Development Of A Semi-physical Testbed For Coriolis Mass Flowmeters

Coriolis Mass Flowmeters(CMFs)have been widely used in the field of petroleum,chemical industry,pharmacy,food processing due to the direct measurement of liquid density and mass flow.In recent years,researchers have developed a variety of CMF digital signal processing and digital drive methods to promote the precision of phase difference detection and the stability of CMF drivers.In order to verify the effectiveness of the proposed methods,it is necessary to develop applicable experimental techniques to implement CMF verification experiments.Verification experiments based on physical CMF primary instruments have the disadvantages of high cost,space restriction and operation complexity,etc.Therefore,aiming to reduce the complexity of CMF verification experiments,the CMF semi-physical testbed based on computer simulation is proposed,which has profound prospects.The works presented in this thesis includes:(1)A semi-physical testbed for Coriolis Mass Flowmeters is developed,which is constituted of host computer,target computer and semi-physical CMF primary instrument.The semi-physical CMF primary instrument is realized as dynamic computational model,while target computer is developed based on the dual-core DSP.In addition,the development and the implantation of signal processing and digital drive software are realized through host computer.(2)CMF signal processing and CMF digital drive system are realized on the dual-core DSP.Moreover,the parallel feature of the proposed parallel CMF signal processing scheme guarantees the real-time performance of phase difference detection task.(3)The dynamic simulation of semi-physical CMF primary instrument is developed based on Timoshenko beam theory.MATLAB(Simulink)programs are employed to realize the virtualization of the semi-physical CMF primary instrument.(4)Preliminary tests of the CMF semi-physical testbed were conducted.The innovations among the above-mentioned work consist of:(1)The virtualization of the CMF primary instrument which has the advantages of better real-time performance and higher precision is realized by a new software methodology based on Timoshenko beam theory and MATLAB/Simulink software.(2)The parallel design of the CMF digital signal processing and digital drive system which proves better real-time performance is developed with a dual-core DSP.