Abstract: Systems and methods for improved heating, ventilation, and air conditioning (HVAC) systems are provided with heat exchanger coils with improved boiling heat transfer. An etching solution may be applied to an inner surface of a heat exchanger coil to etch the heat exchanger coil to increase the surface area and the number of nucleate sites. The heat exchanger coil may be connected to a pump and the etching solution may be introduced and pumped through the heat exchanger coil for a set duration and at a set flow rate. A mass flow meter may be connected between the pump and one end of the heat exchanger coil to measure the flow rate of the etching solution. By adjusting the concentration of acid in the etching solution, the flow rate, and the exposure time, the degree to which the inner surface of the heat exchanger coil is eroded may be adjusted.

Abstract: Condensation can be an important process in both emerging and traditional power generation and water desalination technologies. Superhydrophobic nanostructures can promise enhanced condensation heat transfer by reducing the characteristic size of departing droplets via a surface-tension-driven mechanism. A superhydrophobic surface can include nanostructures of a metal oxide having further surface modification.

Abstract: A system configured for electro-thermal defrosting, desnowing and/or deicing includes (a) a component susceptible to accumulation of ice, frost, and/or snow, and (b) an electro-thermal multilayer on the component. The electro-thermal multilayer comprises a heating layer on an insulating layer, where the heating layer is configured for electrical connection to a source of pulsed power. The electro-thermal multilayer optionally includes a superhydrophobic layer. The component may be a photovoltaic panel, a wind turbine blade, a heat exchanger coil or fin, or an aircraft wing, e.g., of an electrified aircraft. The electro-thermal multilayer may be adhered to the component as a coating or removably secured to the component as a module.

Abstract: A coated substrate that may exhibit anti-scaling properties includes a substrate comprising a metal or alloy, an intermediary layer formed on the substrate, and a non-crosslinked omniphobic coating formed on the intermediary layer. A method of forming an anti-scaling coating on a substrate includes forming an intermediary layer on a substrate comprising a metal or alloy, and forming a non-crosslinked omniphobic coating on the intermediary layer.

Abstract: An apparatus for fabricating a hybrid tube includes a rotatable mandrel and a first housing configured to translate alongside the rotatable mandrel while dispensing a first strip to be helically wound about the mandrel. The first housing includes an angle adjustment mechanism to control a dispensation angle of the first strip. The apparatus also includes least one energy or adhesive source for bonding overlapping strip portions on the rotatable mandrel and forming the hybrid tube. The at least one energy or adhesive source is configured for translation alongside the rotatable mandrel.

Abstract: A hydrophobic, self-healing coating includes a vitrimer film having a silicone polymer network crosslinked with dynamic covalent bonds including a boronic ester, where the vitrimer film has a thickness of less than 1000 nm, and where the dynamic covalent bonds provide a mechanism for self-healing of the vitrimer film.

Abstract: A component with a reflective substrate, a photoresist layer disposed on the reflective substrate, and a light diffusing layer sandwiched between the reflective substrate and the photoresist layer is provided. The light diffusing layer includes an outer metal oxide layer with an outer rough surface configured to diffuse laser light during laser interference lithography of the photoresist layer. The outer metal oxide is also configured to be reduced to a conductive metallic layer during electroplating of the substrate. The outer metal oxide layer includes a plurality of elongated light diffusing elements extending in an outward direction from the substrate such that the outer rough surface diffuses at least 90% of laser light during the laser interference lithography of the photoresist layer.

Abstract: A cooling system includes a container having a water-based fluid in which are immersed printed circuit boards (PCBs). One or more high-thermal electrical components are disposed on the PCBs. A condenser causes water vapor generated by the one or more high-thermal electrical components to condense and passively return to the water-based fluid. A nano-engineered coating is deposited over the one or more high-thermal electrical components that includes an electrical insulation coating of between two to 25 microns in thickness deposited on the one or more high-thermal electrical components. A metallic nano-layer comprising a porous metallic nano-structure deposited on the electrical insulation coating.

Abstract: A component with a reflective substrate, a photoresist layer disposed on the reflective substrate, and a light diffusing layer sandwiched between the reflective substrate and the photoresist layer is provided. The light diffusing layer includes an outer metal oxide layer with an outer rough surface configured to diffuse laser light during laser interference lithography of the photoresist layer. The outer metal oxide is also configured to be reduced to a conductive metallic layer during electroplating of the substrate. The outer metal oxide layer includes a plurality of elongated light diffusing elements extending in an outward direction from the substrate such that the outer rough surface diffuses at least 90% of laser light during the laser interference lithography of the photoresist layer.

Abstract: A method includes coating, via chemical vapor deposition, electronics disposed on a printed circuit board (PCB) with an electrical insulation coating of between one micron to 25 microns. The method further include depositing, on the electrical insulation coating, a metallic nano-layer comprising a porous metallic nano-structure. The method further includes, after the coating and the depositing, immersing the PCB in a water-based fluid to cool the electronics while the electronics are powered on.

Abstract: An apparatus includes a printed circuit board (PCB), a power component disposed on the PCB, the power component to generate heat, and a multilayered coating disposed over the power component and at least a portion of the PCB to dissipate heat from the power component, the multilayered including: an electrical insulation layer comprising a non-polar compound and disposed on the power component and the at least a portion of the PCB; a chromium layer disposed on the electrical insulation layer; and a copper layer disposed on the chromium layer that is at least 10 microns (?m) thick, the copper layer conformally adhered to a top of the power component and to the PCB.

