Research On Measurement Characteristics Of Cementing Mud Flowmeter

Cementing mud flowmeter is a tool used to measure the flow of liquid cement and drilling fluid in cementing engineering.It is a tangential turbine flowmeter.Accurate measurement of liquid cement flow is of great significance to the successful implementation of drilling and cementing engineering and to ensure the life and quality of gasoline wells.However,the theoretical research of tangential turbine flowmeter is not perfect compared with the traditional axial flowmeter,and the measured value is deviated from the actual value in the actual complex fluid measurement operation.In order to explore the measurement characteristics of cementing mud flowmeter and improve the measurement effect,this paper starts from the traditional axial flowmeter model,conducts in-depth research on the mathematical model,internal flow field characteristics,structure optimization and other directions of tangential flowmeter,providing theoretical basis for further improving the measurement effect of oilfield cementing mud flowmeter.The force analysis of the tangential impeller of the mud flowmeter under the fluid impact state is carried out to determine the driving moment and resistance moment of the impeller in the rotation process,and establish the mathematical model of instrument coefficient K according to the balance equation of the impeller movement,the factors affecting instrument coefficient are analyzed by this model.In order to explore the metering characteristics of the flowmeter,3D model of the flow meter was built,and the passive rotation process of the impeller was simulated by the fluid simulation software,so as to calculate the simulation instrument coefficient according to the relationship between the fluid and the impeller speed,analyze the instrument coefficient characteristics.Compare the simulation data with the field measured data to verify the accuracy of the established simulation model.According to the physical parameters of the fluid in the actual project,the flow field characteristics of the flow meter and the stress characteristics of the blade are simulated and analyzed based on the established fluid simulation model,and the impeller parameters for structural optimization are determined.Due to the complexity of fluid physical parameters in cementing operations,the variation characteristics of instrument coefficients in the range of fluid viscosity from 35 to 75m Pa·s and density from 1000 to 1870 kg/m~3 were simulated and analyzed,and the variation rules were summarized to provide a basis for subsequent research.Combined with the simulation analysis results,the top radius,blade edge thickness and tilt angle of the impeller blade structure were optimized.Firstly,a three-factor and four-level simulation experiment was designed,and the data were fitted by response surface method to explore the influence of different structural parameters on the target value.A crowd search algorithm based on adaptive differential variation(DESOA)was proposed to optimize the structural parameters of blades with the objective of minimizing the linearity error of instrument coefficients.The simulation results show that the optimization effect is significant.