Research On Aerodynamic Noise And Flow-Induced Vibration Of Orifice Sleeve Control Valve

Orifice sleeve control valves are widely used in thermal power plants and nuclear power plants.They play an important role in the safety and stability of the entire power plant operation.With the development of national ultra-supercritical thermal power plants and third-generation nuclear power plants,the domestic traditional sleeve valve can no longer meet the requirements for smooth operation under special working conditions such as high temperature,high pressure and high flow rate.It is of great significance to investigate the noise and vibration characteristics of the sleeve structure parameters of the sleeve valve,optimize and innovate the structure of the guide sleeve structure,and break the monopoly of foreign technology and products.With the support of the Zhejiang Province Key R&D Project "Research on Key Technology of High-parameter Special Control Valve for Third Generation Nuclear Power Plant"(2021C01021)and National Natural Science Foundation of Chinese general project " Research on Design Theory,Method and Key Technology of Large-Capacity Temperature-Reducing and Pressure-Reducing Device under Extreme Working Conditions"(51875514),this article carried out the optimization research of noise and vibration reduction in the sleeve of the sleeve valve.Through the method of combining numerical simulation and experimental measurement,the influence of the structure parameters of the sleeve valve on the flow rate characteristics,flow characteristics,noise characteristics and vibration characteristics is studied.Optimized design schemes of sleeve structure parameters for reducing flow-induced vibration and aerodynamic noise are proposed.The main research contents and results are:(1)A set of modular sleeve flow characteristic measurement device was built.The change law of the inherent flow rate characteristics under different sleeve structure parameters were studied through experiments,and the reliability of the numerical simulation method was verified.Then,the influence of sleeve structure parameters on flow rate characteristics was studied,including the shape of the inner valve plug of the sleeve and the diameter ratio between inner holes and outer holes,corresponding flow characteristic curves and design method of holes diameters in the sleeve based on the flow coefficient were obtained.(2)For horizontal sleeve valves and angle sleeve valves,by establishing a steady-state numerical model of compressible superheated steam,the effects of sleeve structure parameters on flow characteristics of sleeve valves were explored at the fixed opening,including the pressure field,the velocity field and the temperature field.Results showed that increasing the sleeve gap could increase the pressure drop of the outer sleeve,reduce vortexes,reduce the turbulence intensity and the maximum Mach number,and make the steam flow state relatively stable;changing the sleeve thickness has little effect on flow characteristics.The larger the relative angle of the orifices between the sleeves,the better the pressure drop effect at the sleeves,the lower the degree of turbulence,and the higher the stability of the steam flow state.(3)As for aerodynamic noise characteristics of the sleeve valve,the effects of the sleeve thickness and the sleeve gap on the noise source,noise directivity and noise spectrum characteristics of the valve under different openings were analyzed.Results showed that increasing the sleeve gap would increase the unevenness of APL distribution in the valve cavity,reduce the unevenness of APL distribution inside the sleeve,and reduce OSPL of the monitoring point,whose noise reduction amplitude increased with the decrease of the opening.Increasing the sleeve thickness had the opposite effects in APL distribution,and OSPL of the monitoring point decreased slightly.The sleeve structure with sleeve thickness of 2 mm and sleeve gap of 7 mm had a better noise reduction effect.Under the normal operation condition opening and the minimum operation condition opening,the fitting formula of aerodynamic noise prediction about the sleeve gap and the sleeve thickness was obtained.A dimensionless number-inter-thickness number Gt related to the structure parameters of the sleeve was proposed,which could quickly compare the aerodynamic noise level of different sleeve thickness and sleeve gap combinations in the same sleeve valve.(4)As for flow-induced vibration characteristics of the sleeve valve,using one-way fluid-solid coupling and two-way fluid-solid coupling methods respectively,the pre-stress modals of sleeve valves under different openings were analyzed,and the effects of the orifice structure parameters on the flow-induced vibration characteristics of the maximum vibration point under the maximum vibration opening were analyzed.Results showed that the smaller the opening,the greater the total vibration level of the valve stem,and the maximum vibration point was the center of the valve stem top.Without affecting the flow capacity of the sleeve valve,the single sleeve adopted the horizontal short holes and the porous structure to help improve the vibration damping effect.The more sleeves there were,the improvement of the damping effect was not obvious.The innovative design of vibration reduction in the sleeve valve could reduce the total vibration level of the valve stem in all directions without affecting the flow capacity of the sleeve valve.