叶尖定时联合相位切线的旋转叶片阻尼测定

发布时间：2018-02-15 10:22

本文关键词： 高速旋转叶片叶尖定时阻尼测定振动响应　出处：《推进技术》2017年08期 　论文类型：期刊论文

【摘要】：针对高速旋转叶片阻尼识别难的问题,提出了一种利用叶尖定时技术获取叶片振动响应,进而由相频曲线在共振点的切线斜率求取模态阻尼比的新方法——相位切线斜率法。对原始相频数据进行拉格朗日插值后,再由中心差分得到共振点处的切线斜率。介绍了叶尖定时理论,阐述了相位切线斜率法原理,并将其应用于仿真阻尼与实际高速旋转离心叶片阻尼的识别当中。结果表明,相位切线斜率法在满足频率比间隔足够小(例如1×10-6)时,误差可达到1×10-4%数量级,远小于半功率带宽法的最大误差53.68%。在旋转叶片模态阻尼识别中,相位切线斜率法、半功率带宽法和Hood软件识别结果存在数量级上的可比性;不同叶片的模态阻尼比呈现一定的分散性,但总体落在8.0×10-4~1.2×10-3的范围内。由此说明,相位切线斜率法识别结果可靠可信。
[Abstract]:Aiming at the difficulty of identifying the damping of high speed rotating blades, a method of obtaining blade vibration response by using tip timing technique is proposed. Then the phase tangent slope method is a new method to obtain the damping ratio from the tangent slope of the phase frequency curve at the common vibration point. The original phase frequency data are interpolated by Lagrange interpolation. Then the tangent slope at the common vibration point is obtained by central difference. The tip timing theory is introduced, and the principle of phase tangent slope method is expounded. It is applied to the identification of simulation damping and actual high-speed centrifugal blade damping. The results show that, The error of phase tangent slope method can reach 1 脳 10 ~ (-4)% when the frequency ratio is small enough (for example, 1 脳 10 ~ (-6)), which is much smaller than the maximum error of half power bandwidth method (53.68). The results of half-power bandwidth method and Hood software are comparable on the order of magnitude, and the modal damping ratio of different blades shows a certain dispersion, but falls within the range of 8.0 脳 10 ~ (-4) or 1.2 脳 10 ~ (-3). It shows that the recognition results of phase tangent slope method are reliable and reliable.
【作者单位】：中国航空动力机械研究所航空发动机振动技术航空科技重点实验室;
【基金】：航空科学基金项目(2014ZD08007)
【分类号】：TH113.1

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