Flow boiling heat transfer performance of copper-alumina micro-nanostructured surfaces developed by forced convection electrodeposition technique

The stability and adhesion of developed surfaces to the substrate is directly influenced the boiling performance with respect to the recurring trial runs. For the commercial application point of view, the stability of developed surfaces is an important concern. Therefore, a new multi-step forced convective electrocodeposition technique is proposed for further improvement in adhesion, nucleation sites, wettability, and flow boiling heat transfer. The uniform particles deposition on the surface is achieved by forced convection electrodeposition technique. The SEM images, porosity, wettability, coating thickness, EDS spectrum, and surface roughness are carried out in order to analyze the surface behaviors of the surfaces. The flow boiling tests are conducted on considered surfaces at different mass flow rates with DI water. The maximum variations of 5.3% in critical heat flux (CHF) and 1.3C in surface temperature are monitored for micro-nanostructured (MS#2) surface between the first and fifth test run. The incipience of boiling (ONB) for MS#2 surface is occurred at surface temperatures of 100.3, 102.1, 103.4, and 106.5C for the mass fluxes of 53, 113, 268, and 361 kg/m2s, respectively. The maximum augmentation in CHF (-176%) and heat transfer coefficient (-200%) are achieved on MS#2 surface at lower mass flux. Statement of novelty and Significance: The boiling heat transfer mechanism is an efficient heat transfer mode and able to achieve large amount of heat extraction with very small wall superheat temperature from the critical equipments though sensible heat and latent heat of vaporization. In boiling heat transfer process, being a vigorous process, the stability and adhesion of developed surfaces to the substrate is directly influenced the boiling performance with respect to the repetitive test runs. For the commercial application point of view, the stability of developed surfaces is an important concern. Therefore, In the present study, a new four-step (deposition-sintering-deposition sintering) forced convection electrodeposition technique is conceptualized and used in the present work for further improvement in adhesion, nucleation sites, wettability, and boiling heat transfer. The flow boiling tests are conducted on micro/nanostructured surfaces at different mass flow rates with DI water (working fluid). More improvements in CHF and HTC have been monitored with the developed micronanostructured Cu-Al2O3 (MS#2) surface.