Dynamic Modeling Method Of Coriolis Mass Flowmeter Considering Uncertainty Of Measuring Tube Shape

With the unremitting pursuit of high-precision and high-reliability mass flow measurement in the fields of energy,chemical industry and medicine,the research on Coriolis mass flowmeters that can directly measure mass flow data has received more and more attention.However,due to the sensitivity of the flowmeter measurement tube vibration and the diversity of processing conditions,how to better optimize the structure of the Coriolis mass flowmeter and clarify the impact of various processing errors on its performance under the condition of ensuring measurement accuracy,In order to effectively improve the stability of fluid quality measurement,it has become a hot and critical issue in the field of fluid measurement research in recent years.People have adopted a variety of methods including simplifying the Coriolis mass flowmeter measuring tube vibration system into various analytical and numerical forms of straight tube or curved tube beam model solution analysis and experimental exploration,but so far,it has not been well solve.Therefore,on the basis of previous work,this paper mainly studies the influence of the shape error introduced by the measuring tube of the Coriolis mass flowmeter on its dynamic characteristics,which has important theoretical significance and engineering application value.According to the actual working characteristics of Coriolis mass flowmeter,the dynamic model of Coriolis mass flowmeter is constructed.On this basis,the use of the dynamic stiffness matrix method allows more vital local design information to be integrated into the dynamic equations of the Coriolis mass flowmeter system,which can greatly improve the efficiency of calculation and analysis while ensuring the calculation accuracy,Which provides an important reference for the dynamic modeling of Coriolis mass flowmeters with different shapes.Taking the double U-shaped Coriolis mass flowmeter with vibration isolation plate as an example,the finite element software ANSYS Workbench was used to analyze the Coriolis mass flowmeter for empty tube modal analysis and fluid-structure coupling modal analysis.The influence of factors such as structural parameters and vibration isolation plate thickness on the coupling mode of the Coriolis mass flowmeter reveals the rules and characteristics of the influence of different structural parameters on the excitation frequency,and the key parameters that should be further concerned and studied in production practice are obtained.Using the dynamic model of the Coriolis mass flowmeter constructed in this paper,and introducing a sample-based random modeling method,we focused on exploring the influence of the uncertain changes of relevant structural parameters on the dynamic performance of the Coriolis mass flowmeter during the bending process.The key control parameters during the bending process of the measuring tube are clarified.Finally,the accuracy and validity of the theoretical model are verified through modal experiments and water flow calibration experiments.The relevant research results can be used as a useful reference for the structural design and optimization of Coriolis mass flowmeters.