Pulse interfacial defrosting

Abstract

Frost formation and ice accretion are major problems for a plethora of industries. Common defrosting and deicing techniques utilize energy-intensive mechanical actuation to dislodge ice/frost or heating methods to melt ice/frost from surfaces. Here, we develop an ultraefficient method to defrost/deice surfaces by spatially and temporally localizing thermal energy at the substrate-ice/frost interface. To remove ice/frost efficiently, it is beneficial only to melt the interfacial layer adhering the ice/frost to the solid surface by using a localized “pulse” of heat, allowing gravity or gas shear in conjunction with the ultrathin lubricating melt water layer to remove the ice/frost. To probe the physics of pulse defrosting, we first developed a transient numerical heat transfer model. Experimental validation of the model was achieved via pulse (≈100 ms) joule heating of indium tin oxide on glass samples. Utilizing transient heat fluxes ranging from 10 to 100 W/cm2, spontaneous melting of the interfacial ice/frost layer was achieved, leading to rapid ice removal. We employed our validated model to outline design guidelines for pulse defrosting applications, showing <1% of the energy and <0.01% of the defrosting time needed when compared to conventional thermal-based defrosting methods.