.3－0.5 m/s之内.While a low overall background noise level is observed (Fig. 14a), a distinct broadband-‘‘hump” can be found for the case of trailing edge self-noise as well as the low frequency noise caused by the ow impingement to the airfoil leading edge at higher jet speeds (both indicated in Fig. 14b). 尽管观察到了低的总背景噪声水平（图14a）,但在拖尾边缘自噪声的情况下,可以发现一明显的宽带“峰”,以及在较高射流速度下对机翼前缘的（OW）冲击引起的低频噪声（这两者都在图14b中表示了出来）.When the results were compared with the Brooks et al.’s prediction scheme, although not shown here, both agree extremely well. 当这些结果与Brooks等人的预测方案比较时,虽然这里没有表示出来,但两者的一致性都很好.

提供一个轮廓,生动地展示了空中的足迹,烘托噪声、背景噪声和喷气速度rst同时测量的速度逐渐雪从它的最大值。这个过程中再次在0 -翼角(用砂纸移除)。图显示,和b。14a的规定,在各自的声压等级轮廓绘制颜色与地图攻击频率和现在的速度,而不与翼型。这项决议的喷气机的速度之间的关系,提出了在gure 0.3 - 0.5米内付款的汇票。虽然低整体背景噪声水平是观察(图)、鲜明。14a的规定,“驼峰”宽带可...

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提供一个轮廓,生动地展示了空中的足迹,烘托噪声、背景噪声和喷气速度rst同时测量的速度逐渐雪从它的最大值。这个过程中再次在0 -翼角(用砂纸移除)。图显示,和b。14a的规定,在各自的声压等级轮廓绘制颜色与地图攻击频率和现在的速度,而不与翼型。这项决议的喷气机的速度之间的关系,提出了在gure 0.3 - 0.5米内付款的汇票。虽然低整体背景噪声水平是观察(图)、鲜明。14a的规定,“驼峰”宽带可以发现的情况下self-noise以及低频噪声的雪,造成冲击的翼型喷气速度更高领先优势,指出在图(两个)。14b。当这个结果进行了比较和布鲁克斯等的预报方案,尽管没有显示,都非常好。

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To provide a contour that vividly shows the footprint of the air- foil noise, the background noise and jet speed were rst measured simultaneously as the ow speed was gradually reduced from its maximum...

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To provide a contour that vividly shows the footprint of the air- foil noise, the background noise and jet speed were rst measured simultaneously as the ow speed was gradually reduced from its maximum value. This procedure was repeated with the airfoil in- stalled at zero angle of attack (with sandpaper removed). Fig. 14a and b show, respectively, the contours of the sound pressure levels plotted as a colour map against frequency and ow speed without and with the airfoil. The resolution of the jet speeds presented in the gure is within 0.3-0.5 m/s. While a low overall background noise level is observed (Fig. 14a), a distinct broadband-‘‘hump” can be found for the case of trailing edge self-noise as well as the low frequency noise caused by the ow impingement to the airfoil leading edge at higher jet speeds (both indicated in Fig. 14b). When the results were compared with the Brooks et al.’s prediction scheme, although not shown here, both agree extremely well.
为了提供一个轮廓这生动地表明了足迹的空调箔噪音，背景噪声和喷射速度为第一衡量的同时怎么速度逐渐减少其最大的价值。这一程序是重复的翼型在停滞在零攻角（与砂纸删除） 。图。 14A条和B分别显示的轮廓声压级绘制地图的颜色怎么对频率和速度，并与翼型。该决议的喷射速度中提出的gure是在0.3-0.5米/秒虽然总体背景噪音低一级的观察（图14A条） ，一个独特的宽带''hump “可以找到的案件后缘自噪声，以及低频噪声所造成的冲击，以现在的翼型领先优势在更高的喷射速度（都表示在图。 14B条） 。当结果进行了比较与布鲁克斯等人。的预测计划，虽然没有表现出在这里，都一致认为非常好。

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