| 摘要: |
| 蒸汽喷射器是喷射式制冷系统的关键设备，具有节能环保优势。本文同时考虑三维和非平衡凝结效应，优化、验证并对比了蒸汽喷射器模型。比较了考虑凝结效应的优化模型与理想气体模型的模拟结果。基于该凝结模型，研究了湍流处理方法（雷诺平均方法和大涡模拟方法）对模拟结果的影响。对比分析了不同模型捕捉到的非平衡凝结、激波等复杂流动现象。结果表明，优化后的蒸汽喷射器模型可以以最低计算成本可靠预测喷射器性能并捕捉其内部复杂流动现象，其中大涡模拟方法得到的最大液体质量分数低于雷诺平均方法，喷射系数与实验值的最大相对误差为11%；与理想气体模型相比，凝结模型可使喷射系数和临界出口压力与实验值之间的平均相对误差分别降低72.0%和29.9%。 |
| 关键词: 喷射器 大涡模拟 非平衡凝结 激波 边界层 |
| DOI： |
| 投稿时间：2024-02-20 修订日期：2024-03-18
录用日期：2024-05-07 |
| 基金项目: |
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| Optimization and comparison of 3-D model of steam ejector with nonequilibrium condensation |
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| Abstract: |
| Steam ejector is the vital equipment of jet refrigeration system, which attracts much attention because of energy saving and environmental protection. In this paper, the steam ejector models were optimized, validated, and compared considering the three-dimensional and non-equilibrium condensation effects. The simulation results of the optimization model were compared with those of the ideal gas model. Based on the condensation model, the effects of turbulence processing methods (Reynolds-averaged Navier-stokes and large eddy simulation method) on the simulation results were studied. The complex flow phenomena such as shock waves, non-equilibrium condensation, and boundary layer separation captured by different models were compared and analyzed. Results show that the optimized steam ejector model can credibly predict the ejector performance and capture the complex flow phenomena inside the ejector with the lowest computational cost. The maximum liquid mass fraction obtained by the large eddy simulation method is lower than that obtained by the Reynolds-averaged Navier-stokes method. The maximum relative error of the entrainment ratio obtained by the large eddy simulation method and the experimental value is 11%. The condensation model can reduce the average relative error of the entrainment ratio and the critical discharge pressure by 72.0% and 29.9% respectively. |
| Key words: Ejector large eddy simulation non-equilibrium condensation shockwave boundary layer |
