The Simulation Analysis Of Velocity Measurement Based On Electrostatic Method And Optimum Design Of Sensor

Gas-solid two-phase flow was common in the chemical industry,agriculture,metallurgy,food manufacturing,medicine,energy development,environmental protection,and other areas.Therefore,it was of great significance in industrial production to measuring the gas-solid two-phase flow accurately.Electrostatic had developed in recent years as a new sensor method.The theory of electrostatic sensor measurement was the electrostatic induction between the charges in solid particles and the sensor plates.The flow information of gas-solid two-phase flow could be detected by measuring the induction charges on sensor plates.Because of the lack of two-phase flow research,it was hard to measure the low information accurate by the electrostatic method.Therefore,this thesis was set in the velocity measurement of gas-liquid two phase flow,the analysis software ANSYS and FLUENT were the research platform,the electrostatic sensor was the research object.A series of simulations were preceded to analysis the gas-solid two-phase flow parameter.The main work of this thesis was showed as follows:(1)Different structures of electrostatic sensor and different shapes of the sensor plates had been researched and evaluted to choose out most suitable kind of sensor plates The simulation of the structural parameters of sensor had been processed.Designing the experiment,the influence of structural parameters on electrostatic sensors static sensitivity distribution was obtained.(2)Based on the analysis of the static sensitivity,the dynamic sensitivity of the sensor was analyzed and the response curve of the electrostatic sensor was obtained according to the above conditions.In addition,combining the static sensitivity and dynamic sensitivity of the sensor,the sensor which applicate the cross-correlation velocimetry was optimized based on the relevant parameters and the actual measurement conditions.(3)The simulation analysis platform for the flow simulation of charged solid-liquid two-phase flow was established with FLUENT.The corresponding UDF program was programmed to simulate the charged particles and the flowing factors of the charged fluid were analyzed.The influence of various physical parameters on the velocity distribution in the pipeline had been researched.The related research laid the foundation for the follow-up improvement of the research methods of the flow mechanism of the electrostatic two-phase flow.(4)The research platform based on ANSYS and MATLAB was established to simulate the dynamic particle motion at different positions in the sensor sensitivity space and the signal values of the upper and lower plates had been obtained to calculate the cross-correlation speed.According to the calculation results,comparing the cross-correlation speed with the actual velocity of the solid particles in the pipeline and analyzing the relationship between the two parameters,the calculated cross-correlation values are more affected by the actual solid-phase particle velocity value in a certain area in the pipeline area.Then the relationship between velocity distribution in space and measurement speed was obtained.(5)The experimental platform was set up under laboratory conditions.The charged particles were used to simulate the flow of the solid particles in the actual situation.The optimized structure of the sensor was verified.The velocity distribution was also tested,which proves the effect of velocity distribution in the sensitive space on the measurement speed.