Performance Test and Flow Pattern Simulation of Small Diameter Thermosyphons

Abstract:

Thermal transfer behavior of small diameter thermosyphons with different fill ratio, the inner and outer temperature response at start-up, and the calculated vapor-liquid two-phase vertical flow regimes were studied. The thermosyphons were fabricated by different diameter glass tubes. The present study suggests that the best thermal conductive performance is obtained with 26% fill ratio. Inner and outer thermal behaviors were experimentally studied with innovative methods of attaching thermocouples on thermosyphon walls from both inside and outside. Experimental results indicated a very good temperature uniformity of thermosyphons. Furthermore, a 2D, planar CFD modeling using explicit Multi-Fluid VOF model in the Eulerian multiphase model was carried out to model the interaction/interface between gas and liquid as well as fluid flow movement inside the tube. Real-time vapor bubble generation, combination and vapor slug maps were derived from the simulation. A good agreement was observed between CFD acquired data and experimental observations. It is evidenced that CFD is a powerful tool to model and examine the complex flow and heat transfer in a thermosyphon.

• Periodical: Advanced Materials Research (Volumes 634-638)
• Pages: 3782-3787
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.634-638.3782
• Online since: January 2013
• Authors: Shu Lei Zhao, Xiao Tian Ding, Zheng Yuan Wei, Gui Fang Liu
• Keywords: Computational Fluid Dynamics (CFD), Eulerian Multiphase, Phase Interaction, Temperature Response Behavior, Thermosyphon

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