CFD simulation of degas process in medium consistency pump and experiment

Asian Working Group- IAHR's Symposium on Hydraulic Machinery and Systems

Ye, D.X.^1 ; Li, H.^3 ; Lai, X.D.^2

Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu, China^1

School of Energy and Power Engineering, Xihua University, Chengdu, China^2

National Research Center of Pumps, Jiangsu University, Zhenjiang, China^3

关键词: Exhausting process;    Experimental set up;    Gas;    liquid two-phase flows;    Gas-liquid distribution;    Gas-liquid separation;    Monitoring system;    Performance characteristics;    Turbulence generators;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/163/1/012007/pdf
DOI  :  10.1088/1755-1315/163/1/012007

来源: IOP

【 摘 要 】

The principal of this work is to simulate the degas process and study experimental performance of medium consistency pump. Based on the actual running performance of the MC pulp pumps, the gas-liquid two-phase flow in the pulp pump was numerically simulated, adopting the Eeulerian gas-liquid two-phase flow model and the RNG k- turbulence model. The gas-liquid separation and the gas exhausting process were verified based on the gas-liquid distribution inside the turbulence generator and the pump impeller. The impacts of the standpipe liquid level and the vacuum degree of the vacuum pump to the gas discharging effects were studied. The optimal standpipe liquid level, 5.5m, the critical standpipe liquid level, 3.8m, and the critical degree of the vacuum pump, 0.2atm, were defined and obtained from the simulation. Two methods were presented both enhance the gas discharging effect and decrease the flow loss from the suction hole of the MC pulp pump. A sonar flowmeter and monitoring system is used to experimental set up, and the performance characteristics of MC pump in different conditions were studied. The demensionless analysis is applied to pulp pumping. The experimental results show that with vacuum degree increasing pump head increased and gas fraction decreased at pump outlet, and the maximum flow rate increases.