Numerical Simulation of Ammonia Flow Boiling in a Horizontal Circular Tube

Abstract:

In order to understand the variation of ammonia as a cooling refrigerant, the ammonia coolant is being used in power plant air cooling system. The subcooled boiling phase transformation of ammonia in a horizontal pipe tube was simulated through the application of the CFD fluid computational platform, the fluid state parameters in the tube were given at the same time. The speed variation along the axis of the tube was obtained, the speed is increasing, the Reynolds number corresponding substantial increase in the convective heat transfer coefficient corresponds to raise; The vapor volume fraction and boiling heat transfer coefficient along the tube were obtained. The boiling can strengthen the heat transfer significantly. The results showed that the ammonia as a cooling refrigerant by raising the Reynolds number and the use of the latent heat absorb these dual characteristics to improve the heat transfer coefficient is worth promoting.

• Periodical: Advanced Materials Research (Volumes 718-720)
• Pages: 162-165
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.718-720.162
• Online since: July 2013
• Authors: Sheng Long Wang, Yin Hai Ge, Wen Hao Li
• Keywords: Flow Boiling, Numerical Simulation, Phase Change Heat Transfer, Working Fluid of Ammonia

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