Patents by Inventor Kripa K. Varanasi

Kripa K. Varanasi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20130340840
    Abstract: Methods described herein provide a way to reduce or eliminate drag and adhesion of a substance flowing over a surface by creating a vapor cushion via evaporation of a phase-changing material of or on the surface or encapsulated within textures of the surface. The vapor cushion causes the flowing substance to be suspended over the surface, greatly reducing friction, drag, and adhesion between the flowing substance and the surface. The temperature of the flowing substance is above the sublimation point and/or melting point of the phase-changing material. The phase-changing material undergoes a phase change (evaporation or sublimation) upon contact with the flowing substance due to local heat transfer from the flowing substance to the material, generating a vapor cushion between the solid or liquid material and the flowing substance.
    Type: Application
    Filed: June 13, 2013
    Publication date: December 26, 2013
    Inventors: Sushant Anand, Kripa K. Varanasi
  • Publication number: 20130337027
    Abstract: Described herein are medical devices and medical implements with high lubricity to flesh (or biological fluid) and/or inhibited nucleation on its surface. The device has a surface comprising an impregnating liquid and a plurality of micro-scale and/or nano-scale solid features spaced sufficiently close to stably contain the impregnating liquid therebetween. The impregnating liquid fills spaces between said solid features, the surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially held in place between the plurality of solid features regardless of orientation of the surface.
    Type: Application
    Filed: May 24, 2013
    Publication date: December 19, 2013
    Applicant: Massachusetts Institute of Technology
    Inventors: J. David Smith, Rajeev Dhiman, Adam T. Paxson, Christopher J. Love, Brian R. Solomon, Kripa K. Varanasi
  • Publication number: 20130333789
    Abstract: Described herein are conduits for conveying fluids and/or solids, the conduits having an interior surface that provide a high-slip boundary condition, thereby facilitating the flow of material therethrough. In some embodiments, the conduit has an interior surface with an impregnating liquid and a plurality of micro-scale and/or nano-scale solid features spaced sufficiently close to stably contain the impregnating liquid therebetween. The impregnating liquid fills spaces between the solid features, the interior surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially held in place between the plurality of solid features regardless of orientation of the interior surface and regardless of flow, passage, or removal of fluids and/or solids through, into, or out of the conduit.
    Type: Application
    Filed: May 24, 2013
    Publication date: December 19, 2013
    Applicant: Massachusetts Institute of Technology
    Inventors: J. David Smith, Rajeev Dhiman, Adam T. Paxson, Christopher J. Love, Brian R. Solomon, Kripa K. Varanasi
  • Publication number: 20130335697
    Abstract: Described herein is a contact lens with high lubricity to eye tissue/fluid and inhibited nucleation on its surface. The contact lens has a surface textured to form a matrix of micro-scale and/or nano-scale solid (e.g., gel) features spaced sufficiently close to stably contain an impregnating liquid therebetween. The impregnating liquid fills spaces between the solid features, the surface stably contains the impregnating liquid between the solid features, and the impregnating liquid is substantially held in place between the plurality of solid features regardless of orientation of the surface and despite contact with the eye tissue during normal wear, insertion, and removal of the contact lens.
    Type: Application
    Filed: May 24, 2013
    Publication date: December 19, 2013
    Inventors: J. David Smith, Rajeev Dhiman, Adam T. Paxson, Christopher J. Love, Brian R. Solomon, Kripa K. Varanasi
  • Patent number: 8574704
    Abstract: The invention is directed to an article with a liquid-impregnated surface, the surface having a matrix of features thereupon, spaced sufficiently close to stably contain a liquid therebetween or therewithin, and preferable also a thin film thereupon. The surface provides the article with advantageous non-wetting properties. Compared to previous non-wetting surfaces, which include a gas (e.g., air) entrained within surface textures, these liquid-impregnated surfaces are resistant to impalement and frost formation, and are therefore more robust.
    Type: Grant
    Filed: August 16, 2012
    Date of Patent: November 5, 2013
    Assignee: Massachusetts Institute of Technology
    Inventors: J. David Smith, Rajeev Dhiman, Kripa K. Varanasi, Ernesto Reza-Garduño Cabello
  • Publication number: 20130251942
    Abstract: This invention relates generally to an article that includes a base substrate and a hydrophobic coating on the base substrate, wherein the hydrophobic coating includes a rare earth element material (e.g., a rare earth oxide, a rare earth carbide, a rare earth nitride, a rare earth fluoride, and/or a rare earth boride). An exposed surface of the hydrophobic coating has a dynamic contact angle with water of at least about 90 degrees. A method of manufacturing the article includes providing the base substrate and forming a coating on the base substrate (e.g., through sintering or sputtering).
