Alan Jay Epstein

US Patent:

6392313, May 21, 2002

Filed:

Jul 15, 1999

Appl. No.:

09/354544

Inventors:

Alan H. Epstein - Lexington MA
Stephen D. Senturia - Brookline MA
Ian A. Waitz - Newton MA
Jeffrey H. Lang - Sudbury MA
Stuart A. Jacobson - Somerville MA
Fredric F. Ehrich - Marblehead MA
Martin A. Schmidt - Reading MA
G. K. Ananthasuresh - Philadelphia PA
Mark S. Spearing - Newton MA
Kenneth S. Breuer - Newton MA
Steven F. Nagle - Cambridge MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H01L 2984

US Classification:

290 52, 310 40 MM, 60 3936, 257414

Abstract:

The invention overcomes limitations of conventional power and thermodynamic sources by with micromachinery components that enable production of significant power and efficient operation of thermodynamic systems in the millimeter and micron regime to meet the efficiency, mobility, modularity, weight, and cost requirements of many modern applications. A micromachine of the invention has a rotor disk journalled for rotation in a stationary structure by a journal bearing. A plurality of radial flow rotor blades, substantially untapered in height, are disposed on a first rotor disk face, and an electrically conducting region is disposed on a rotor disk face. A plurality of stator electrodes that are electrically interconnected to define multiple electrical stator phases are disposed on a wall of the stationary structure located opposite the electrically conducting region of the rotor disk. A first orifice in the stationary structure provides fluidic communication with the first rotor disk face at a location radially central of the rotor blades, and a second orifice in the stationary structure provides fluidic communication with the first rotor disk face at a location radially peripheral of the rotor blades. An electrical connection to the stator electrode configuration is provided for stator electrode excitation and for power transfer with the stator electrode configuration as the rotor disk rotates.

US Patent:

7074016, Jul 11, 2006

Filed:

May 23, 2003

Appl. No.:

10/445249

Inventors:

Alan H. Epstein - Lexington MA, US
Antoine Deux - Falls Church VA, US
Yoav P. Peles - Rensselaer NY, US
Laurent Jamonet - Aix-en-Provence, FR

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

F01D 1/06
F04B 17/00

US Classification:

417348, 417406, 415 84

Abstract:

A turbopump including a rotor having a first face and a second face and being characterized by a rotor axial height between the first and second rotor faces and by a rotor diameter. A rotor housing includes bearing surfaces for supporting rotation of the rotor, includes turbine inlet and turbine outlet ports and pump inlet and pump outlet ports, and includes pump and turbine fluid sealing surfaces. A plurality of turbine blades of a turbine blade axial height, and a plurality of pump blades of a pump blade axial height, are disposed on a face of the rotor. The turbine blades and pump blades can be together disposed on the rotor first face. Further or alternatively, a turbopump axial height including rotor bearings, turbine blade and pump blade axial height, and rotor axial height, can be less than rotor diameter.

US Patent:

20100122519, May 20, 2010

Filed:

Nov 9, 2009

Appl. No.:

12/614640

Inventors:

Alan Epstein - Lexington MA, US
Richard C. Miake-Lye - Lexington MA, US

International Classification:

F02C 3/20
C10L 1/04
C07C 9/00

US Classification:

60 39461, 208 16, 585 16

Abstract:

A method of managing contrail formation of a gas turbine engine includes delivering an ultra-low sulfur fuel to a combustor of a gas turbine engine to limit an amount of sulfur byproduct produced in an exhaust of the gas turbine engine.

US Patent:

20130220004, Aug 29, 2013

Filed:

Feb 29, 2012

Appl. No.:

13/409036

Inventors:

Alan H. Epstein - Lexington MA, US
Elizabeth A. Mitchell - Marlborough CT, US

International Classification:

G01M 15/14

US Classification:

7311201

Abstract:

An exemplary debris detection method according to one example embodiment of the present disclosure includes, among other things, monitoring turbomachine performance, and initiating a debris warning when an actual rate of change in turbomachine performance varies from a predicted rate of change in the performance.

US Patent:

48120502, Mar 14, 1989

Filed:

Oct 19, 1987

Appl. No.:

7/111846

Inventors:

Alan H. Epstein - Lexington MA
Gerald R. Guenette - Salem MA
Robert J. G. Norton - Kennesaw GA

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G01D 1800
G01K 1500

US Classification:

374 1

Abstract:

Double-sided, high-frequency response heat flux gauge for use on metal tune blading consists of a metal film (1500A) resistance thermometer sputtered on both sides of a thin (25. mu. m) polyimide sheet. The temperature difference across the polyimide is a direct measure of the heat flux at low frequencies, while a quasi-one-dimensional analysis is used to infer the high-frequency heat flux from the upper surface history. A new method of calibrating the heat flux gauge utilizes light source applied to a plurality of fluids covering the surface of the gauge, measuring the temporal output of the gauge and utilizing derived calibration formula.

US Patent:

47226099, Feb 2, 1988

Filed:

May 28, 1985

Appl. No.:

6/738217

Inventors:

Alan H. Epstein - Lexington MA
Gerald R. Guenette - Salem MA
Robert J. G. Norton - Marietta GA

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G01K 1700
H01C 702

US Classification:

374 30

Abstract:

Double-sided, high-frequency response heat flux gauge for use on metal turbine blading consists of a metal film (1500A) resistance thermometer sputtered on both sides of a thin (25. mu. m) polyimide sheet. The temperature difference across the polyimide is a direct measure of the heat flux at low frequencies, while a quasi-ID analysis is used to infer the high-frequency heat flux from the upper surface history.

US Patent:

59044705, May 18, 1999

Filed:

Jan 13, 1997

Appl. No.:

8/791057

Inventors:

Jack L. Kerrebrock - Lincoln MA
Alan H. Epstein - Lexington MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

F04D29/38

US Classification:

415115

Abstract:

Improved performance of counter-rotating turbo machines and compressors. An increase in the thermodynamic efficiency of the compression process is obtained by removing the boundary layer in locations where separation is likely to occur.

US Patent:

51998564, Apr 6, 1993

Filed:

Mar 1, 1989

Appl. No.:

7/317441

Inventors:

Alan H. Epstein - Lexington MA
Edward M. Greitzer - Wayland MA
Daniel L. Gysling - West Newton MA
John Dugundji - Belmont MA
Gerald R. Guenette - Salem MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

F04B 1100

US Classification:

417312

Abstract:

A compressor or pump is connected to a discharge plenum. The plenum includes a movable wall whose motion varies the volume of the plenum. The wall is connected to passive elements forming a spring-mass-damper system whose characteristics are selected to damp pressure fluctuations in the plenum which would give rise to pumping system instabilities. In another aspect of the invention, a compressor is connected to a discharge plenum which in turn is connected to an exit throttle. The throttle includes a movable portion whose motion varies the throttle area. The movable portion is connected to passive elements forming a spring-mass-damper system selected to damp pressure fluctuations in the plenum. In another embodiment, the plenum communicates with a fixed area throttle and a variable area throttle. The variable area throttle includes a movable portion connected to passive elements selected to damp pressure fluctuations in the plenum.