Dynamic Pressure Measurement System on Rotor Blade Surface Based on Phase Locking Method

Abstract

The invention relates to a rotor blade surface dynamic pressure measuring method and system based on a phase locking method. The measuring system designed by the measuring method comprises a high-sensitivity photoelectric sensor, a micro dynamic pressure sensor, an infrared trigger, a data recorder fixed to a rotating shaft, a data acquisition card and other devices. The rotor blade surface dynamic pressure measuring method and system based on the phase locking method can overcome the defects of an existing device, sampling frequency of the designed system is only related to sampling frequencyof the sensor and the data recorder, and the limitation on the sampling frequency caused by a data transmission mode is avoided. As a data transmission line is adopted for data transmission, noise interference can be avoided to the greatest extent, and the accuracy of acquisition data can be ensured; and meanwhile, the instability of rotating speed is considered, the phase locking method is adopted, so that the rotor surface dynamic pressure is accurately recorded, a rotor blade rotating phase is recorded in an absolute coordinate system, and the pressure information of the blade surface at acertain phase is accurately extracted.

Description

technical field [0001] The invention relates to an experimental method for measuring dynamic pressure on the rotor blade surface of a rotary machine, and more specifically, the method is based on a phase locking method to realize the measurement of the dynamic pressure on the rotor blade surface. Background technique [0002] As an important energy conversion and power transmission device, impeller machinery is widely used in various fields of the national economy, from electric fans in daily life to various forms of blowers and water pumps used in industrial production, and in the aerospace field. Compressors, turbines, etc. all belong to the category of turbomachinery. The flow field inside the turbomachinery is essentially a complex three-dimensional, viscous, unsteady flow field, and the state of any point in space changes with time. The pressure distribution on the rotor blade surface reflects many details of the flow field, and its dynamic changes often produce more p...

AI Technical Summary

Problems solved by technology

Moreover, most technologies are difficult to solve the problems of signal distortion and electromagnetic interference in the process of signal transmission and conversion. Therefore, they only stay at the stage of theoretical research and are difficult to apply to engineering practice.

At the same time, since the rotational speed of the rotating machinery cannot be kept absolutely stable, the relationship between the rotor blade phase and time cannot be kept absolutely periodic, and the collected data often cannot accurately correspond to the rotor phase.

However, domestic dynamic pressure measurement systems seldom take into account the problem of speed instability

This problem can be solved with the help of the phase locking method. The current phase locking method used in China is often based on the relative coordinate system, and it is still unable to obtain the precise correspondence between the collected data and the absolute coordinate system, and cannot accurately record the phase and the relative coordinate system. corresponding pressure

This has an impact on the results of subsequent data analysis and processing, resulting in the inability to accurately extract the data collected by the sensor at a certain phase of the blade

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