    Type: Application
    Filed: March 23, 2012
    Publication date: September 26, 2013
    Inventors: Gisele Azimi, Kripa K. Varanasi, Rajeev Dhiman, Adam T. Paxson, Kyukmin Kwon
  • Publication number: 20130251952
    Abstract: In certain embodiments, the invention relates to an article having a liquid-impregnated surface. The surface includes a matrix of solid features (e.g., non-toxic and/or edible features) spaced sufficiently close to stably contain a liquid therebetween or therewithin, wherein the liquid is non-toxic and/or edible. The article may contain, for example, a food or other consumer product, such as ketchup, mustard, or mayonnaise.
    Type: Application
    Filed: June 13, 2012
    Publication date: September 26, 2013
    Applicant: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
    Inventors: Jonathan David Smith, Rajeev Dhiman, Adam T. Paxson, Christopher J. Love, Brian R. Solomon, Kripa K. Varanasi
  • Publication number: 20130251769
    Abstract: In certain embodiments, the invention relates to an article having a liquid-impregnated surface. The surface includes a matrix of solid features (e.g., non-toxic and/or edible features) spaced sufficiently close to stably contain a liquid therebetween or therewithin, wherein the liquid is non-toxic and/or edible. The article may contain, for example, a food or other consumer product, such as ketchup, mustard, or mayonnaise.
    Type: Application
    Filed: July 17, 2012
    Publication date: September 26, 2013
    Applicant: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
    Inventors: Jonathan David Smith, Rajeev Dhiman, Adam T. Paxson, Christopher J. Love, Brian R. Solomon, Kripa K. Varanasi
  • Patent number: 8535779
    Abstract: In certain embodiments, the invention relates to an article having a liquid-impregnated surface. The surface includes a matrix of solid features (e.g., non-toxic and/or edible features) spaced sufficiently close to stably contain a liquid therebetween or therewithin, wherein the liquid is non-toxic and/or edible. The article may contain, for example, a food or other consumer product, such as ketchup, mustard, or mayonnaise.
    Type: Grant
    Filed: July 17, 2012
    Date of Patent: September 17, 2013
    Assignee: Massachusetts Institute of Technology
    Inventors: Jonathan David Smith, Rajeev Dhiman, Adam T. Paxson, Christopher J. Love, Brian R. Solomon, Kripa K. Varanasi
  • Publication number: 20130220813
    Abstract: The articles and methods described herein provide a way to manipulate condensation on a surface by micro/nano-engineering textures on the surface and filling the spaces between the texture features with an impregnating liquid that is stably held therebetween or therewithin. The articles and methods allow droplets of water, or other condensed phases, even in micrometer size range, to easily shed from the surface, thereby enhancing contact between a condensing species and the condensing surface. It has been found that dropwise condensation is enhanced by the use of an impregnating (secondary) liquid that has a relatively high surface tension, and, even more preferably, an impregnating liquid that has both a high surface tension and a low viscosity.
    Type: Application
    Filed: June 13, 2012
    Publication date: August 29, 2013
    Applicant: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
    Inventors: Sushant Anand, Adam T. Paxson, Jonathan David Smith, Kripa K. Varanasi
  • Publication number: 20130032646
    Abstract: This invention relates generally to an article that includes a non-wetting surface having a dynamic contact angle of at least about 90°. The surface is patterned with macro-scale features configured to induce controlled asymmetry in a liquid film produced by impingement of a droplet onto the surface, thereby reducing time of contact between the droplet and the surface.
    Type: Application
    Filed: November 18, 2011
    Publication date: February 7, 2013
    Inventors: Rajeev Dhiman, James C. Bird, Hyukmin Kwon, Kripa K. Varanasi
  • Publication number: 20130034695
    Abstract: The invention is directed to an article with a liquid-impregnated surface, the surface having a matrix of features thereupon, spaced sufficiently close to stably contain a liquid therebetween or therewithin, and preferable also a thin film thereupon. The surface provides the article with advantageous non-wetting properties. Compared to previous non-wetting surfaces, which include a gas (e.g., air) entrained within surface textures, these liquid-impregnated surfaces are resistant to impalement and frost formation, and are therefore more robust.
    Type: Application
    Filed: August 16, 2012
    Publication date: February 7, 2013
    Applicant: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
    Inventors: J. David Smith, Rajeev Dhiman, Kripa K. Varanasi, Ernesto Reza-Garduño Cabello
  • Publication number: 20130032316
    Abstract: The invention is directed to an article with a liquid-impregnated surface, the surface having a matrix of features thereupon, spaced sufficiently close to stably contain a liquid therebetween or therewithin, and preferable also a thin film thereupon. The surface provides the article with advantageous non-wetting properties. Compared to previous non-wetting surfaces, which include a gas (e.g., air) entrained within surface textures, these liquid-impregnated surfaces are resistant to impalement and frost formation, and are therefore more robust.
