The numerical value of the pressure loss in the flow passage of the turbine flow meter

Abstract: The numerical information of the pressure loss of the flow passage of the turbine flowmeter is provided by the excellent flowmeter and flowmeter manufacturers. 1 Basic structure and working principle of turbine flowmeter This paper adopts CNiM-TM series 80mm diameter gas turbine flowmeter of Cangnan Instrument Factory as the research object, and carries out numerical simulation of the pressure loss of the internal flow channel. The schematic diagram of the gas turbine flowmeter is shown in the figure. More flowmeter manufacturers choose models and price quotations. You are welcome to inquire. The following is the numerical article details of the pressure loss of the flow passage of the turbine flowmeter. 1 Basic structure and working principle of turbine flowmeter In this paper, the CNiM-TM series 80mm diameter gas turbine flowmeter of Cangnan Instrument Factory is used as the research object, and the numerical simulation of the pressure loss of the internal flow channel is carried out. The schematic diagram of the gas turbine flowmeter is shown in Figure 1. The actual gas turbine flowmeter is shown in Figure 2, of which Figure 2(a) is the actual picture of the turbine flowmeter, and Figure 2(b) is the actual picture of the impeller of the turbine flowmeter movement. Fig.1 Structural diagram of gas turbine flowmeterFig.2 Actual diagram of turbine flowmeter and impeller The relationship between , the fluid velocity is obtained by measuring the impeller speed, and then the flow value in the pipeline is obtained. The pulse frequency f output by the turbine flowmeter is proportional to the measured volume flow qv, namely (1) In formula (1): k—The meter factor of the flowmeter. According to the law of motion, the motion equation of the impeller can be written as (2) In formula (2): J—The moment of inertia of the impeller; t—time; ω—Rotational speed of the impeller; Tr—Pushing torque; Trm—Mechanical frictional resistance torque; Trf—Flow resistance torque; Tre—Electromagnetic resistance torque. 2 Calculation model 2.1 Mathematical model The working medium of the numerical simulation of the turbine flowmeter is air, and the flow is in turbulent flow. The numerical simulation turbulence model adopts the Realizable K-ε model, which is suitable for simulating and calculating the boundary of rotating flow and strong inverse pressure gradient Laminar flow, flow separation and secondary flow, etc., the model equations are expressed as:——Average flow velocity in all directions; a—speed of sound;μ—dynamic viscosity coefficient;υ—Kinematic viscosity coefficient; K—Turbulent kinetic energy; ε—Turbulent dissipation rate;βT—expansion coefficient; ωk—angular velocity;—Time-average rotation rate tensor; if the influence of buoyancy is not considered, Gb = 0, if the flow is incompressible, = 0, YM = 0. 2.2 Meshing of the fluid area Use Solidworks three-dimensional design software to build the turbine flowmeter components according to the actual size Die and assembly, simplify the parts that have less influence on the fluid area, such as the spindle, the pressure hole and the oil filling hole. First perform Boolean operation on the movement part to obtain a pure fluid area, then add an envelope to the impeller to form a rotating area, and add a straight pipe section 15 times the diameter of the movement before and after the inlet and outlet of the movement to ensure that the flow at the inlet and outlet is fully developed Turbulence. The entire fluid area includes the front and rear straight pipe sections, the impeller envelope and the fluid area of ​​the core part. Use Gambit software to mesh the 3D model, optimize and simplify the parts that are difficult to generate meshes such as small faces and sharp corners in the fluid area. Areas with more complicated flow conditions such as impellers are locally encrypted, as shown in Figure 3. Among them, Figure 3(a) is the grid diagram of the fluid area of ​​the core, and Figure 3(b) is the grid diagram of the impeller. The total number of grids is about 2.3 million. Figure 3. Turbine flowmeter fluid area grid. Figure 2.3 Numerical simulation simulation condition setting. During numerical calculation, in order to facilitate the comparison between simulation results and experimental results, the settings of ambient temperature, humidity and pressure are the same as the experimental conditions. densityρand dynamic viscosityηAccording to the calculation procedure proposed by Rasmussen, the simplified formulae (5) and (6) derived by fitting are calculated and obtained: (6) In formula (5) (6): T—temperature; P—pressure; H—humidity. The solver adopts the separation, implicit and steady-state calculation methods. The turbulence model selects the Realizablek-ε turbulence model, and the pressure interpolation adopts the Body force weighted format. The turbulent kinetic energy, turbulent dissipation term and momentum equation are all discretized by the second-order upwind style. The coupling of the velocity is solved by the SIMPLEC algorithm, and the rest of the settings are the default values ​​of Fluent.

Beijing Sincerity Automatic Equipment Co., Ltd is specialized in sourcing low flow turbine flow meter mass flow meter through its unparalleled worldwide network of supply. Go to Sincerity Flow Meter, you will surely find your ideal at the most favorable price.

For more information please see our site at Sincerity Flow Meter. Don't be hesitate to contact us!

Beijing Sincerity Automatic Equipment Co., Ltd are trained to think about problems and coming up with solutions, as well as presenting the whole idea in a logical and coherent manner.