Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
INFLUENCE OF COPPER FOAM THICKNESS ON POOL BOILING OF HFE-7100
Submission Author:
Leonardo Manetti , MS
Co-Authors:
Leonardo Manetti, Reinaldo Rodrigues de Souza, Elaine Maria Cardoso
Presenter: Leonardo Manetti
doi://10.26678/ABCM.COBEM2019.COB2019-1971
Abstract
Pool boiling is a low-cost technique for cooling electronic devices; HFE-7100 is a dielectric fluid with advantageous properties for such application but it is a wettable fluid that causes a temperature overshoot in the system. Hence, the use of porous heating surface improves the heat transfer performance, eliminating the temperature overshoot due to their interconnected porous which increase the wetted area and active nucleation site density. In this work, we carried out pool boiling tests by using HFE-7100 and copper foams at three different thicknesses: 3 mm, 2 mm, and 1 mm in order to study the vapor bubble dynamics into the foam cell and find out an optimum thickness to enhance the boiling heat transfer. The results show that high thickness has the best performance at low heat fluxes while lower thickness has the best performance at high heat fluxes. At low heat fluxes, the higher wetted area increases the natural convection zone even though the latent heat also plays an important role. At high heat fluxes, the vapor bubbles are trapped at the foam structure leading to an unstable boiling pattern and stops the liquid from rewetting the surface.
Keywords
pool boiling, HFE-7100, porous surface, copper foam, foam thickness
