|
In this paper, a combination of theoretical and experimental methods to study the dynamic turbine blade vibration measurement methods and techniques. Blade vibration dynamic measurements are mainly two ways, one is contact-type strain gauge, and another non-contact discontinuous phase method, the paper focuses on the non-contact blade vibration measurement method. In theory, this paper combines the traditional non-contact blade vibration measurement method, based on the method of analysis of the basic principles of blade vibration measurements, establish the corresponding mathematical model, and combined with the actual situation improved blade vibration calculation method , in particular the calculation of the amplitude. Studies show that the proposed method can obtain a higher calculation accuracy, to reduce measurement errors. Meanwhile, the paper based on strain gauge measurements were also studied, and deduced the formula for calculating the amplitude of the blade. Bench construction, this dynamic characteristics of the blade bench design has been improved, and the bench has been transformed. The bench by the air compressor, air tank, nozzles, motors, the rotor and the corresponding piping system components, and developed a blade vibration test systems, the use of the bench can complete dynamic characteristic measurement experiment leaves and leaf rubbing Less vibration experiments. Using LabVIEW development platform, the paper developed a non-contact blade vibration measurement system and strain gauge based contact blade vibration measurement system. The measuring system includes data acquisition module, data processing module, data analysis module, data storage modules and data playback module, dynamic characteristics of the blade to achieve real-time monitoring, and can be played back through the data module for offline data analysis. In the actual blade measurement, also need blade number, the paper developed a blade numbered program that can reduce the blade pitch unevenness caused by measurement error and improve the measurement accuracy. The use of dynamic characteristics of the blade and the test bench system, this paper conducted a non-contact blade vibration measurement experiment is divided into four working conditions, and the measurement results and the theoretical calculation based on strain gauges contact measurement experimental results a comparison, made a error analysis, results show that the non-contact measurement method is feasible. Based on the above findings and other research achievements in the application of the system to detect the possibility of a site in.
|