Visualization experiment and numerical simulation of nitrogen-neon mixture condensation. (5th January 2020)

• Record Type: Journal Article
• Authors: Zhu, Shaolong; Tang, Yuan; Gu, Chenjie; Li, Yan; Zhi, Xiaoqin; Qiu, Li-Min
• Is Part Of: Applied thermal engineering. Volume 164(2019)
• Publication Date: 2020-01-05
• Subjects: Mixture condensation -- Flow pattern -- Cryogenic visualization -- CFD simulation; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2019.114492
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: Flow pattern evolution of nitrogen-neon mixture condensation is visualized. The heat transfer performance of nitrogen-neon mixture condensation is studied. An improved mass transfer model for mixture condensation is proposed. The mechanism of neon affecting mixture condensation process is revealed. Abstract: The condensation at cryogenic temperatures is rich in physics and challenging to explore, in particular for mixtures. The flow pattern evolution of liquid film for both pure nitrogen and nitrogen-neon mixture condensation is visualized. An improved mass transfer model is proposed to simulate the mixture condensation process, and the diffusion coefficient of nitrogen-neon mixed vapor and saturation temperature of nitrogen are modified. The new model agrees well with the experimental data. The complete transition process of three typical flow patterns, namely, laminar flow, two-dimensional wave flow and three-dimensional wave flow, is observed for the pure nitrogen condensation, while the Reynold number of liquid film decreases greatly during the condensation of nitrogen-neon mixture at the same condensation heat, and the fluctuation effect of interfacial waves shows attenuation. The simulation illustrates that the neon has an accumulation effect near the wall and greatly reduces the mass transfer rate of nitrogen vapor. Besides, it indicates that liquid film is the main thermal resistance for pure condensation, while the non-condensable gas layer at gas-liquid interface becomes a crucial factor affecting the mass transfer performance for mixture condensation. The mechanism of mixture condensation process is revealed through liquid film flow pattern analysis and CFD simulation results.