Numerical study on the two-phase flow pattern and temperature distribution in a loop thermosyphon as a defrost device at the evaporator in the refrigerator
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This paper discusses the two-phase flow pattern and temperature distribution in a loop thermosyphon as a defrost device at the surface of the evaporator in the refrigerator with different heater locations and different heating power. A computational fluid dynamics (CFD) study was carried out using ANSYS FLUENT 15.0. The volume of fluid (VOF) model was considered to simulate evaporation and condensation at the heater surface using user-defined functions (UDFs). 2D geometries were developed with a heater inserted in the loop thermosyphon. The simulation results were verified using Fadhl’s experimental and numerical temperature data . The maximum difference is 2.4 % between the calculated data and Fadhl’s data. The two-phase flow pattern and the temperature field varied with the different heater locations and heating power values. The thermal performance was evaluated based on the average temperature and temperature uniformity inside the loop thermosyphon.
KeywordsLoop thermosyphon Location of a heater Heating power Evaporation and condensation Temperature uniformity inside the loop thermosyphon Average temperature inside the loop thermosyphon
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- W. Kalata, K. J. Brown and R. J. Schick, Injector study via VOF: Emphasis on vapor condensation due to spray, 23rd Annual Conference on Liquid Atomization and Spray Systems (2011).Google Scholar
- W. Lei, L. Yanzhonga, L. Zhan and Z. Kanga, Numerical investigation of thermal distribution and pressurization behavior in helium pressurized cryogenic tank by introducing a multicomponent model, 25th International Cryogenic Conference & International Cryogenic Materials Conference (2014).Google Scholar
- Y. U. Gu, D. K. Jeong, J. H. Hwang, Y. H. Kwon and J. S. Kim, Study on defrost of evaporator using bubble jet loop heat pipe as a defrost device, 10th International Heat Pipe Symposium (2011).Google Scholar
- ANSYS FLUENT, Theory Guide (Release 15.0). Multiphase Flows, ANSYS, Inc. (2013) 465–600 (chapter 17).Google Scholar
- Thermo–physical properties of fluid system, NIST webbook, NIST database, http://webbook.nist.gov/chemistry/fluid/.Google Scholar