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In the present work, the effects of surface chemistry and micro/nanostructuring on the Leidenfrost temperature are experimentally investigated. The functional surfaces were fabricated on a 304 stainless steel surface via femtosecond laser surface processing (FLSP). The droplet lifetime experimental method was employed to determine the Leidenfrost(More)
The authors present highly selective emitters based on two-dimensional tantalum (Ta) photonic crystals, fabricated on 2 in. polycrystalline Ta substrates, for high-temperature applications, e.g., thermophotovoltaic energy conversion. In this study, a fabrication route facilitating large-area photonic crystal fabrication with high fabrication uniformity and(More)
After decades of intense studies focused on cryogenic and room temperature nanophotonics, scientific interest is also growing in high-temperature nanophotonics aimed at solid-state energy conversion. These latest extensive research efforts are spurred by a renewed interest in high temperature thermal-to-electrical energy conversion schemes including(More)
Keywords: Pool boiling Critical heat flux Femtosecond laser surface processing Heat transfer coefficients Metallic enhanced heat transfer surfaces a b s t r a c t In this paper, we present an experimental investigation of pool boiling heat transfer on multiscale (micro/ nano) functionalized metallic surfaces. Heat transfer enhancement in metallic surfaces(More)
In this paper, an experimental investigation of the effects of droplet diameters on the Leidenfrost temperature and its shifts has been carried out. Tests were conducted on a 304 stainless steel polished surface and a stainless steel surface which was processed by a femtosecond laser to form Above Surface Growth (ASG) nano/microstructures. To determine the(More)
Femtosecond Laser Surface Processing (FLSP) is a powerful technique for the fabrication of self-organized multiscale surface structures on metals that are critical for advanced control over energy transfer at a liquid/solid interface in applications such as electrolysis. The efficiency of the hydrogen evolution reaction on stainless steel 316 electrodes in(More)
Limited performance and reliability of electronic devices at extreme temperatures, intensive electromagnetic fields, and radiation found in space exploration missions (i.e., Venus &Jupiter planetary exploration, and heliophysics missions) and earth-based applications requires the development of alternative computing technologies. In the pursuit of(More)
In the present work, functionalized 304 stainless steel metallic surfaces were created with the use of a Femtosecond Laser Surface Processing (FLSP) technique. The laser processing technique produces self-organized micro/nanostructures on the surface. The heat transfer performance of various FLSP functionalized surfaces were characterized through pool(More)
In this paper, we present the experimental investigation of pool boiling heat transfer on multiscale (micro/nano) functionalized metallic surfaces. The multiscale structures were fabricated via a femtosecond laser surface process (FLSP) technique which forms mound-like microstructures covered by layers of nanoparticles. Using a pool boiling experimental(More)
In the present work, transition from hydrophilic to hydrophobic wetting states for an intrinsically hydrophilic surface (contact angle less than 45 degrees) using only surface microstructuring is presented. The surface microstructures are re-entrant microcavities (inverted trapezoidal microstructures) which promote air entrapment below the water droplet(More)