Cooling effects on the heat transfer characteristics of a rectangular thermosyphon with PCM suspension fluid

• Published in: International journal of heat and mass transfer Vol. 157; p. 119955
• Main Authors: Ho, C.J., Lin, J.F., Chen, R.H., Lai, Chi-Ming
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.2020; Elsevier BV
• Subjects: Computer simulation; Cooling; Cooling effects; Enthalpy; Freezing; Heat transfer; Latent heat; Liquid phases; Mathematical models; Phase change material; Phase change materials; Supercooling; Thermosyphon; Thermosyphons; Wall temperature; Latent heat; Phase change material; Thermosyphon; Heat transfer
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2020.119955

•Cooling effects of a thermosyphon with PCM suspension were numerically and experimentally investigated.•Cooling effects are the subcooling at the cooling section and PCM supercooling.•The cooling effects affected the overall thermal performance.•Controlling the cooling wall temperature can achieve an appropriate subcooling effect. A numerical and experimental study is presented to explore the effects of cooling (the section on subcooling and phase-change material (PCM) supercooling) on the thermal performance of a rectangular thermosyphon containing PCM suspensions. In the numerical simulation, a continuum mixture flow model is used for the buoyancy-driven circulation flow of the PCM suspensions together with an approximate enthalpy model to detail the solid-liquid phase change process of the PCM particles in the loop. Parametric simulations are conducted in the following ranges: heat input at the heating section = 12 W, average temperature of the outer wall of the cooling section = 10–25 °C, and PCM mass concentration = 0–15%. The results show that in the configuration of this study, the downward flow of the high-density fluid in the cooling section became the main driving force of the circulation loop. Therefore, the cooling effects affected the overall thermal performance. To allow the proper melting/freezing of PCM particles, it is critical to control the wall temperature at the cooling section to achieve an appropriate subcooling effect.