# US 11,029,240 B2 · Wick moisture sensor for airborne particle condensational growth systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,029,240 B2 - Document ID: US11029240B2 - Status: Granted - Kind: B2 - Application number: 16/159,604 - Filed: 2018-10-12 - Published: 2020-04-16 - Granted: 2021-06-08 - Earliest claimed: 2018-10-12 - Assignees: Aerosol Dynamics Inc. - Applicants: Aerosol Dynamics Inc. - Inventors: Susanne Vera Hering; Steven Russel Spielman; Gregory Stephen Lewis - Web page: https://patentgrep.com/patent/US11029240B2 ## CPC - G01N 15/065: {using condensation nuclei counters} - B01D 5/0027: {by direct contact between vapours or gases and the cooling medium} - B01D 5/003: {within column(s)} - B01D 5/0051: {Regulation processes; Control systems, e.g. valves} - F28B 1/02: using water or other liquid as the cooling medium - F28B 11/00: Controlling arrangements with features specially adapted for condensers (control arrangements in general G05) - G01N 21/4738: {Diffuse reflection (precedence is given to G01N21/55 - G01N21/57 if specular component is taken into consideration), e.g. also for testing fluids, fibrous materials} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - 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) - F28B: STEAM OR VAPOUR CONDENSERS (condensation of vapours B01D5/00; steam engine plants having condensers F01K; liquefaction of gases F25J; details of heat-exchange and heat-transfer arrangements of general application F28F) ## Abstract A wick liquid sensor suitable for use in a particle condensation device is provided. The sensor includes a light source configured to illuminate a surface of the wick. A detector is configured to detect wick reflected light from the light source and determine the intensity of reflected light. The wick is formed from a porous media that is wettable by the liquid, and becomes translucent when filled with the liquid. The amount of reflectivity decreases as the saturation content of the liquid in the wick increases. ## Claims ### Claim 1 A wick liquid sensor in a particle condensation system, comprising: a particle growth tube of the particle condensation system containing a wick, the wick comprised of a microporous material which reflects light when dry and becomes translucent as pores in the wick fill with liquid; a light source configured to illuminate a surface of the wick in the growth tube; and a detector configured to detect an intensity of light which is reflected by the wick and determine the intensity of reflected light; the detector is configured to measure an amount of liquid in the wick is based on the intensity of the wick reflected light. ### Claim 2 (depends on 1) The sensor of claim 1 wherein the microporous material is a membrane filter. ### Claim 3 (depends on 1) The sensor of claim 1 wherein the liquid is water or alcohol. ### Claim 4 (depends on 1) The sensor of claim 1 wherein the light source and detector are provided in a housing mounted adjacent to the wick. ### Claim 5 (depends on 1) The sensor of claim 1 further including a light absorbing material positioned opposite the light source and detector below at least one layer of the microporous material. ### Claim 6 (depends on 1) The sensor of claim 1 wherein reflectivity of the wick decreases as saturation content of the liquid in the wick increases. ### Claim 7 A particle condensation system, comprising: a growth tube of the particle condensation system containing a wick, the wick comprised of a microporous material which reflects light when dry and becomes translucent as pores in the wick fills with liquid; a wick sensor configured to determine liquid saturation of the wick, the wick sensor comprising an illumination source positioned to illuminate the wick; a light absorbing material placed under one or more layers of the wick opposite of the illumination source; and a detector configured to measure the saturation of the wick based on an intensity of light which is reflected by the wick. ### Claim 8 (depends on 7) The system of claim 7 wherein the light absorbing material is wettable by the saturating liquid. ### Claim 9 (depends on 8) The system of claim 8 wherein the microporous material is a membrane filter. ### Claim 10 (depends on 8) The system of claim 8 wherein the liquid is water. ### Claim 11 (depends on 8) The sensor of claim 8 wherein the liquid is alcohol. ### Claim 12 (depends on 8) The system of claim 8 wherein an output of the sensor is used as feedback signal to regulate a temperature or other operating parameter of the system. ### Claim 13 A particle condensation system, comprising: a growth tube of the particle condensation system including a wick formed from multiple layers of a microporous material which reflects light when dry and becomes translucent as pores in the wick fill with a liquid; and a wick sensor comprising a light source configured to illuminate a surface of the wick and a detector configured to measure an amount of the liquid in the wick based on a determination of an intensity of light which is reflected by the wick. ### Claim 14 (depends on 13) The system of claim 13 further including a light absorbing material placed under one or more layers of the wick opposite of the illumination source. ### Claim 15 (depends on 13) The particle condensation system of claim 13 further including a tube inlet and a tube outlet, the system including a humidification system at the inlet. ### Claim 16 (depends on 15) The particle condensation system of claim 15 where the humidification system uses a hygroscopic material. ### Claim 17 (depends on 13) The system of claim 13 wherein the tube has a first section, a second section and a third section though which air flows between an inlet and an outlet, a temperature of the second section is warmer than that of the first section at the inlet and the third section at the outlet, wherein the sensor is provided in a housing between the second section and the third section. ### Claim 18 (depends on 13) The system of claim 13 wherein reflectivity of the wick increases as the wick dries. ### Claim 19 (depends on 13) The system of claim 13 wherein the light source and detector are provided in a housing mounted adjacent to the wick. ### Claim 20 (depends on 13) The system of claim 13 wherein an output of the sensor is used as feedback signal to regulate a temperature or other operating parameter of the system.