Coatings for enhancing performance of materials surfaces, methods of producing the coating and coated substrates, and coated condensers are disclosed herein. More particularly, exemplary embodiments provide chemical coating materials useful for coating condenser components.

The present invention relates to a method of enhancing heat transfer of metallic surfaces by (1) fabricating hierarchical micro-nanostructured surfaces using etching processes, and (2) fabricating hydrophobic and hydrophilic regions, using a printing or a coating technique, followed by etching. The said method enhances the density of condensation sites over a metallic surface and additionally facilitates the departure of condensed droplets from the surface. Such a surface also enhances the sensible heat transfer characteristics, and improves the coefficient of performance (COP) of refrigeration systems for applications like atmospheric water generators, dehumidifiers, air conditioners, etc.

A total heat exchange element includes partitions disposed in a state of being opposed to each other, and a spacer portion keeping a space between the partitions and forming a passage between the partitions. The spacer portion has a laminate structure in which nonwoven fabric base layers including a nonwoven fabric base material are laminated on both sides of a paper layer. A first nonwoven fabric base layer that is the nonwoven fabric base layer of the spacer portion laminated on one side of the paper layer is joined to the partition opposed to the first nonwoven fabric base layer, and a second nonwoven fabric base layer that is the nonwoven fabric base layer of the spacer portion laminated on another side thereof is joined to the partition opposed to the second nonwoven fabric base layer. The element has the above-mentioned configuration and so can improve the humidity exchange efficiency.

Provided is a heat exchanger capable of ensuring both heat exchange performance and reliability against corrosion. The heat exchanger includes a plurality of fins each having a flat plate shape, openings provided in each of the plurality of fins, and cylindrical parts arranged on outer peripheries of the openings, each having an inner diameter larger than an outer diameter of each of the openings. The plurality of fins are stacked on one another with the cylindrical parts interposed between the plurality of fins. The openings and the cylindrical parts are configured to form a liquid passage pipe, and the openings protrude further inside than are the cylindrical parts.

A high efficiency heat sink for the cooling of microelectronic devices involves a phase change from liquid fluid to fluid vapor with a vapor quality of 100%. The liquid fluid is provided to an active area that contains fins having micrometer dimension that support a membrane that is nanoporous. The membrane is effectively impermeable to liquid fluid but permeable to fluid vapor. The heat sink provides very high heat flux and coefficient of heat transfer at low mass flux over a broad range of surface superheat temperatures. The heat sink can be constructed of equi-spaced posts that separate liquid microchannels from vapor microchannels that are connected through capillary forced valves formed between adjacent equi-spaced posts.

Phase change material modules for use in a heat exchanger are described. The phase change material module comprises two or more set of a plurality of substantially aligned hollow structures arranged to form a porous structure. A phase change material capable of undergoing a phase change as a result of heat exchange between it and a fluid is housed within the hollow tubes. Also described is a phase change material module with hollow tubes having a cross-sectional area through the phase change material selected from elliptical, rectangular, stadium-shaped, teardrop-shaped, airfoil-shaped, rounded rectangle and ovoid. A heat exchanger comprising a plurality of the phase change material modules, a first fluid inlet and outlet, and a second fluid inlet and outlet, wherein the phase change material modules are repeated circulated from alignment with the first fluid inlet and the second fluid inlet is also described.

A heat dissipation device includes two titanium metal sheets, which are subjected to a heat treatment before undergoing mechanical processing, plastic working and surface modification. With these arrangements, the titanium metal sheets can be freely plastically deformed and possess a capillary force, and can therefore be used in place of the conventional copper material to serve as a material for making heat dissipation devices, and the heat dissipation devices so produced can have largely reduced weight and largely improved heat dissipation performance.

In certain embodiments, the invention is directed to apparatus comprising a liquid-impregnated surface, said surface comprising an impregnating liquid and a matrix of solid features spaced sufficiently close to stably contain the impregnating liquid therebetween or therewithin, and methods thereof. In some embodiments, one or both of the following holds: (i) 0<0.25, where is a representative fraction of the projected surface area of the liquid-impregnated surface corresponding to non-submerged solid at equilibrium; and (ii) S.sub.ow(a)<0, where S.sub.ow(a) is spreading coefficient, defined as .sub.wa.sub.wo.sub.oa, where is the interfacial tension between the two phases designated by subscripts w, a, and o, where w is water, a is air, and o is the impregnating liquid.

A system for coating a heat transfer tube for a condenser is disclosed. The system simplifies a process of coating the heat transfer tube, and is able to uniformly coat a plurality of heat transfer tubes. In addition, the system is economically feasible in that coating solution can be reused by collecting and circulating it. Due to super-hydrophobic coating, the size of a droplet condensed on the surfaces of the heat transfer tubes coated by the system can be reduced, and a condensation heat transfer coefficient can be increased.

A two-phase microchannel heat sink can be a fluid channel including a bottom wall including a superhydrophilic surface with microstructures and a side wall including a surface that is hydrophobic relative to the superhydrophilic surface of the bottom wall. When heat flux is applied to the fluid channel, a liquid film on the bottom wall is maintained and nucleation of boiling occurs only on the side wall.