Amphiphilic minichannel surface structures to enhance heat transfer coefficient
A structure for enhancing condensation and wetting dynamics includes a substrate and a channel formed in the substrate, forming fins. The fins have a hydrophilic surface. Each of the fins has a portion furthest from the substrate. A hydrophobic coating is formed over only the portion furthest from the substrate on each of the fins.
1 . A structure for enhancing condensation and wetting dynamics comprising:
a tubular substrate;
a channel formed in the substrate, forming fins, having a hydrophilic surface, each of the fins having a portion furthest from the substrate; and
a hydrophobic coating over only the portion furthest from the substrate on each of the fins.
2 . The structure according to claim 1 , wherein the substrate comprises aluminum.
3 . The structure according to claim 1 , wherein the channel has a helical shape.
4 . The structure according to claim 1 , wherein the coating comprises rubber.
5 . The structure according to claim 1 , wherein, when a ratio of the height of each fin below the coating versus the distance between adjacent fins is between about 0.1 and about 10.
6 . The structure according to claim 1 , wherein the thickness of the coating is between about 0.1 and about 200 microns.
7 . The structure according to claim 1 , wherein a ratio of the height of each of the fins versus a height of each of the portion furthest from the substrate hang a hydrophobic coating is between about 0.01 and about 0.99.
8 . A structure for enhancing condensation and wetting dynamics comprising:
a substrate;
a plurality of grooves in the substrate, forming a plurality of fins, the plurality of fins extending away from the substrate, each of the plurality of fins having a hydrophilic surface, each of the fins having a coating formed only on a coated portion furthest from the substrate.
9 . The structure according to claim 8 , wherein the coating comprises silicone rubber.
10 . The structure according to claim 8 , wherein the coating has a lower thermal conductivity than the substrate.
11 . The structure according to claim 8 , wherein the coating has a thickness of between 0.1 microns and 200 microns.
12 . A structure for enhancing condensation and wetting dynamics comprising:
a tubular substrate;
a plurality of grooves in the substrate, forming a plurality of fins, the plurality of fins extending outwardly from the tubular substrate, each of the plurality of fins having:
an attached portion; and
a free portion, distal from the attached portion,
wherein each of the plurality of fins has a hydrophilic surface; and
a coating on only the free portion of each of the plurality of fins.