Skip to main content
Article thumbnail
Location of Repository

Bubble spreading during the boiling crisis: modelling and experimenting in microgravity

By Vadim Nikolayev, D Beysens, Yves Garrabos, Carole Lecoutre and D Chatain

Abstract

International audienceBoiling is a very efficient way to transfer heat from a heater to the liquid carrier. We discuss the boiling crisis, a transition between two regimes of boiling: nucleate and film boiling. The boiling crisis results in a sharp decrease in the heat transfer rate, which can cause a major accident in industrial heat exchangers. In this communication, we present a physical model of the boiling crisis based on the vapor recoil effect. Under the action of the vapor recoil the gas bubbles begin to spread over the heater thus forming a germ for the vapor film. The vapor recoil force not only causes its spreading, it also creates a strong adhesion to the heater that prevents the bubble departure, thus favoring the further spreading. Near the liquid-gas critical point, the bubble growth is very slow and allows the kinetics of the bubble spreading to be observed. Since the surface tension is very small in this regime, only microgravity conditions can preserve a convex bubble shape. In the experiments both in the Mir space station and in the magnetic levitation facility, we directly observed an increase of the apparent contact angle and spreading of the dry spot under the bubble. Numerical simulations of the thermally controlled bubble growth show this vapor recoil effect too thus confirming our model of the boiling crisis

Topics: [ PHYS.PHYS.PHYS-FLU-DYN ] Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], [ PHYS.MECA.MEFL ] Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], [ PHYS.MECA.THER ] Physics [physics]/Mechanics [physics]/Thermics [physics.class-ph]
Publisher: Springer
Year: 2006
DOI identifier: 10.1007/BF02870375
OAI identifier: oai:HAL:hal-01262855v1
Provided by: Hal-Diderot

Suggested articles


To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.