Structural Reliability Optimization Design Of V-Cone Flowmeter

With the development of science and technology, more and more flow measurement methods are applied in the fields of industry. The differential pressure flow meter, which is represented by orifice, nozzle and Venturi tube, has been successfully applied in flow measurement. However, due to the weakness of its own structure, the orifice plate and other differential pressure flow meter have some disadvantages, such as method of the center contraction to obtain the differential pressure. In view of the above problems, the optimization and improvement of the measurement device have been carried out. In recent years, the emergence of V cone flowmeter makes people have a deeper understanding of the differential pressure flowmeter. It will flow throttle shrink to the pipe axis center of throttle evolved into the coaxial installation in the pipeline cone fluid contraction to the pipe wall, through measuring cone before and after the pressure to measure.V cone flowmeter is a new generation of differential pressure type flowmeter which is generally popular in the world. According to some domestic and foreign document 1,2,3,4 introduced,it processes outstanding advantages comparing with the traditional differential pressure flowmeter, namely V type interal cone flowmeter has strong self-rectifying function,and it requires the flowmeter of the front straight pipe section is short,which can be achieved in a smaller space for installation;Meanwhile it has strong capability of antipollution,lasting and durable characteristic;the low pressure loss of the V type internal cone flowmeter can reduce energy consumption,and V-cone structure without movable parts makes it good repeatability; In addition,V-cone Flowmeter has a wide range namely high linearity,which means higher fineness.However, V-cone Flowmeter except the above advantages also has some drawbacks.As the cone type throttling device is placed in the center of pipeline, it will stress great load and fluid impact during operation. If V-cone bears great asymmetric load when error appears in manufacture and installation, and holding part bears huge stress and strain, it will cause errors of measure results from some small extent and reduce fineness, but from some great extent, it can drop application reliability of flow meter making V-cone falling off.In this paper,I mainly give an analysis of the structure of the V cone flowmeter and the structure optimization design,which makes the structure of the optimized design higher reliability and the overall structure more excellent.Before starting V cone flowmeter reliability optimization design,I firstly conduct the hydromechanical simulation forthrottling device of flow meter, and get a knowledge of the pressure condition of cone type structure stressed by fluid; secondly carry through the structural finite element analysis, at last start reliability analysis and optimization design. Finally I conducted the fluid calibration analysis for optimized structure and I find that it has |0.0005| flow coefficient difference between the optimized structure and the original, and it turns out that the optimized structure don’t influence the using features of flow meter. Meanwhile, by the way of simulation experiment, it proves out the effect on measuring stability when the end of throttling device is flapped up and down, which means when the fluctuation is in the small range,it has little impact on measuring stability,and with fluctuation increase, impact on the stability of the measurement becomes more and more prominent.