Robust structural design of a simplified jet engine model, using Multiobjective optimization

Engine component and transducer degradation/fault diagnosis, are analyzed. The analysis is performed using an aero-thermodynamic nonlinear inverse jet-engine model while using data acquired during transient engine operation. A shortened inverse jet-engine model (without one or more engine component maps) was recently proposed by the authors for real-time simulations and for fast evaluation of engine component maps. The algorithm for the engine component’s fault diagnosis is significantly simplified using shortened inverse engine models. A diagnostic example of combined faults of a single transducer and a single engine component for a single spool jet engine is described using different combinations of shortened inverse jet engine models. In the present paper it is assumed that only a single transducer (out of the seven transducers) and /or a single engine component (compressor or turbine) fault could be present in the engine at a given time.

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Multiobjective Optimization for Structural Design of Lunar Habitats

Earth and Space 2018 ◽

10.1061/9780784481899.018 ◽

2018 ◽

Author(s):

Valentina Sumini ◽

Sam Wald ◽

Caitlin Mueller ◽

Claudio Chesi ◽

Olivier L. de Weck

Keyword(s):

Multiobjective Optimization ◽

Structural Design

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Multiobjective Optimization for the Aero-Structural Design of Adaptive Compliant Wing Devices

Applied Sciences ◽

10.3390/app10186380 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6380

Author(s):

Alessandro De Gaspari

Keyword(s):

Multiobjective Optimization ◽

Structural Design ◽

Design Method ◽

Three Dimensional ◽

Compliant Structure ◽

Aircraft Performance ◽

Definition Of ◽

Shape Changes ◽

Multiple Load ◽

Load Conditions

The design of morphing structures must combine conflicting structural requirements and multiple load conditions that are related to the aerodynamic shapes aimed at optimizing aircraft performance. This article proposes a multilevel approach for the design of adaptive compliant wing devices. A set of aerodynamic shapes, and associated their loads, is defined by a shape optimization, coupled with a three-dimensional parametric technique, that can identify only feasible shape changes due to the morphing. A topology and sizing multiobjective optimization drives the Pareto-optimal structural design of the compliant structure, which is able to deform itself to match, once actuated, all of the previously defined aerodynamic shapes. Next two design levels produce a more detailed solution which is extended until the definition of the complete device. A 90 pax, twin prop green regional aircraft is used as an innovative aircraft demonstration platform for the design of the morphing droop nose to be installed on the wing. The results show the structural capabilities of this device in terms of the external shape quality and the strain requirements. This work enables the validation of the design method and prove the functionality of compliant structures when accounting for the aeroelastic effects due to the interaction with the wing-box.

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Model Based Control Concepts for Jet Engines

Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; IGTI Scholar Award ◽

10.1115/2001-gt-0016 ◽

2001 ◽

Cited By ~ 12

Author(s):

Klaus Lietzau ◽

Andreas Kreiner

Keyword(s):

Turbine Blades ◽

Engine Performance ◽

Current Control ◽

Engine Control ◽

Jet Engines ◽

Jet Engine ◽

Engine Model ◽

Model Based ◽

Safety Margins ◽

Engine Life

Many jet engine variables cannot be measured in-flight or can only be measured with a complex, and hence unreliable, instrumentation system. This includes variables that are of imminent importance for the safe operation of the engine or for engine life, such as the temperature of the high pressure turbine blades or the surge margins of the turbo compressors, for instance. Current control systems therefore transform limits on these variables into limits on other variables measured by the engine’s sensors. This leads to increased safety margins and thus to non-optimal engine performance. An onboard engine model incorporated into the engine control system could provide information about all engine variables. This could enable further control and monitoring system optimisations leading to improved engine performance, reduced fuel consumption, increased safety and engine life. This paper explains the principle of model based engine control and gives an overview about possible applications for conventional and also thrust vectored jet engines. Modeling methods for real-time simulation as well as methods for online model adaptation are presented. The potential of model based jet engine control is analyzed and fortified by some prototype realizations.

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Enhancing the Performance of Jet Engine Fuel Controller Using Neural Networks

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.390.393 ◽

2013 ◽

Vol 390 ◽

pp. 393-397

Author(s):

Mehrdad Bazazzadeh ◽

Ali Shahriari

Keyword(s):

Neural Network ◽

Fuzzy Logic ◽

Fuzzy Logic Controller ◽

Inlet Temperature ◽

Turbine Inlet Temperature ◽

Jet Engine ◽

Engine Model ◽

Fuel Flow ◽

Compressor Surge ◽

Flow Functions

This paper proposes a fuzzy logic controller for a specific turbojet engine. The turbine engines require control systems to achieve the appropriate performance. The control systems typically featured loops to prevent engine flame out, over speeds, compressor surge, and check turbine inlet temperature limit, either by scheduling the fuel flow during accelerations and decelerations or by controlling the acceleration and deceleration rates of engine spool. This paper presents a successful approach in designing a Fuzzy Logic Controller for a specific Jet Engine. At first a suitable mathematical model for the jet engine is presented by the aid of SIMULINK simulation software. Then by applying different reasonable fuel flow functions via the engine model, some important engine continuous time operation parameters (such as: thrust, compressor surge margin, turbine inlet temperature and engine spool speed...) are obtained. These parameters provide a precious database which can be used by a neural network. At the second step, by designing and training a feedforward multilayer perceptron neural network according to this available database; a number of different reasonable fuel flow functions for various engine acceleration operations are determined. These functions are used to define the desired fuzzy fuel functions. Indeed, the neural networks are used as an effective method to define the optimum fuzzy fuel functions. At the next step we design a fuzzy logic controller by using the engine simulation model and the neural network results. The proposed control scheme is proved by computer simulation using the designed engine model. The simulation results of engine model with fuzzy controller in comparison with the engine testing operation illustrate that the proposed controller achieves the desired performance.

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Trade-off analysis for structural design of high-precision space reflector using multiobjective optimization method

Mechanical Engineering Journal ◽

10.1299/mej.15-00058 ◽

2015 ◽

Vol 2 (4) ◽

pp. 15-00058-15-00058

Author(s):

Ryo KODAMA ◽

Nozomu KOGISO ◽

Masahiro TOYODA ◽

Hiroaki TANAKA

Keyword(s):

Multiobjective Optimization ◽

High Precision ◽

Structural Design ◽

Optimization Method ◽

Trade Off

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Deterioration Detection and Health Monitoring in Aircraft Jet Engines

Volume 1: Advances in Aerospace Technology ◽

10.1115/imece2012-87938 ◽

2012 ◽

Author(s):

N. Daroogheh ◽

A. Baniamerian ◽

H. Nayyeri ◽

K. Khorasani

Keyword(s):

Performance Analysis ◽

Statistical Method ◽

Health Monitoring ◽

Engine Performance ◽

Jet Engines ◽

Differential Analysis ◽

Analysis Method ◽

Jet Engine ◽

Engine Model ◽

Cumulative Sum Method

In this paper the problem of jet engine deterioration detection and health monitoring is investigated by utilizing two methods. The first method is based on the fusion of the modified CUSUM (CUmulative SUM) method with the differential analysis approach. An enhanced differential analysis method is developed through which the degradation is captured from the unsymmetrical performance analysis of both engines on an aircraft. This is achieved by considering the effects of minor maintenance actions that are not reported. In the second approach, a statistical method based on the Hotelling’s T2-test approach is utilized to detect gradual degradations in the engine performance. The performance of our proposed approaches is evaluated by implementing them on a dual spool engine model that is developed by using the GSP software.

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