Numerical Simulation And Experimental Study Of Long-Waist Cone Throttling Device

Differential pressure flowmeter is the most widely used flowmeter in industry, such as, petroleum and gas production, chemical engineering. The cone flowmeters, as a newly developed differential pressure meter, have received growing attention of engineers and academic researchers in multiphase flow measurement. It can accurately measure multiphase flow rate in a less straight pipe. However, there is still need to optimize the cone structure and improve the performance of cone meters. In this paper, a deformation of cone meter is presented, and its flow field in a horizontal pipe of 50 mm inner diameter were numerically simulated with Computational Fluid Dynamics (CFD) method, and the hydraulic characteristics of the cone of different structural parameters are analyzed to optimize the structure. The simulation shows that the optimal structure can significantly reduce the permanent pressure loss and improve the measurement repeatability and accuracy.This paper aims at long-waist cone throtting device, basing on three-dimensional CFD and multiphase flow experimental studies, researching on the modulation of the long -waist cone, and analyzing the flow characteristic of the long-waist cone throtting device. The main work includes: the mathematical models of long-waist cone throtting device; the numerical study using CFD; designe and manufacture long-waist cone flowmeter for experiment; calibration for experiment.Firstly, we annlyse the measuring principle of long-waist cone throtting device, and derivate the functions between differential pressure/permanent pressure loss and flow rate using the hydrodynamic theory and the experiential formula, and put forwad the double-differential pressure model of long-waist cone flowmeter.Secondly, the flow field of long-waist cone throtting device is studid by CFD software, Fluent 6.3. The main work includes: building the long-waist cone's geometrical model by Gambit 2.6; choosing proper turbulence model for computing; setting reasonable boundary conditions. We study long-waist cone thortting device in three steps and get the optimal structure.Then, a series of long-waist throtting devices, whose diameter is 100mm, are designed according to the results of simulations. The tube is made of transparent material, plexiglass.. Finally, we do a calibrational experiment with the diameter ratio of 0.55. Calibrating the discharge coefficient, Cd,Cp and the rato between differential pressure and permanent pressure loss, etc. Preliminary anslysing the characteristics of long-waist cone flowmeter, laying the foundation for the multisensor's optimization and building the measurmental model under the conditions of the flow field in annular channel coupling with the electric field.