R134a flow boiling inside a high porosity copper foam

Electronic cooling challenge is focused on the high heat flux to be dissipated by the operating fluid. More efficient heat spreaders and dissipators, and more compact heat exchangers are in great demand for various applications. In the last decade, cellular structure materials and particularly open-cell metal foams have been proposed as possible enhanced surfaces for both single phase and two phase heat transfer enhancement. It is well known that cooling with a boiling fluid can be efficient; therefore,its possible use for electronic thermal management can lead to a reliable electronic packaging. This paper presents the experimental measurements carried out during flow boiling heat transfer of R134a inside a high porosity 5 PPI (Pore Per Inch) copper foam, electrically heated from the bottom. The measurements have been carried out by varying the mass velocity and the vapor quality, at 30 \ua1C of saturation temperature by imposing a heat flux of 50 kW m-2.The sample is tested in a new experimental facility built at the Dipartimento di Ingegneria Industriale of the University of Padova