Effect of Electric Field Distribution Generated in a Microspace on Pool Boiling Heat Transfer

摘要

This study describes the effect of an electric field on nucleate boiling and critical heat flux (CHF) in pool boiling. A dielectric liquid of AE-3000 was used as the working fluid. A heating surface was polished to a surface roughness of 0.05 μm. A microsized electrode, in which slits were provided, was designed to generate a nonuniform electric field and produce electrohydrodynamic (EHD) effects with the application of high dc voltages. The obtained results confirmed CHF enhancement as the EHD effects increased CHF to 86.2 W/cm~2 with a voltage of -3000 V, which was four times greater than pool boiling in the absence of the electrode. The usual traveling wave on the bubble interface, induced by the Kelvin-Helmholtz instability, was modified by adding the EHD effects. The traveling wave model exhibits the essential features of the phenomenon and shows good agreement with the experimental data.