Patents by Inventor Rengasamy Ponnappan

Rengasamy Ponnappan 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).

  • Patent number: 6293333
    Abstract: A micro channel heat pipe and method of fabrication are disclosed. The micro channel heat pipe includes a wire cloth wick having micro capillary channels formed by a corrugation extrusion process. The wick is inserted into the heat pipe housing in a shrink fit, enhancing heat transfer. The porous nature of the wire cloth wick permits free passage of the working fluid within both the closed and open micro capillary channels, doubling the number of micro capillary channels available for heat transference.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: September 25, 2001
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Rengasamy Ponnappan, John E. Leland
  • Patent number: 6294853
    Abstract: A passively cooled electromechanical actuator is disclosed. The passively cooled electromechanical actuator includes a rotor having an output shaft rotatably received within a stator. A pair of inner supports connect the stator to a pair of mounting platforms. The mounting platforms are attached to the inner surfaces of an aircraft wing and are in thermal communication therewith. A pair of closed, capillary tube thermosyphons containing a working fluid are in thermal communication with the stator, the inner supports and the mounting platforms. During operation, the thermosyphons receive heat from the stator and transport it to the mounting platforms whereupon it is convected or radiated to the atmosphere from the aircraft wings. The inner supports have a phase change material received within for providing temporary thermal energy storage during transient conditions.
    Type: Grant
    Filed: November 2, 2000
    Date of Patent: September 25, 2001
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Lanchao Lin, John E. Leland, Rengasamy Ponnappan
  • Patent number: 6216343
    Abstract: A corrugated fin heat pipe and method of fabrication. The micro channel heat pipe includes a tubular housing split longitudinally into two halves. A pair of corrugated fin elements defining a plurality of adjacent closed and open micro capillary channels are attached to the inner surface of the housing halves. Material is removed from the closed micro capillary channels along a portion of the longitudinal axis to create regions consisting entirely of open micro capillary channels, maximizing heat flux in those regions. The housing halves are reattached and the heat pipe housing is enclosed by a pair of end caps.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: April 17, 2001
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: John E. Leland, Rengasamy Ponnappan
  • Patent number: 5629573
    Abstract: A new system for removing heat energy from the rotor of a rotating electrical machine is disclosed. Rotating electrical machines include electric motors, electric generators and the like. The cooling system includes the prior art components of an integral heat pipe rotor shaft, that is, a hollow rotor shaft in which an inner cavity is filled with a suitable working fluid to make an integral heat pipe for removing heat from the rotor. The heat pipe includes an evaporator section inside the rotor and a condenser section extending outside the rotor and the electrical machine housing. The present invention adds a spray chamber surrounding the condenser section. The spray chamber is integrated with the electrical machine housing. Liquid coolant enters the spray chamber and is sprayed through nozzles onto the condenser section to remove the heat transferred from the rotor. The liquid coolant may be routed through a preheater before entering the spray chamber.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: May 13, 1997
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Rengasamy Ponnappan, Jerry E. Beam, John E. Leland
  • Patent number: 5283488
    Abstract: A rotor structure for an electrical generator, motor or the like is described which comprises a rotatable generally cylindrically shaped heat pipe defining an internal vapor chamber having an evaporator end and a condenser end, a plurality of radial fins regularly spaced on the periphery of the heat pipe, each fin defining an internal chamber communicating with and extending radially from the vapor chamber, a vaporizable liquid disposed within said heat pipe, and a heat exchanger in thermal contact with the condenser end of the heat pipe.
    Type: Grant
    Filed: February 22, 1993
    Date of Patent: February 1, 1994
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Rengasamy Ponnappan, Jerry E. Beam