General-purpose optimization method for multidisciplinary design applications

A general-purpose optimization tool for multidisciplinary applications, whi ch in the literature is known as COMETBOARDS, is bring developed at NASA Le wis Research Center. The modular organization of COMETBOARDS includes sever al analyzers and state-of-the-art optimization algorithms along with their cascading strategy. The code structure allows quick integration of new anal yzers and optimizers. The COMETBOARDS code reads input information from a n umber of data files, formulates a design as a set of multidisciplinary nonl inear programming problems, and then solves the resulting problems. COMETBO ARDS can be used to solve a large problem, which can be defined through mul tiple disciplines, each of which can be further broken down into several su bproblems. Alternatively, a small portion of a large problem can be optimiz ed in an effort to improve an existing system. Some of the other unique fea tures of COMETBOARDS include design variable formulation, constraint formul ation, subproblem coupling strategy, global scaling technique, analysis app roximation, use of either sequential or parallel computational modes, and s o forth. The special features and unique strengths of COMETBOARDS assist co nvergence and reduce the amount of CPU time used to solve the difficult opt imization problems of aerospace industries. COMETBOARDS has been successful ly used to solve a number of problems, including structural design of space station components, design of nozzle components of an air-breathing engine , configuration design of subsonic and supersonic aircraft, mixed flow turb ofan engines, wave rotor topped engines, and so forth. This paper introduce s the COMETBOARDS design tool and its versatility, which is illustrated by citing examples from structures, aircraft design, and air-breathing propuls ion engine design. (C) 2000 Elsevier Science Ltd. All rights reserved.