Systems and methods that utilize enhanced boiling surfaces to promote the efficiency of boiling. Such a system has a surface that is hydrophobic and exhibits a sufficiently low receding contact angle to a liquid such that vapor spreading during bubble growth and premature transition to film boiling is mitigated.

A metal heat exchanger tube has integral ribs formed on the outside of the tube. The ribs have a rib base, rib flanks, and a rib tip. The rib base protrudes substantially radially from the tube wall. A channel is formed between the ribs, in which channel additional structures spaced apart from each other are arranged. The additional structures divide the channel between the ribs into segments. The additional structures reduce the cross-sectional area in the channel between two ribs through which flow is possible by at least 60% locally and, at least thereby, limit a fluid flow in the channel during operation.

A heat transfer system includes a substrate having a heat exchange region including a surface having an enhancement region including alternating regions of selectively placed plurality of nucleation sites and regions lacking selectively placed nucleation sites, such that bubble formation and departure during boiling of a liquid in contact with the enhancement region induces liquid motion over the surface of the regions lacking selectively placed nucleation sites sufficient to enhance both critical heat flux and heat transfer coefficient at the critical heat flux in the enhancement region of the system.

A method and apparatus for pool boiling includes introducing a fluid into a chamber of a housing which has one or more protruding features. One or more diverters extend at least partially across the one or more protruding features in the chamber. One or more bubbles are formed in the fluid in the chamber as a result of bubble nucleation. At least one of growth and motion of the one or more of the bubbles are diverted with the one or more diverters to generate additional localized motion of the fluid along at least one of the one or more protruding features and other surfaces in the chamber of the housing to at least of transfer additional heat to the liquid and increase the critical heal flux limit.

In embodiments, a heat exchanger includes a tube configured to transfer a first fluid. The tube includes an outer surface configured to exchange heat with a second fluid as the second fluid flows over the outer surface of the tube. The tube also includes an inner surface defining an interior configured to contain and transfer the first fluid, and a plurality of surface features integrally formed as part of the inner surface. The surface features may extend radially inward toward the interior, and are configured to increase a surface area of the inner surface to improve heat exchange between the tube and the first fluid.

A heat transfer system includes a steam chamber that communicates in an open-loop arrangement with a first steam source for supplying steam to the steam chamber, the steam chamber including a steam exit for supplying steam to air at atmospheric pressure. A heat transfer tube communicates in a closed-loop arrangement with a second steam source for supplying steam to an interior surface of the heat transfer tube, the heat transfer tube vaporizing condensate forming within the heat transfer system back to steam that is supplied to the air via the steam exit. The outer surface of the heat transfer tube is configured to contact the condensate and vaporize the condensate back into steam, wherein the heat transfer tube includes a plurality of pockets formed on the outer surface of the tube, each pocket including a pocket exit/entry portion having a smaller cross-sectional area than the cross-sectional area of the pocket at a root portion thereof adjacent the outer surface of the tube.

A thermal energy exchange tube for a heat exchanger includes a tube inner surface and a tube outer surface radially offset from the tube inner surface. The tube outer surface includes patterned porosity with a plurality of high porosity regions of the tube outer surface having relatively high porosity to promote flow of fluid radially inwardly via capillary flow, and a plurality of low porosity regions of the tube outer surface having relatively low porosity to facilitate vapor departure from the tube outer surface.

The invention relates to a mechanical vapour compression (MVC) desalination arrangement having a low compression ratio, with latent-heat exchangers having a high latent-heat exchange coefficient, with a temperature gradient between primary vapour and secondary vapour of approximately 1° C. or less, a compression ratio of 1.11 or less, high vapour volume, low overheating and a low-temperature saline solution to be desalinated, which arrangement allows industrial desalination with less specific energy per unit of desalinated water and is coupled to 100% renewable off-grid energy sources.

A method of forming a textured surface layer along a substrate that includes disposing a plurality of polymer spheres on a surface of the metal substrate, and electroplating the metal substrate at a current density to deposit a metal layer along a body of each of the plurality of polymer spheres disposed on the surface of the metal substrate. The metal layer does not extend above a top surface of the plurality of polymer spheres. The method further includes removing the plurality of polymer spheres from the metal layer to form the textured surface defined by a size and shape of the plurality of polymer spheres.

A cycling heat dissipation module suited for dissipating heat generated from a heat source is provided. The cycling heat dissipation module includes an evaporator, a condenser, and a micro/nano-structure. The evaporator is thermal contacted with the heat source to absorb heat generated therefrom. The condenser is connected to the evaporator to form a loop, and a working fluid is filled in the loop. The working fluid in liquid state is transformed to vapor state by absorbing heat in the evaporator, and the working fluid in vapor state is transformed to liquid state by dissipating heat in the condenser. The micro/nano-structure is disposed in the condenser to destroy a boundary layer of the working fluid while passing through the condenser.