Visualization Experiment on the Start-up Performance of the Close Loop Pulsating Heat Pipe

Abstract:

Through the visualization experiment, the behavior evolution of the vapor and liquid slugs in the pulsating heat pipe (PHP) was investigated in the start-up process. Optical visualization results indicate that the flow pattern mainly is slug flow in the start-up process. In the early stage of the start-up process, the distribution of vapor and liquid slugs was random at the beginning, and then gradually develops to the other form which can easily pulsate in the PHP. In the later stage, pulsation stagnation in short time and reversing of the flow direction of the working fluid could be found at low heat load, when there exists the circulation flow in the PHP. Circulation was formed along a certain direction at high heat load. In addition, the PHP can be started up with less time and lower minimum start load by using working fluid which has lower latent heat.

• Periodical: Advanced Materials Research (Volumes 550-553)
• Pages: 3150-3154
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.550-553.3150
• Online since: July 2012
• Authors: Xun Wang, Cheng Si Yang, Xin Xin Mao, Tong Han
• Keywords: Pulsating Heat Pipe, Slug Flow, Start-Up Performance, Visualization Experiment

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