Design optimization for subsonic and supersonic aircraft and for air-breathing propulsion engine concepts has been accomplished by soft-coupling the Flight Optimization System (FLOPS) and the NASA Engine Performance Program analyzer (NEPP), to the NASA Lewis multidisciplinary optimization tool COMETBOARDS. Aircraft and engine design problems, with their associated constraints and design variables, were cast as nonlinear optimization problems with aircraft weight and engine thrust as the respective merit functions. Some of COMETBOARDS' unique features, which include a cascade strategy, variable and constraint formulations, and scaling devised especially for difficult multidisciplinary applications, successfully optimized the performance of both aircraft and engines. The cascade method has two principal steps: In the first, the solution initiates from a user-specified design and optimizer, in the second, the optimum design obtained in the first step with some random perturbation is used to begin the next specified optimizer. The second step is repeated for a specified sequence of optimizers or until a successful solution of the problem is achieved. This paper describes COMETBOARDS and its cascade strategy and illustrates the capability of the combined design tool through the optimization of a subsonic aircraft and a high-bypass-turbofan wave-rotor-topped engine.
Cascade Optimization Strategy for Aircraft and Air-Breathing Propulsion System Concepts
1996
14 pages
Report
No indication
English
Jet & Gas Turbine Engines , Aircraft , Computer Aided Design, CAD , Air breathing engines , Aircraft design , Aircraft engines , Computer aided design , Engine design , Multidisciplinary design optimization , Thrust-weight ratio , Turbofan engines , Convergence , Linear programming , Structural weight
Cascade Optimization Strategy for Aircraft and Air-Breathing Propulsion System Concepts
Online Contents | 1997
|Cascade Optimization Strategy for Aircraft and Air-Breathing Propulsion System Concepts
British Library Conference Proceedings | 1996
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