Thermally induced two-phase oscillating flow inside a capillary tube

✍ Scribed by S.P. Das; V.S. Nikolayev; F. Lefevre; B. Pottier; S. Khandekar; J. Bonjour

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 707 KB
• Volume: 53
• Category: Article
• ISSN: 0017-9310
• DOI: 10.1016/j.ijheatmasstransfer.2010.05.009

✦ Synopsis

This paper deals with thermally induced meniscus oscillations in a two-phase system consisting of a liquid plug and a vapor bubble in a capillary tube of circular cross-section. This system represents the simplest version of a heat transfer device called ''pulsating heat pipe" (PHP). Our purpose is to gain fundamental understanding of the physical processes that cause self-sustained thermally driven oscillations. A visualization experiment is performed and the oscillations of the liquid-vapor meniscus and the vapor pressure are observed. We propose next a theoretical model. It differs from existing models by the account of the two-phase equilibrium that occurs locally at the vapor-liquid interface and by introduction of the time varying wetting films through which the major part of the heat and mass transfer occurs. Results from the proposed model show a good agreement with the experiment.