ATR Performance Estimation Seed Program

A linear point design methodology for minimizing the error in on-line Kalman filter-based aircraft engine performance estimation applications is presented. This technique specifically addresses the underdetermined estimation problem, where there are more unknown parameters than available sensor measurements. A systematic approach is applied to produce a model tuning parameter vector of appropriate dimension to enable estimation by a Kalman filter, while minimizing the estimation error in the parameters of interest. Tuning parameter selection is performed using a multivariable iterative search routine that seeks to minimize the theoretical mean-squared estimation error. This paper derives theoretical Kalman filter estimation error bias and variance values at steady-state operating conditions, and presents the tuner selection routine applied to minimize these values. Results from the application of the technique to an aircraft engine simulation are presented and compared with the conventional approach of tuner selection. Experimental simulation results are found to be in agreement with theoretical predictions. The new methodology is shown to yield a significant improvement in on-line engine performance estimation accuracy.

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A Model for Performance Estimation of Flapping Foil Operating as Biomimetic Stream Energy Device

Journal of Marine Science and Engineering ◽

10.3390/jmse9010021 ◽

2020 ◽

Vol 9 (1) ◽

pp. 21

Author(s):

Iro E. Malefaki ◽

Kostas A. Belibassakis

Keyword(s):

Vertical Axis ◽

Flow Speed ◽

Performance Estimation ◽

Speed Ratio ◽

Power Extraction ◽

Flapping Foil ◽

Flow Energy ◽

Novel Concept ◽

Angular Oscillations ◽

Energy Converters

During the recent period intensive research has focused on the advancement of engineering and technology aspects concerning the development and optimization of wave and current energy converters driven by the need to increase the percentage of marine renewable sources in the energy-production mix, particularly from offshore installations. Most stream energy-harvesting devices are based on hydro-turbines, and their performance is dependent on the ratio of the blade-tip speed to incident-flow speed. As the oncoming speed of natural-occurring currents varies randomly, there is a penalty for the latter device’s performance when operating at non-constant tip-speed ratio away from the design value. Unlike conventional turbines that are characterized by a single degree of freedom rotating around an axis, a novel concept is examined concerning hydrokinetic energy converters based on oscillating hydrofoils. The biomimetic device includes a rotating, vertically mounted, biomimetic wing, supported by an arm linked at a pivot point on the mid-chord. Activated by a controllable self-pitching motion the system performs angular oscillations around the vertical axis in incoming flow. In this work, the performance of the above flapping-foil, biomimetic flow energy harvester is investigated by application of a semi-3D model based on unsteady hydrofoil theory and the results are verified by comparison to experimental data and a 3D boundary element method based on vortex rings. By systematical application of the model the power extraction and efficiency of the system is presented for various cases including different geometric, mechanical, and kinematic parameters, and the optimal performance of the system is determined.

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Dynamic performance estimation: A design tool for mechatronic scanners

IFAC-PapersOnLine ◽

10.1016/j.ifacol.2020.12.1579 ◽

2020 ◽

Vol 53 (2) ◽

pp. 8407-8412

Author(s):

E. Csencsics ◽

G. Schitter

Keyword(s):

Dynamic Performance ◽

Design Tool ◽

Performance Estimation

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