Research Of Flow Characteristic And Noisecharacteristic In Cone Throttle Valve

The Cone throttle valve is widely used in the main circuit of hydraulic system, the pilot stage of hydraulic valve and the regulator of hydraulic pump because of its advantages such as the simple structure, good sealing, high sensitivity and resistance to pollution. Depending on the numerous structures of throttling groove, the characteristic of flow, pressure and cavitation noise caused in the throttle valve were not identical, thus the control features of the hydraulic system were produced different, and also with different degree of cavitation noise. These problems not only increase the control difficulty of the hydraulic system, but also the cavitation noise pollution, which affect the physical and mental health of workers. Further study on the characteristics of flow and cavitation noise in the cone throttle valve has an important theoretical significance and practical value.In this thesis, the cone throttle valves with rectangle, u-shaped and triangular throttling groove were selected as the objects, then simulation about flow field inside the throttle valves were conducted based on the fluid-structure interaction modules in ADINA, also the test bench about the characteristics of flow and noise in the hydraulic valve was carried out to study the characteristics of flow and cavitation noise in different throttling groove of throttle valves.Firstly, the research status and existing problems about characteristics of flow and cavitation in the hydraulic valve were summarized; and the theory about fluid mechanics, cavitation theory and acoustic theory were simply introduced.Secondly, by using Solid Works and the pre-processing of ADINA, the simulation models of rectangle, u-shaped and triangle(53°, 45°, 60°) throttling groove were established. Through fluid-structure interaction module, the pressure and velocity distribution of different throttle valves were obtained. The characteristics of the inner flow field in the cone throttle valves were showed in the form of plot pictures.Lastly, based on the different structure characteristics of throttling groove, the flow area computation formulas of the cone throttle valves were deduced, and the calculation programs were generated using MATLAB software. In addition, the test bench about the characteristics of flow and cavitation noise in the cone throttle valve was set up, and the experimental data about pressure, flow and noise were obtained. Then, combined with flow area computation programs, the flow coefficients in different structure of the throttle valves were obtained. At the same time, the cavitation noise in the cone throttle valve was analyzed from the perspective of noise acoustic level and noise frequency.