Two-phase flow simulation in mixing chamber of steam jet ejector

doi:10.11949/j.issn.0438-1157.20161644

Abstract

Abstract:

Fluid flow in steam jet ejector was simulated by employing wet steam model for transonic flow. The study focused on fluid flow in mixing chamber of steam jet ejector and compared difference in simulation results between ideal gas and wet steam models. Higher entrainment ratio of steam jet ejector, smaller localized high pressure produced by shock waves near nozzle outlet and ejector inlet, and less reduction in velocity and temperature of primary steam were observed in wet steam model than in ideal gas model.

Key words: steam ejector, mixing chamber, condensation, wet steam model, entrainment ratio, vapor-liquid two-phase flow, numerical simulation

摘要：

应用适用于跨声速流动的湿蒸汽两相流模型对蒸汽喷射器内流体的流动进行了数值模拟研究。重点研究了蒸汽喷射器混合室内流体的流动过程，并比较了采用湿蒸汽模型和理想气体模型计算结果差异。研究结果表明，湿蒸汽模型中，蒸汽喷射器引射系数略高于理想气体模型的，混合室内喷嘴出口和引射蒸汽入口附近激波产生的局部高压明显小于理想气体模型的，工作蒸汽速度、温度的降低也要比理想气体模型的小。

关键词: 蒸汽喷射器, 混合室, 凝结, 湿蒸汽模型, 引射系数, 气液两相流, 数值模拟

CLC Number:

TQ026.2

WU Hongqiang, LIU Zhongliang, LI Yanxia, FU Weina, TANG Yongzhi, SHI Can. Two-phase flow simulation in mixing chamber of steam jet ejector[J]. CIESC Journal, 2017, 68(7): 2696-2702.

武洪强, 刘中良, 李艳霞, 付维娜, 汤永智, 石灿. 蒸汽喷射器混合室两相流动的数值模拟[J]. 化工学报, 2017, 68(7): 2696-2702.

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