Aerodynamic Noise And Digital Twin Modeling Study Of Multi-Stage Sleeve Control Valve

Control valve is the most widely used control equipment in thermal power unit control unit,with the booming development of thermal power units in China,the working conditions of control valve are increasingly improved,with the proposed clean energy,the noise problem becomes an important optimization index of control valve,and the pneumatic noise has higher sound power and more harmful compared to fluid noise.Therefore,in this paper,a new sleeve control valve with built-in multistage throttling element is proposed,and a digital twin modeling UI interface of multi-stage sleeve control valve is established and the fidelity of the digital twin modeling is verified with it as the research object.The flow characteristics,noise characteristics,and circumferential distribution of pneumatic noise are studied with the verified model.In this paper,the multi-stage sleeve control valve structure is optimized according to the causes of pneumatic noise generation,and the noise before and after optimization is compared.The main work is as follows:1.The importance of control valves in thermal power units and the gradual difficulty of domestic control valves to meet the operational requirements with the improvement of working conditions and requirements were analyzed,among which the noise problem is especially prominent.According to the national "Smart Manufacturing 2025",digital twin technology should come out,combined with the status of domestic and international research on control valves and digital twin,the research significance of pneumatic noise of control valves and the necessity of digital twin of specific components were proposed.2.The structure and operating principle of the multi-stage sleeve control valve are introduced systematically,the control equations and the related turbulence model and noise model required for the subsequent simulation are introduced,and the differential form of the control equations is analyzed and simplified in combination with the simulation of the specific operating conditions of the control valve.The theoretical basis is laid for the simulation and analysis of the flow field acoustic field of multi-stage sleeve control valve.3.To introduce the concept of digital twin modeling and the relationship between the digital twin modeling and other components in the digital twin mapping model,the digital modeling twin environment is built according to the experimental conditions of the multi-stage sleeve control valve,the virtual model of the multistage sleeve control valve is established,the monitoring panel and control components are designed,and integrated into the UI interface of the digital twin modeling.The flow channel model is meshed and mesh-independent checked,and the boundary conditions of the fluid simulation are determined according to the actual working conditions.The simulation parameters of the control valve are proposed through the fluid simulation and brought into the mathematical model of the flow coefficient to obtain the flow coefficients under different openings.The flow rate and flow resistance experiments are carried out for the multi-stage sleeve control valve,and according to the experimental data,the flow coefficient comparison between simulation and experiment is plotted,and the error between virtual model and solid model is about 8%.Write a data acquisition module for the digital twin modeling system,which can take the measured values from the sensors,collect and save them,and make the basis for the data transmission in the UI interface.4.Based on fluid simulation software to simulate the velocity,pressure,turbulence kinetic energy clouds at different openings,and set the detection curve to analyze the flow characteristics of high parameter multi-stage sleeve control valve,with full openness control valve as an example,other openings to do a comparison to conclude that with the increase in openness,the velocity at each part of the valve will also become larger,but the velocity at the sleeve throttle hole is slightly different,showing the phenomenon of higher openness in the middle and lower openness velocity on both sides,a wide range of vortex flow mainly occurs in the valve cavity back wall surface and the bottom of the valve body in the outlet direction,for multistage sleeve control valve noise characteristics indicate the direction and give support.5.Aerodynamic noise simulation of the full-opening multi-stage sleeve control valve,to obtain the sound power level distribution cloud map of the internal flow channel and wall,the location of the sound power is mainly located in the third sleeve of the throttle hole and the seat sleeve throttle hole and the basin around the seat plug,and the multi-stage sleeve control valve noise directional distribution study,the highest amplitude of sound pressure level in the outlet direction,and according to the noise monitoring points According to the analysis of the 1/3 octave diagram of the noise monitoring points,the pneumatic noise of the multi-stage sleeve control valve exhibits a continuous broad frequency characteristic dominated by high frequency.The noise characteristics of the multi-stage sleeve control valve were improved by arranging the throttle plate at the outlet and analyzing the noise characteristics of the improved multi-stage sleeve control valve.The noise pressure level at different frequencies was reduced by about 20 d B.