Electrohydrodynamic Conduction Pumping-Driven Liquid Film Flow Boiling on Bare and Nanofiber-Enhanced Surfaces

摘要

Liquid film flow boiling heat transfer driven by electrohydrodynamic (EHD) conduction pumping is experimentally studied on a surface with a novel metal-plated nanofiber-mat coating. The nanotextured surface is formed on a copper substrate covered by an electro-spun polymer nanofiber mat, which is copper-plated as a postprocess. The mat has a thickness of about 30 nm and is immersed in saturated HCFC-123. The objective is to study electrowetting of the copper-plated nanofiber-enhanced surface via EHD conduction pumping mechanism for the entire liquid film flow boiling regime leading up to critical heat flux (CHF), and compare it to the bare surface without EHD-driven flow. The results show that with the combination of these two techniques, for a given superheat value, enhancement in heat flux and boiling heat transfer coefficient is as high as 555% compared to the bare surface. The results are quite promising for thermal management applications.