Research On Magnetic Fluid Flow Monitoring Of Electromagnetic Flowmeter

One of the factors to ensure the accurate measurement of electromagnetic flowmeter is the magnetic field in the sensor pipeline must be highly stable. H owever, in the measurement of magnetic fluid (such as iron ore slurry), the m agnetic material in the fluid will cause the sensor pipe magnetic instability, wh ich will directly lead to the low accurcy of flow measurement. How to get a high-presicion of flow measure of magnetic fluid with EMF is still a problem. Thus, the solution of electromagnetic flowmeter magnetic fluid detection, will greatly expand the application fields of the electromagnetic flowmeter, along wi th high theoretical significance and practical value.This paper tries to explore a method of real-time monitoring of a sensor pipeline, which could revise the magnetic field intensity timely and improve th e accuracy of the flow monitoring. The paper presented a new approach of ma gnetic field detection which is suitable for the EMF sensor pipeline. It is the s imultaneous differential-integral magnetic field strength detection method. The induced voltage obtained by the induction coil can be used as the magnetic fi eld intensity signal, and get a correction factor based on the original magnetic field, which could eliminate the influence of the magnetic field substance in th e fluid.In this paper. firstly, set up an experimental platform to confirm the feasib ility of this method mentioned before; and then create a mathematical model o f the flow meter pipe magnetic field to seek an optimal measuring position, an d the relationship between the corresponding pipeline magnetic fields and magn etic fluid containing magnetic density. Studies have shown that the best measur ement position is in the middle of the yoke, the magnetic field intensity is lin early related to the magnetic density of the fluid. After that, put analog magn etic fluid of different concentrations into the pipeline to get the data of megnet ic field strength, with these data could calculate the coefficient of the linear re lationl. With the relationship can forecast the magnetic fluid containing magneti c density for real-time. Experimental results show that, when the density of me gnetic material is between20%and30%, the accuracy of measurement is bet ween5%and8%.The magnetic field strength signal acquisition hardware part includes the el ectromagnetic flowmeter excitation circuit, constant current source circuit, signal amplifier, signal elevation circuit, AD double integral converter circuit design.The main section of the page is editted by Visual Basic6.0, Its functions include main signal acquisition, signal processing, linear regression, regression t est and the concentration prediction.