Coriolis Mass Flowmeter Sensor Fluid-Solid Coupling Analysis And Development

Coriolis mass flowmeter based on Coriolis effect is a high precision flowmeter.The structural parameters of the sensor part directly affect the performance parameters such as natural frequency,vibration mode and phase difference.In order to study the relationship between the two,the fluid-solid coupling analysis method is used to study the factors affecting the performance of the CMF sensor.On the basis of optimizing the structure parameters,the CMF sensor phase difference detection experimental platform is designed and built,and the preliminary experimental test is completed,which provides a basis for the optimization of the sensor structure.The main research contents are:（1）On the basis of modal analysis and fluid-solid coupling analysis,taking double U-shaped CMF as an example,the settings of modal analysis and bidirectional fluid-solid coupling analysis are introduced.After the analysis is completed,the interpolation method is used to process the two vibration signals,and the time difference is accurately calculated to reduce the error caused by data processing.The reliability of the bidirectional fluid-solid coupling analysis method for CMF numerical simulation analysis is verified by the fluid-solid coupling vibration analysis at different flow rates and the comparison of the data in the literature.（2）The fluid-solid coupling modal analysis and fluid-solid coupling vibration analysis method are used to study the dual U-shaped CMF sensor with damping plate.The influence of different structural parameters（straight pipe L₇,L₈,elbow radius R₃,R₄,wall thicknessδ）on the natural frequency,vibration mode,phase difference,time difference and amplitude is analyzed.The research results show that by optimizing the structural parameters,the natural frequency of CMF can be adjusted to avoid field interference and signal analysis.At the same time,the phase difference and amplitude of the output signal can be increased to facilitate signal detection,improve detection sensitivity and ensure measurement accuracy.（3）According to the optimization results,the CMF sensor was fabricated and the preliminary test was carried out to measure the phase difference and its repeatability under different mass flow rates.The experimental results show that the relative error between the experimental phase difference of CMF sensor and the simulation phase difference is within±10%.Repeatability is better than 0.1%;the relative error between the CMF sensor developed in this paper and the standard flow device is within±5%,which reaches the preliminary stage of the development of CMF sensor.