Abstract: A porous polymer composite for daytime radiative cooling includes a porous polymer matrix comprising a thermoplastic polymer and including a plurality of pores, and selectively emitting particles dispersed in the porous polymer matrix. When exposed to solar radiation, the porous polymer composite comprises an infrared emissivity of at least about 80% in a wavelength range of 8-13 ?m and/or a solar reflectivity of at least about 80% in a wavelength range of 0.3-2 ?m.

Abstract: A heat and mass transfer component comprises a lubricant-impregnated surface including hydrophobic surface features, which comprise nanostructured surface protrusions having a hydrophobic species attached thereto. The hydrophobic surface features are impregnated with a fluorinated lubricant having a viscosity in a range from about 400 mPa·s to about 6000 mPa·s. A method of fabricating a lubricant-impregnated surface on a heat and mass transfer component comprises: cleaning a thermally conductive substrate to form a cleaned substrate; exposing the cleaned substrate to a hot water or hot alkaline solution to form a thermally conductive substrate having nanostructured surface protrusions; depositing a hydrophobic species on the nanostructured surface protrusions to form hydrophobic surface features; and coating the hydrophobic surface features with a fluorinated lubricant having a viscosity in a range from 400 mPa·s to 6000 mPa·s.

Abstract: A method of achieving high heat transfer during cooling includes providing an aluminum body having an inner surface enclosing a channel, where the inner surface comprises microscale roughness features and microcavities configured to enhance nucleation site density during flow boiling. A refrigerant is transported through the channel. During the transport, the refrigerant absorbs heat from a thermal load and undergoes flow boiling. The heat is transferred to the refrigerant at an average heat transfer coefficient of at least about 10 kW/(m2·K) at a mass flux of about 300 kg/(m2·s).

Abstract: An active thermal management system for electronic devices comprises: a heat spreader having an internal channel; a thermally conductive body moveably positioned in the internal channel; and two or more electronic devices in thermal contact with a back surface of the heat spreader and positioned adjacent to the internal channel. A location of the thermally conductive body within the internal channel determines a path for heat flow from the back surface to a front surface of the heat spreader. The location of the thermally conductive body within the internal channel may be selected to minimize a temperature differential (?T) between the electronic devices.

Abstract: An apparatus for fabricating a hybrid tube includes a rotatable mandrel and a first housing configured to translate alongside the rotatable mandrel while dispensing a first strip to be helically wound about the mandrel. The first housing includes an angle adjustment mechanism to control a dispensation angle of the first strip. The apparatus also includes least one energy or adhesive source for bonding overlapping strip portions on the rotatable mandrel and forming the hybrid tube. The at least one energy or adhesive source is configured for translation alongside the rotatable mandrel.

Abstract: A coated substrate that may exhibit anti-scaling properties includes a substrate comprising a metal or alloy, an intermediary layer formed on the substrate, and a non-crosslinked omniphobic coating formed on the intermediary layer. A method of forming an anti-scaling coating on a substrate includes forming an intermediary layer on a substrate comprising a metal or alloy, and forming a non-crosslinked omniphobic coating on the intermediary layer.

Abstract: A method includes coating, via chemical vapor deposition, electronics disposed on a printed circuit board (PCB) with an electrical insulation coating of between one micron to 25 microns. The method further include depositing, on the electrical insulation coating, a metallic nano-layer comprising a porous metallic nano-structure. The method further includes, after the coating and the depositing, immersing the PCB in a water-based fluid to cool the electronics while the electronics are powered on.

Abstract: A heat and mass transfer component comprises a lubricant-impregnated surface including hydrophobic surface features, which comprise nanostructured surface protrusions having a hydrophobic species attached thereto. The hydrophobic surface features are impregnated with a fluorinated lubricant having a viscosity in a range from about 400 mPa·s to about 6000 mPa·s. A method of fabricating a lubricant-impregnated surface on a heat and mass transfer component comprises: cleaning a thermally conductive substrate to form a cleaned substrate; exposing the cleaned substrate to a hot water or hot alkaline solution to form a thermally conductive substrate having nanostructured surface protrusions; depositing a hydrophobic species on the nanostructured surface protrusions to form hydrophobic surface features; and coating the hydrophobic surface features with a fluorinated lubricant having a viscosity in a range from 400 mPa·s to 6000 mPa·s.

Abstract: A method for coating heat transfer components to impart superhydrophobicity comprises conveying one or more heat transfer components to a cleaning station, where the one or more heat transfer components are cleaned with an organic solvent. After the cleaning, the one or more heat transfer components are conveyed to a nanostructuring station and immersed in hot water for surface oxidation and roughening. After the immersion in hot water, the one or more heat transfer components are conveyed to a functionalization station and exposed to a heated precursor vapor comprising a hydrophobic species. During the exposure, the hydrophobic species is deposited on roughened surfaces of the one or more heat transfer components, thereby forming a superhydrophobic coating. Prior to being conveyed to the cleaning station, the one or more heat transfer components may be attached to an automated conveyor system positioned to traverse the cleaning, nanostructuring, and functionalization stations.