William J Dimarco

US Patent:

55527116, Sep 3, 1996

Filed:

Nov 10, 1994

Appl. No.:

8/336929

Inventors:

Thierry Deegan - Portsmouth RI
William DiMarco - Portsmouth RI

International Classification:

G01N 2762

US Classification:

324464

Abstract:

This invention is a method for determining when combustion cans or turbine blades are failing in gas turbine engines. It measures the specific ions emitted by hot spots of can and blade material when they have failed or are failing. The invention relies on the electromagnetic energy radiated by ions that are created as combustion gas erodes and ionizes the materials in these hot spots. Acceleration by the earth magnetic field and by acoustic and mechanical forces normally present in combustion machinery cause these charged particles to radiate identifiable electromagnetic emissions. The frequency of the radiation, being a function of the charge and mass of the particles, allows free ions in the exhaust stream to be identified. The device operates by measuring the electromagnetic spectrum and relating detected frequencies to the mass of the ions from can liner and blade materials. The device can be used in fixed installations such as power plants, ships and aircraft.

US Patent:

49377582, Jun 26, 1990

Filed:

Sep 4, 1987

Appl. No.:

7/094316

Inventors:

Richard E. Hayden - Sudbury MA
Charles S. Ventres - Cambridge MA
William J. DiMarco - Portsmouth RI
Mervyn D. Floyd - Nashua NH

Assignee:

Technology Integration and Development Group, Inc. - Billerica MA

International Classification:

B64C 2772

US Classification:

364508

Abstract:

Disclosed is a system and method for minimizing vibration over the full operating range of a rotor of an apparatus. The system includes a transducer or an array of transducers for resolving up to six degrees of freedom of motion of a rotor support structure. In one embodiment the transducer is a six degree of freedom accelerometer located near the center of gravity of the structure. In addition to the motion transducer, a shaft position reference sensor is connected to the shaft of the rotor and/or rotor support structure. A signal processor that receives signals from the transducer and the shaft position reference sensor produces Fourier coefficients of motion occurring in each degree of freedom. The system utilizes analytical models or empirically derived data to describe the Fourier coefficients of acceleration (or strain) resulting from each of the available rotor adjustments. The system and method also utilizes an analytical or computational optimization scheme which computes the best combination of rotor adjustments to meet criteria specified by the user.