%0 Journal Article
%T 基于触发脉冲的涡轮机械叶尖间隙监测方法<br>Investigation on the Blade Tip Clearance Monitoring of Turbomachinery Based on the Pulse-Trigger Method
%A 王维民
%A 邵化金
%A 陈立芳
%A 屈维
%J 振动.测试与诊断
%D 2017
%R 10.16450/j.cnki.issn.1004-6801.2017.25
%X 针对电涡流传感器在进行叶尖监测时因带宽不足导致的欠采样问题，提出了一种基于触发脉冲的叶片健康监测方法。通过对传感器在不同叶尖相对位置的灵敏度进行标定，获得传感器灵敏度与传感器探头到叶尖的距离及与叶尖重合度的函数表达式。在监测过程中，将叶尖间隙与叶尖计时数据相融合，通过叶尖计时的方法得到在各个数据点的采集时刻，计算传感器探头与叶片的重合度，结合标定得到的函数表达式，可分析得出各个数据点对应的叶尖间隙值，并通过搭建的叶尖间隙监测实验台进行了实验验证。结果表明，较于峰值定位法，所提出的触发脉冲法有效地解决了因电涡流传感器带宽限制引起的欠采样问题，改善了高线速度下叶尖间隙的测量准确性，为基于电涡流传感器的叶尖间隙主动控制及叶片振动监测提供基础。<br>Blade tip clearance (BTC) and blade vibration measuring are the principal tools for blade health monitoring (BHM), which can improve the efficiency and reliability of turbomachinery. In this paper, a BTC monitoring method based on pulse-trigger of eddy current sensor (ECS) is presented, in the light of the sub-Nyquist sampling caused by the limit of narrow-band, especially for the high linear velocity. The proposed method optimizes the static radial and circumferential calibration technology to obtain the sensitivity of ECS in the different relative location against the tip of blade and to obtain the function of impedance of the ECS that relates to the distance and the contact ratio of the ECS from the tip of blade. Combining blade tip timing (BTT) technology into BTC monitoring, this method calculated the contact ratio of the ECS from the blade, in order to obtain the accurate clearance depends on the function obtained before for all sampling points. Also, a BTC monitoring rig is established to validate the feasibility of this method under varying rotating speed. The results show that this method can solve the problem of sub Nyquist sampling caused by the limit of narrow band for ECS in the condition of high linear velocity. Compared with the location obtained by peak picking, the method presented in this paper can significantly improve the accuracy of BTC monitoring. This research can provide the basis for BTC active control and BHM based on ECS.
%K 电涡流传感器&lt
%K br&gt
%K turbine blades
%K blade tip clearance(BTC) monitoring
%K pulse-trigger
%K optimize static calibration technology
%K eddy current sensor (ECS)
%U http://zdcs.nuaa.edu.cn/ch/reader/view_abstract.aspx?file_no=201703025&flag=1