Computational Simulation And Experimental Research On The Double-cone Flow Meter

Differential pressure flowmeter was one of the most widely usedflowmeter. But the traditional differential pressure flowmeter had many drawbacks inapplication, such as unstable efflux coefficient, higher permanent pressure loss,narrower measurement range, higher installation conditions. The development ofV-cone flowmeter had improved the optimization work of the traditional differencepressure flowmeter. However, there was still need to optimize the cone structure.This paper proposed a new kind of differential pressure flowmeter——thedouble-cone flowmeter on the basis of the V-cone structure.This paper comprehensively study the performance of the double-cone meter ina horizontal pipe of50mm inner diameter with Computational Fluid Dynamics (CFD)software Fluent and a certain amount of experiments. The main work was as follows:1) Paper study the rules of efflux coefficient of double-cone meter. We foundthat the efflux coefficient was not only related with the Reynolds number, but alsothe diameter ratio. As the Reynolds number increasing the efflux coefficientincreased and it was going to a constant. The diameter ratios had little influence onthe discharge coefficient. All the simulation results are validated by experiments andthe error of simulation is less than3%.2) A fitting scheme of expansibility factor of the double-cone flowmeter wasdeduced from the theoretical analysis method. According to this fitting scheme, twohigher precision formulas of expansibility factor were obtained by Fluent. Thecomputational predictions were compared with the results of physical experimentsand shown that the formulas of expansibility factor of the double-cone meter bynumerical simulations had higher forecasting precision. The error is less than0.5%.3) The flow filed of the double-cone flowmeter at upstream half-moon orifice、single elbow、double elbow in same plane and double elbow out of plane installationrequirement was simulated. The shortest straight pipe length of the double-conemeter under the burbling piece installation was obtained. The shortest straight pipe length for the upstream half-moon orifice was11D and the upstream elbows had noeffect on the double-cone meter when the straight pipe length was5D or above.