| 摘要: |
| 在冷凝过程中采用气液分离（分液冷凝）能同时实现强化传热和降低压降。高效的气液分离是提升分液冷凝器性能的关键。本文针对联箱-小孔型气液分离器，建立了三维数值模型，研究了其气液分离特性。基于实验结果对模型进行了验证，分析了分液孔径（0.5~2 mm）和分液孔位置（居中、不居中）对联箱内工质流动特性的影响。结果表明：在入口流量为3 g/s，入口干度为0.5时，分液效率和漏气率随着分液孔的增大而逐渐增大；在孔径为1.6 mm，分液孔居中时有最优的气液分离性能，此时分液效率为70.23%，漏气率为0.14%。分液孔位置主要影响分液孔处速度分布和压力分布，当孔径为2 mm且分液孔不居中时，其气液惯性力比值可达1.51×10-2，因此，不合理的分液孔大小和位置导致分液孔处存在“冲击现象”。 |
| 关键词: 气液分离 冷凝器 分液孔 分液效率 |
| DOI： |
| 投稿时间：2021-06-23 修订日期：2021-09-23
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| 基金项目:国家自然科学基金（No.51736005）资助项目。 |
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| Simulation of Vapor-liquid Separation in Header-baffle with Hole using Computational Fluid Dynamics |
| Huang Kunteng,Chen Jianyong,Chen Ying,Luo Xianglong,Yang Zhi,Liang Yingzong |
| (School of Material and Energy, Guangdong University of Technology) |
| Abstract: |
| The implementation of vapor-liquid separation during condensation enhances heat transfer and reduces the pressure drop simultaneously. The vapor-liquid separator is vital for the performance improvement of such liquid-separation condensers. This study focuses on a header baffle with a small hole as the vapor-liquid separator. A 3D numerical model for the separator was established to investigate the vapor-liquid separation characteristics. The model was validated by experimental data first, and then it was used to analyze the effects of hole diameter (0.5–2 mm) and hole position (centered or not) on the flow features of the working fluid in the header. The results showed that when the inlet mass flow rate was 3 g/s and the inlet vapor quality was 0.5, the liquid-separation efficiency and vapor drainage ratio increased with increasing hole diameter. The best performance is achieved when the hole diameter is 1.6 mm and centered. In this case, the liquid-separation efficiency was up to 70.23%, and the vapor drainage ratio was 0.14%. The hole position mainly affects the velocity and pressure distributions. It was found that the vapor-liquid inertial force ratio can reach up to 1.51×10-2 as the hole diameter is 2 mm and its position is not centered. Hence, the unreasonable arrangement of hole diameter and position could lead to “fluid impact” at the liquid-separation hole. |
| Key words: liquid-vapor separation condenser liquid-separation hole liquid-separation efficiency |
