Variable-Complexity Response Surface Approximations for Wing Structural Weight in HSCT Design

Kaufman, Matthew and Balabanov, Vladimir and Burgee, Susan L. and Giunta, Anthony A. and Grossman, Bernard and Haftka, Raphael T. and Mason, William H. and Watson, Layne T. (1996) Variable-Complexity Response Surface Approximations for Wing Structural Weight in HSCT Design. Technical Report ncstrl.vatech_cs//TR-96-03, Computer Science, Virginia Polytechnic Institute and State University.

Abstract

A procedure for generating and using a polynomial approximation to wing bending material weight of a High Speed Civil Transport (HSCT) is presented. Response surface methodology is used to fit a quadratic polynomial to data gathered from a series of structural optimizations. Several techniques are employed in order to minimize the number of required structural optimizations and to maintain accuracy. First, another weight function based on statistical data is used to identify a suitable model function for the response surface. In a similar manner, geometric and loading parameters that are likely to appear in the response surface model are also identified. Next, simple analysis techniques are used to find regions of the design space where reasonable HCST designs could occur. The use of intervening variables along with analysis of variance reduce the number of polynomial terms in the response surface model function. Structural optimization is then performed by the program GENESIS on a 28-node Intel Paragon. Finally, optimizations of the HSCT are completed both with and without the response surface.