# US 2014/0190352 A1 · Liquid collecting permeable structures > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0190352 A1 - Document ID: US20140190352A1 - Status: Published application - Kind: A1 - Application number: 14/152,432 - Filed: 2014-01-10 - Published: 2014-07-10 - Earliest claimed: 2013-01-10 - Assignees: Massachusetts Institute of Technology - Applicants: Massachusetts Institute of Technology - Inventors: Kyoo-Chul Park; Shreerang S. Chhatre; Gareth H. McKinley; Robert E. Cohen - Web page: https://patentgrep.com/patent/US20140190352A1 ## CPC - B01D 39/083: {of organic material} - B01D 2239/0428: Rendering the filter material hydrophobic - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract A structure for collecting liquid droplets from an aerosol can have a structure and properties that are selected for efficient liquid collection. In particular, the strand radius and spacing of a mesh, and a material for coating the mesh, can be selected to provide efficient collection of water droplets from fog. ## Claims ### Claim 1 A device for collecting droplets of a liquid from an aerosol, comprising: an aerosol-permeable structure including strands having a characteristic radius, and a characteristic spacing, a characteristic spacing ratio; wherein the outermost surface of the strands comprises a material having a low contact angle hysteresis for the liquid. ### Claim 2 (depends on 1) The device of claim 1, wherein the material and the characteristic spacing are selected such that liquid droplets adhered to the structure will drain from the structure under gravity. ### Claim 3 (depends on 1) The device of claim 1, wherein the characteristic radius is R, the characteristic spacing is 2D, and the spacing ratio is D*=(R+D)/R, and the radius and the spacing are selected such that 2≦D*≦4. ### Claim 4 (depends on 1) The device of claim 1, wherein the spacing is selected such that r e ≈ 4  πγ lv  sin 2  θ  ( 1 + cos   θ rec ) ρ air  v 0 2  C D  ( θ - sin   θ   cos   θ ) where γLV is the surface tension of the liquid, θ=(θadv+θrec)/2 is the mean contact angle of the droplet on the surface, and θadv, θrec are the advancing contact angle and receding contact angle, respectively, and r c ≈ 12  γ lv  ( cos   θ rec - cos   θ adv ) πρ water  gB  ( 3 + B 2 ) ( 3 ) where B=(1−cos θ)/sin θ, ρ is the density of the liquid, and g is the gravitational constant. ### Claim 5 (depends on 1) The device of claim 1, wherein the liquid is water. ### Claim 6 (depends on 1) The device of claim 1, wherein the material is a hydrophobic material. ### Claim 7 (depends on 1) The device of claim 1, wherein the structure is a woven mesh. ### Claim 8 (depends on 1) The device of claim 1, wherein the material includes a polyhedral oligomeric silsesquioxane (POSS) and a poly(acrylate). ### Claim 9 (depends on 1) The device of claim 1, wherein the polyhedral oligomeric silsesquioxane (POSS) is a fluorinated polyhedral oligomeric silsesquioxane, and the poly(acrylate) is poly(methyl methacrylate), poly(ethyl methacrylate), or a combination thereof. ### Claim 10 (depends on 1) A method for collecting droplets of a liquid from an aerosol, comprising: providing a device according to claim 1; and contacting an aerosol including droplets of the liquid with the structure. ### Claim 11 (depends on 10) The method of claim 10, wherein the aerosol is fog. ### Claim 12 (depends on 10) The method of claim 10, further comprising providing a second device downwind of the first device. ### Claim 13 A method of making a device for collecting droplets of a liquid from an aerosol, comprising: identifying aerosol conditions, wherein the conditions include an average droplet size of the aerosol and a wind velocity of the aerosol; selecting a characteristic radius, a characteristic spacing, and a characteristic spacing for strands of an aerosol-permeable structure, so as to provide efficient droplet collection for the identified conditions; selecting a material having a low contact angle hysteresis for the liquid; and applying the material to form the outermost surface of the strands. ### Claim 14 (depends on 13) The method of claim 13, wherein the material and the characteristic spacing are selected such that liquid droplets adhered to the structure will drain from the structure under gravity. ### Claim 15 (depends on 13) The method of claim 13, wherein the characteristic radius is R, the characteristic spacing is 2D, and the spacing ratio is D*=(R+D)/R, and the radius and the spacing are selected such that 2≦D*≦4. ### Claim 16 (depends on 13) The method of claim 13, wherein the spacing is selected such that r e ≈ 4  πγ lv  sin 2  θ  ( 1 + cos   θ rec ) ρ air  v 0 2  C D  ( θ - sin   θcosθ ) where γLV is the surface tension of the liquid, θ=(θadv+θrec)/2 is the mean contact angle of the droplet on the surface, and θadv, θrec are the advancing contact angle and receding contact angle, respectively, and r c ≈ 12  γ lv  ( cos   θ rec - cos   θ adv ) πρ water  gB  ( 3 + B 2 ) ( 3 ) where B=(1−cos θ)/sin θ, ρ is the density of the liquid, and g is the gravitational constant. ### Claim 17 (depends on 13) The method of claim 13, wherein the liquid is water. ### Claim 18 (depends on 13) The method of claim 13, wherein the material is a hydrophobic material. ### Claim 19 (depends on 13) The method of claim 13, wherein the structure is a woven mesh. ### Claim 20 (depends on 13) The method of claim 13, wherein the material includes a polyhedral oligomeric silsesquioxane (POSS) and a poly(acrylate). ### Claim 21 (depends on 13) The method of claim 13, wherein the polyhedral oligomeric silsesquioxane (POSS) is a fluorinated polyhedral oligomeric silsesquioxane, and the poly(acrylate) is poly(methyl methacrylate), poly(ethyl methacrylate), or a combination thereof.