    Type: Application
    Filed: November 22, 2011
    Publication date: February 7, 2013
    Inventors: Rajeev Dhiman, J. David Smith, Kripa K. Varanasi, Ernesto Reza-Garduño Cabello
  • Publication number: 20120201759
    Abstract: Hierarchical nanostructures and methods of fabrication. The structures include particles having a metal oxide outer shell with metal oxide wires extending from the outer shell. A multiscale structure according to the invention has particles above and below a critical size wherein the particles above the critical size have wires extending from the surface. These structures may be fabricated from a mixture prepared of relatively smaller metal particles having a size threshold below a threshold for nanowire formation and of relatively larger metal particles having a size above the threshold for nanowire formation. The mixture is oxidized at a selected temperature and for a selected time whereby the relatively smaller particles sinter and nanowires grow on the relatively larger particles thereby creating tunable hierarchical structures with metal-to-metal contact between the particles.
    Type: Application
    Filed: February 1, 2012
    Publication date: August 9, 2012
    Applicant: Massachusetts Institute of Technology
    Inventors: Christopher Jameson Love, J. David Smith, Kripa K. Varanasi
  • Publication number: 20120160362
    Abstract: This invention relates generally to articles, devices, and methods for gas hydrate mitigation in deep-sea drilling applications. In certain embodiments, hydrate-phobic surfaces are provided that ensure passive enhancement of flow assurance and prevention of catastrophic failures in deep-sea oil and gas operations.
    Type: Application
    Filed: August 25, 2011
    Publication date: June 28, 2012
    Applicant: Massachusetts Institute of Technology
    Inventors: J. David Smith, Kripa K. Varanasi, Gareth H. McKinley, Robert E. Cohen, Adam J. Meuler, Harrison L. Bralower
  • Publication number: 20120142795
    Abstract: Method for treating thermoplastic to make a surface thereof superhydrophobic. The method includes exposing the thermoplastic to a specific solvent for a selected time period. It is preferred that the treatment time be in the range of one minute to approximately five hours and more preferably in the range of one minute to 15 minutes. Thermoplastics and solvents having a similar solubility parameter interact with one another to form hydrophobic hierarchical surfaces.
    Type: Application
    Filed: December 6, 2010
    Publication date: June 7, 2012
    Applicant: Massachusetts Institute of Technology
    Inventors: Kripa K. Varanasi, Adam T. Paxson, Katherine M. Smyth, Yuehua Cui
  • Publication number: 20120103456
    Abstract: This invention relates generally to articles, devices, and methods for gas hydrate mitigation in deep-sea drilling applications. In certain embodiments, hydrate-phobic surfaces are provided that ensure passive enhancement of flow assurance and prevention of catastrophic failures in deep-sea oil and gas operations.
    Type: Application
    Filed: August 25, 2011
    Publication date: May 3, 2012
    Applicant: Massachusetts Institute of Technology
    Inventors: J. David Smith, Kripa K. Varanasi
  • Publication number: 20120051489
    Abstract: Textured surface for increasing Leidenfrost temperature. The texture comprises of surface features over multiple length scales—from micro to nanoscale—wherein the features at each length scale have a size, aspect ratio, and spacing selected to increase the Leidenfrost temperature. The structure includes an array of microscale structures disposed on the surface, the structure having size, aspect ratio and spacing selected to increase Leidenfrost temperature. The microscale structures may also include nanoscale structures on their surface to create a hierarchical structure. The structures result in an increased Leidenfrost temperature.
    Type: Application
    Filed: August 31, 2010
    Publication date: March 1, 2012
    Applicant: Massachusetts Institute of Technology
    Inventors: Kripa K. Varanasi, Jonathan D. Smith, Adam T. Paxson, Christopher J. Love, Hyukmin Kwon, Dieter B. Brommer
  • Publication number: 20090033037
    Abstract: A seal assembly comprising a first movable stator member movable between a sealing position and a non-sealing position, a second fixed stator member, the first stator member being movable relative to the second stator member, the seal assembly further comprising at least one flexure member coupled to the second stator member, and at least one biasing member coupled between the at least one flexure and the movable stator for biasing the movable stator to a non-sealing position.
    Type: Application
    Filed: July 30, 2007
    Publication date: February 5, 2009
    Inventors: Kripa K. Varanasi, Joseph C. Albers, William L. Herron, Peter Crudgington