Latest news

Alexandre Marie has defended his thesis on control and intensification of heat transfers

On 25th january 2019, Alexandre Marie has defended his thesis. Awarded by the University of Toulouse, his work was supervised by Laplace/PPRIME, the MEGEP doctoral school, and IRT Saint Exupéry. Alexandre published his thesis, in the framework of the SOCOOL project (SOlutions for COOLing).

Thesis Subject

“Heat and mass transfer control and intensification by means of capillary forces : conception and analysis of an evaporator with decoupled thermal and hydraulic performance”

About this thesis

Given the “more electrical aircraft” industrial problematic, the thermal management of multiple and scattered dissipative components appears to be a crucial technological issue. In particular, the use of multiple evaporators, integrated into a unique cooling system, is frequently considered. However, actual control of the vaporization phenomenon occuring in an evaporator which is supplied in liquid by an external source (imposed by the complete cooling system) is still problematic.

Considering that it is necessary to overcome this limit to optimize the associated thermal and hydraulic performances, a particular evaporator architecture has been considered. This architecture, based on the utilization of local capillary pumping, may indeed allow the expansion and evaporation of liquid films on a heated surface independantly from the liquid flow rate supplied to the device. To this end, a dedicated experimental system has been set up. It consists of an evaporator designed according to such an architecture and an associated test bench allowing the characterization of both the thermal and hydraulic behavior of the prototype. The experimental results allowed to describe the general operation of the device in terms of liquid and vapor phase repartition, whereas temperature and pressure measurements allowed to quantify the hydraulic equilibriums and heat transfer coefficients associated to this configuration. Simultaneously with this experimental approach, several modelling efforts have been conducted.
First, an analytical model of the hydraulic equilibrium associated to the evaporator assembly permitted to quantify the mechanisms that cause the distinct operating modes observed as well as predicting their limits. Then, a numerical resolution of the liquid flow and heat transfer occuring on the heated surface has been developed to assess the influence of different physical parameters on the measured heat transfer coefficients. Finally, a first procedure allowing a geometric optimization of capillary structures adapted to this experimental configuration has been established in the objective of enhancing the evaporative heat transfer and/or extending the operating range of the device.  


Socool: Looking at cooling solutions for any environment


Related Publications

Evaporateur à alimentation hybride pour boucle de refroidissement fluide” -A. MARIE, P. LAVIEILLE, M. MISCEVIC, L. LACHASSAGNE, V. DUPONT- 2018
“Etude expérimentale d’un évaporateur constitué de micro-canaux à deux dimensions caractéristiques-A. MARIE, P. LAVIEILLE, M. MISCEVIC, L. LACHASSAGNE, V. DUPONT- 2018
“Experimental investigation of a capillary-assisted high performance evaporator” -A. MARIE, P. LAVIEILLE, M. MISCEVIC, L. LACHASSAGNE, V. DUPONT- 2018