Abstract The spontaneous condensation process takes place in many power engineering machines and devices, such as steam turbines, supersonic separators, ejectors etc. In the paper, the effect of the inlet steam superheat degree in steam condensing flow through the IWSEP (International Wet Steam Experimental Project) nozzle was investigated experimentally and numerically. The experiment was conducted for the low inlet pressure values under different inlet superheat conditions. The static pressure on the nozzle walls as well as the liquid phase properties in the three positions along the nozzle centreline were measured. The paper delivers new experimental data desirable for validation of the numerical models. For the numerical simulations, a condensation model using the Benson surface tension model was employed, and its accuracy was checked by comparing with the experimental data of SUT. The results state clearly that the condensation model using the Benson surface tension model can predict the spontaneous condensation process accurately, and the error is less than 5%. With the inlet steam superheat degree increasing, the condensation process moves downstream and the condensation strength weakens, and the nucleation zone range increases about 36mm. The presented results provide a good reference for further research in the field of condensing steam flows and for the improvement of both experimental and numerical methods and models.

中文翻译：

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入口蒸汽过热度对IWSEP喷嘴自凝冷凝影响的实验与数值研究

摘要 汽轮机、超音速分离器、喷射器等动力工程机械设备中都会发生自发冷凝过程。项目）喷嘴进行了实验和数值研究。实验是针对不同入口过热度条件下的低入口压力值进行的。测量了喷嘴壁上的静压以及沿喷嘴中心线的三个位置的液相特性。该论文提供了验证数值模型所需的新实验数据。对于数值模拟，采用了使用 Benson 表面张力模型的冷凝模型，并通过与SUT的实验数据对比来检验其准确性。结果表明，采用 Benson 表面张力模型的凝结模型可以准确预测自发凝结过程，误差小于 5%。随着入口蒸汽过热度的增加，冷凝过程向下游移动，冷凝强度减弱，形核范围增加约36mm。研究结果为凝汽流领域的进一步研究以及实验和数值方法和模型的改进提供了很好的参考。随着入口蒸汽过热度的增加，冷凝过程向下游移动，冷凝强度减弱，形核范围增加约36mm。研究结果为凝汽流领域的进一步研究以及实验和数值方法和模型的改进提供了很好的参考。随着入口蒸汽过热度的增加，冷凝过程向下游移动，冷凝强度减弱，形核范围增加约36mm。研究结果为凝汽流领域的进一步研究以及实验和数值方法和模型的改进提供了很好的参考。