The Penn State Research Foundation

Other

University of California

Los Alamos National Security, LLC

Robert M Keolian

Kevin J Bastyr

Ray Scott Wakeland

Steven L Garrett

John Feurman Brady

Gregory W Swift

Scott N Backhaus

Robert W Smith

John W Wuthrich

Charles B Cameron

A heat exchanger with a monocoque structure transfers heat between a first fluid and a second fluid. The heat exchanger has a plurality of tubes through which the first fluid may flow in a direction, each of the plurality of tubes has a first mouth end, an opposing second mouth end and a waist region between the first mouth end and the second mouth end. The heat exchanger also has one or more intercom1ected fluid challllels through which the second fluid may flow. the one or more fluid chamlels lay generally in a plane, the plurality of tubes and the one or more fluid channels interleave such that heat may be transferred between the plurality of tubes and the one or more fluid challllels, and the direction of flow of the first fluid is generally perpendicular to the plane of the one or more fluid chamlels.

Monocoque shell and tube heat exchanger

A heat exchanger with a monocoque structure transfers heat between a first fluid and a second fluid. The heat exchanger in has a plurality of tubes through which the first fluid may flow in a direction, each of the plurality of tubes has a first mouth end, an N opposing second mouth end and a waist region between the first mouth end and the second mouth end. The heat exchanger also has one or more interconnected fluid channels through which the second fluid may flow, the one or more fluid channels lay generally in a plane, the plurality of tubes and the one or more fluid channels interleave such that heat may be transferred between the plurality of tubes and the one or more fluid channels, and the direction of flow of the first fluid is generally perpendicular to the plane of the one or more fluid channels.

A high efficiency generator is provided using a Stirling engine to amplify an acoustic wave by heating the gas in the engine in a forward mode. The engine is coupled to an alternator to convert heat input to the engine into electricity. A plurality of the engines and respective alternators can be coupled to operate in a timed sequence to produce multi-phase electricity without the need for conversion. The engine system may be operated in a reverse mode as a refrigerator/heat pump.

In-line stirling energy system

An electroactive transducer converts between acoustical power and electrical power. The transducer includes a diaphragm and a perimeter member. The perimeter member includes at least one electroactive element and is mechanically coupled to the perimeter of the diaphragm such that displacement of the diaphragm stresses the electroactive element.

Thermacoustic piezoelectric generator

A thermoacoustic generator includes a housing with a thermoacoustic core supported in the housing. The core is operable to introduce acoustical power into the housing to thereby oscillate the pressure of the gas in the housing at a frequency. A piezoelectric alternator is also supported in the housing and has a face that is movable when acted on by the acoustical power. The alternator includes a portion of piezoelectric material operable to produce electrical power when acted upon by a stress. The piezoelectric material is in mechanical communication with the movable face so that movement of the face stresses the piezoelectric material. The alternator has a moving mass that serves as a substantial portion of the resonating mass inside the housing, thereby providing a pressure oscillation frequency in the housing substantially lower than for a similar system with a rigid member replacing the alternator.

Thermoacoustic piezoelectric generator

A thermoacoustic driver incorporates a linear electrodynamic motor having electrical terminals and a moving part, a driver suspension housing, a piston, and a stiffness-enhancing device for raising the mechanical resonance frequency of the electrodynamic motor without reducing the piston stroke. The stiffness enhancement is accomplished by the use of specially optimized suspension spring structures and/or by attaching one or more electrical inductors to the electrical terminals of the driver. The stiffness enhancement using mechanical springs incorporates one or more starfish structures extending between the driver suspension housing and the piston and rigidly clamped to both. The starfish structures comprise radially extending legs, which are leaf springs or beams of varying width. The shape of the beams and the shape of the overall spring structure are optimized to enhance flexural or torsional stiffness and relieve arc tension within the constraints of cost-effectiveness. In one version, two modified triangular (trapezoidal) cantilever beams are connected through a straight middle section and form a bow-tie shaped beam.

High-efficiency moving-magnet loudspeaker

A thermoacoustic stack for connecting two heat exchangers in a thermoacoustic energy converter provides a convex fluid-solid interface in a plane perpendicular to an axis for acoustic oscillation of fluid between the two heat exchangers. The convex surfaces increase the ratio of the fluid volume in the effective thermoacoustic volume that is displaced from the convex surface to the fluid volume that is adjacent the surface within which viscous energy losses occur. Increasing the volume ratio results in an increase in the ratio of transferred thermal energy to viscous energy losses, with a concomitant increase in operating efficiency of the thermoacoustic converter. The convex surfaces may be easily provided by a pin array having elements arranged parallel to the direction of acoustic oscillations and with effective radial dimensions much smaller than the thicknesses of the viscous energy loss and thermoacoustic energy transfer volumes.

Pin stack array for thermoacoustic energy conversion

A highly sensitive optical fiber interferometer sensor comprising a laser light source, a [2.times.2] optical fiber coupler to split the beam in two, a differential transducer which converts a signal of interest into optical phase shift in the laser light transmitted through the two optical fibers in the interferometer and a [3.times.3] optical fiber complex which recombines the two beams, producing interference which can be electronically detected. The use of the [3.times.3] coupler permits Passive Homodyne demodulation of the phase-modulated signals provided by the interferometer without feedback control or modulation of the laser itself and without requiring the use of electronics within the interferometer.

Growing community of inventors

Monterey, CA, United States of America

Robert M Keolian