Study on flowrate measurement model of gas-liquid two-phase flow by using double-cone flowmeter

Gas-liquid two-phase flow is encountered in chemical,power engineering,petrole-um refining,energy conversion and other industries.The parameter measurement and behavior investigation of two component flow are problems difficult to avoid for monitoring industrial sys-tems.A new flow sensing method based on a differential pressure flowmeter of a double cone structure is proposed.The new double-cone flowmeter is developed based on the V-Cone flowme-ter,which has advantages of simple and stable structure,convenient processing,and not easy to wear,etc.Five double-cone flowmeters with different diameter ratios which are 0.5,0.6,0.7, 0.8 and 0.9 are designed and manufactured.The measurement characteristics of the flowmeters for the single flow are analyzed.The total mass flowrate of gas-liquid two-phase flow is measured using the differential pressure signals.The experimental studies are conducted on the gas-liquid two-phase flow in the horizontal pipe by using the five new double-cone flowmeters.Through a-nalysis of the relationship between Lockhart-martinelli number and prospective gas flow ratio, the total mass flowrate measurement models for the total mass flowrate of gas-liquid two-phase flow are established on the basis of separated flow theory.The experimental results show that the prospective gas flow ratio has a good linear relation with the Lockhart-martinelli number. And the coefficients of the models are obtained through linear fitting.The seperated model,the Murdock model,the Lin model and the proposed models are applied to measure the total mass flowrate,and the measurement errors are analyzed and compared.The results show that the pro-posed models are more suitable than the other three models for the new doble-cone flowmeters that the total mass flowrate measurement errors of the proposed models can be within 6%.These results show that combined with the new proposed models,the new double-cone flowmeters per-form well in the flowrate measurement of the air-water two-phase flow.