Harry Kirk Mathews

Advanced Estimation for Aircraft Engines

This paper reviews recent industrial applications of estimation techniques to aircraft engines. Estimation is considered here in a broad sense. An estimator is any algorithm that processes engine measurements to compute engine signals, or parameters of interest, that are not directly measured. The paper begins with a summary of aircraft engines fundamentals, followed by brief descriptions of basic concepts in the areas of engine controls, engine fault detection and isolation, and engine health management. Practical estimation-based approaches in these areas are covered in some detail. These approaches include: control schemes that regulate estimated thrust, fault detection and classification algorithms based on estimator residuals, and health monitoring procedures that track deterioration of key engine model parameters. Several case studies, based on recent programs at GE Global Research and GE Aviation, are described in detail. These case studies contain validations of the proposed solutions via implementations using high-fidelity engine models. The paper concludes with a review of some open problems. This paper intends to be a starting point for researchers in academia and industry looking for an overview of estimation methods used in industrial jet engine applications.

Apparatus and method for boil phase detection based on acoustic signal features

An apparatus and method for determining at least one boil phase of a liquid is provided. The boil phase is determined from an acoustic signal generated by the liquid during heating, the acoustic signal is measured by an acoustic sensor. The apparatus comprises at least one filter connected to the acoustic sensor. The at least one filter receives and filters the acoustic signal to eliminate excess variation and to eliminate high frequency noise from the acoustic signal producing a filtered acoustic signal. At least one derivative estimation filter is also provided and is connected to the at least one filter. The at least one derivative estimation filter estimates at least one derivative of the filtered acoustic signal. A processor is provided and is connected to the at least one filter and the at least one derivative estimation filter. The processor identifies the at least one boil phase of the liquid using at least the filtered acoustic signal and at least one derivative of the filtered acoustic signal.