Skip to Main content Skip to Navigation
Theses

ÉBULLITION SUR SITE ISOLÉ : ÉTUDE EXPÉRIMENTALE DE LA DYNAMIQUE DE CROISSANCE D'UNE BULLE ET DES TRANSFERTS ASSOCIÉS.

Abstract : Boiling phenomenon, from an energetic point of view, presents a real stake in many fields. This thesis presents an experimental study of a single vapour bubble created under a downward facing heating element which allows us to control its growth up to significant sizes. Two techniques, an optical (image processing) and a thermal (heat fluxmeter, thermocouples), are used simultaneously. The first part of this thesis deals with heat and mass transfers in a degassed liquid (FC-72). The influence of several significant parameters (heating power, liquid subcooling and inclination) on the boiling phenomenon is studied by systematic experimentation. The bubble growth in our experimental configuration is analyzed and leads to a growth law in tn, where the exponent “n” is only function of the thermal parameters. The evaporative heat flux is quantized and contributes only slightly to the improvement of the heat transfers in ebullition. There is an obvious correlation between the heat transfers and the frequency of emission of the vapour bubbles. The increase in the latter improves the transfers. The second part of the thesis deals with liquid flows around the vapour bubble which are due to thermocapillary convection (Marangoni). They only occurred with a non degassed liquid, and are a result of the presence of incondensable gas dissolved in the FC-72. The various flow rates (stationary and oscillatory) are emphasized and the limiting curve of transition between these two rates is defined. These different results have enabled us to validate the use of the heat fluxmeter, which is an original measuring device.
Complete list of metadatas

Cited literature [139 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00067749
Contributor : Magali Barthes <>
Submitted on : Sunday, May 7, 2006 - 8:19:34 PM
Last modification on : Thursday, January 18, 2018 - 1:27:01 AM
Long-term archiving on: : Saturday, April 3, 2010 - 11:19:34 PM

Identifiers

  • HAL Id : tel-00067749, version 1

Collections

Citation

Magali Barthes. ÉBULLITION SUR SITE ISOLÉ : ÉTUDE EXPÉRIMENTALE DE LA DYNAMIQUE DE CROISSANCE D'UNE BULLE ET DES TRANSFERTS ASSOCIÉS.. Physique [physics]. Université de Provence - Aix-Marseille I, 2005. Français. ⟨tel-00067749⟩

Share

Metrics

Record views

344

Files downloads

1122