关键词: 喷射器, 气液两相流, 相变, 引射比, CFD建模, 数值模拟

Abstract: .According to the shortage of both traditional two-dimensional design and no considering of gas-liquid phase change in numerical simulation, the ejection performance of gas-liquid ejector was simulated by CFD software. Three-dimension model was established and phase change UDF procedure influenced by time and temperature was used. The simulation results are in good agreement with experiments when phase change caused by temperature is taken into account after 40000 s. The axis velocity, pressure, temperature, entrainment ratio, volume fraction of gas and liquid were obtained by changing the inlet and outlet conditions of gas-liquid ejector. The results showed that entrainment ratio increases with inlet liquid velocity, and reasonable inlet velocity can stabilize volume fraction of gas and liquid and entrainment ratio and benefit to ejection. As outlet pressure increases, entrainment ratio decreases, while volume fraction of LNG increases. Higher outlet pressure can result in inclined flow and BOG liquefaction at the outlet of diffuser which are harmful to ejection. For the specific ejector described in this paper, it is the best ejection performance that liquid inlet velocity is from 11 to 12 m/s and mixture outlet pressue is from 0.101 to 0.304 MPa. of gas-liquid ejector was simulated by CFD software. Three-dimension model was established and phase change UDF procedure influenced by time and temperature was used. The simulation results are in good agreement with experiments whenstabilize

Key words: ejector, gas-liquid flow, phase change, entrainment ratio, CFD modeling, Numerical simulation