The Numerical Simulation Of Vortex Shedding Frequency On Vortex Flowmeter

Flow is an important parameter in both chemical production process and scientific, The flow of the material flow medium, and transmission ratio, cannot leave the flow measurement and control. At present, the oil industry is very dependent on flowmeter. From the each link of the mining, storage, sales and transportation of oil all need a lot of flowmeter, so for the research and development of flowmeter has the new requirement. Vortex flowmeter is a new type of flowmeter, its fluid vibration frequency and velocity has a corresponding relation.Compared to other flowmeters, it has a higher measuring precision and range. It is also lots of advantages, like simple structure, installation is very convenient and parameter accuracy is not affected by measurement of composition, tempsure, density, the influence of pressure characteristics. But the project is relatively complicated, it is also unknown that the characteristics of vortex flowmeter like the same.Using Gambit modeling, this paper established with trapezoidal, T-shaped and circular cylinder with a slut in three different shape of vortex shedders by Grid. Numerical simulation in Newton fluid and non-Newtonian fluid carried on Fluent. Detail analysis of the monitoring location, the result showed that the location of the monitoring is not fixed. The location of monitoring which set in full development and vortex stability is better. In Newton fluid, three kinds of vortex shedders can form stable vortex and their flow field is also stable, the result found that circular cylinder with a slut vortex shedder has the most accurate measurement results. In the power law fluid, T shaped vortex shedder cannot form stable vortex, the others are better, trapezoidal vortex shedder has more accurate measurement results. Comparison of two different fluid under the various parameters of the vortex shedders, shows that trapezoidal has the best performance of three and it is the ideal vortex shedder in my paper. It’s confirmed that the parameters of the fluid has a certain impact on vortex flowmeter.Finally this paper optimize the structure of trapezoidal vortex shedder under the power law fluid. Different angle of trapezoidal vortex shedder carried on numerical simulated.Found that trapezoidal vortex shedder performed the best when the angle is 47.2°. At the time,chaged the ratio of parallel and the length of rapezoidal vortex shedder. According to the data of numerical simulation show that different ratio has a various effect to the result of measurement in the same angle. Then, numerical simulated carried on Fluent make the ratio changed in the same angle. As a result, when the angle is 45°, if want to the best measure make the ratio 0.15. when the angle is 47.2°, make the ratio 0.10.when the angle is 49°, make the ratio 0.25.Simulation results are basically identical with the experimental results, the simulation at the same time guarantee the oneness variables, design of vortex occurred body provides some reference value.