Abstract The single-phase and two-phase flow models are developed and compared for the performance evaluation of a steam ejector for the multi-effect distillation with thermal vapour compression (MED-TVC) seawater desalination system. The results show that a single-phase flow model with ignoring the phase change predicts an unphysical temperature of the steam in the supersonic flow with the minimum value of approximately 122 K, which raises the query of the formation of the ice. The two-phase wet steam model corrects the distribution of the flow parameter by predicting the heat and mass transfer during the phase change. The steam achieves the first nonequilibrium condensation process inside the primary nozzle and another four alternating condensation and re-evaporation processes. The single-phase flow model under-predicts the entropy loss coefficient by approximately 15% than the two-phase wet steam model. The performance comparison is achieved against the single-phase model to present the accuracy of the two-phase model for the steam ejector simulation. This demonstrates that the nonequilibrium condensation is essential for the performance analysis of steam ejectors for MED-TVC seawater desalination system.

中文翻译：

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非平衡冷凝蒸汽喷射器用于热蒸汽压缩（MED-TVC）海水淡化系统多效蒸馏的性能

摘要 开发了单相流和两相流模型，并比较了用于热蒸汽压缩多效蒸馏 (MED-TVC) 海水淡化系统的蒸汽喷射器的性能评估。结果表明，忽略相变的单相流模型预测了超音速流中蒸汽的非物理温度，最小值约为122 K，这引发了对冰形成的质疑。两相湿蒸汽模型通过预测相变过程中的传热传质来校正流动参数的分布。蒸汽在主喷嘴内实现第一次非平衡冷凝过程，然后再进行四次交替冷凝和再蒸发过程。单相流模型比两相湿蒸汽模型低估了熵损失系数约 15%。与单相模型进行了性能比较，以展示用于蒸汽喷射器模拟的两相模型的准确性。这表明非平衡冷凝对于 MED-TVC 海水淡化系统蒸汽喷射器的性能分析是必不可少的。