Getting the Full Benefits of CFD in Conceptual Design

The applied aerodynamics community is struggling to develop a means of incorporating computational fluid dynamics (CFD) into the early stages of aircraft systems design, where it can have the greatest impact on vehicle design. This paper describes developments in computational design methodology arising from research into multidisciplinary design optimization (MDO) done recently by the authors that addresses this problem. The premise is that advanced CFD should be used to precompute a database of solutions which is then interpolated during the design process. Design of experiments theory is used to select the "conditions" or "design points" used to populate the database, and statistical methods are then used to develop a mathematical model of the CFD solutions which is used to "interpolate" the database. The specific models we use, called "response surface models" are quadratic least squares fits to functions of the CFD results. Populating the database is made possible through the use of coarse grained parallel computing. We demonstrate the method using a recent example from our MDO work.

[1]  Garret N. Vanderplaats,et al.  Numerical Optimization Techniques for Engineering Design: With Applications , 1984 .

[2]  Andrew J. Booker,et al.  A comparison of optimization and search methods for multidisciplinary design , 1992 .

[3]  J. S. Kowalik,et al.  Airplane Engine Selection by Optimization on Surface Fit Approximations , 1975 .

[4]  Douglas C. Montgomery,et al.  Response Surface Methodology: Process and Product Optimization Using Designed Experiments , 1995 .

[5]  Bernard Grossman,et al.  Multidisciplinary design optimization of advanced aircraft configurations , 1997 .

[6]  Dimitri N. Mavris,et al.  An Application of Response Surface Methodology to the Design of Tipjet Driven Stopped Rotor/Wing Concepts , 1995 .

[7]  Kathryn M. Chalfan,et al.  A Knowledge System that Integrates Heterogeneous Software for a Design Application , 1986, AI Mag..

[8]  P. Gelhausen,et al.  ACSYNT - A standards-based system for parametric, computer aided conceptual design of aircraft , 1992 .

[9]  Jaroslaw Sobieszczanski-Sobieski,et al.  Multidisciplinary aerospace design optimization - Survey of recent developments , 1996 .

[10]  Robert M Kulfan,et al.  Wing planform geometry effects on large subsonic military transport airplanes. Final technical report March 1976-February 1977 , 1978 .

[11]  Karl A. Geiselhart,et al.  A technique for integrating engine cycle and aircraft configuration optimization , 1994 .

[12]  Antony Jameson,et al.  Essential Elements of Computational Algorithms for Aerodynamic Analysis and Design , 1997 .

[13]  I. H. Rettie,et al.  Role of Figures of Merit in Design Optimization and Technology Assessment , 1981 .

[14]  Bernard Grossman,et al.  Variable-complexity response surface aerodynamic design of an HSCT wing , 1995 .

[15]  Layne T. Watson,et al.  Dependence of optimal structural weight on aerodynamic shape for a High Speed Civil Transport , 1996 .

[16]  Raphael T. Haftka,et al.  Variable-complexity aerodynamic optimization of a high-speed civil transport wing , 1994 .

[17]  Margaret J. Robertson,et al.  Design and Analysis of Experiments , 2006, Handbook of statistics.

[18]  T Watson Layne,et al.  Multidisciplinary Optimization of a Supersonic Transport Using Design of Experiments Theory and Response Surface Modeling , 1997 .

[19]  S. A. Powers,et al.  Drag minimization using exact methods , 1964 .

[20]  R. J. Mack,et al.  Estimation of Attainable Leading-Edge Thrust for Wings at Subsonic and Supersonic Speeds , 1979 .

[21]  Antony Jameson,et al.  Re-engineering the design process through computation , 1997 .

[22]  John E. Renaud,et al.  Response surface based, concurrent subspace optimization for multidisciplinary system design , 1996 .

[23]  David Nixon,et al.  Conceptual Design Method for Wings at Transonic Speeds , 1997 .

[24]  Robert M. Kulfan,et al.  Wing Planforms for Large Military Transports , 1978 .

[25]  Roy T. Schemensky,et al.  Development of an Empirically Based Computer Program to Predict the Aerodynamic Characteristics of Aircraft. Volume I. Empirical Methods , 1973 .

[26]  Bernard Grossman,et al.  Response surface approximations for pitching moment including pitch-up in the MDO design of an HSCT , 1996 .

[27]  Garret N. Vanderplaats,et al.  Numerical optimization techniques for engineering design , 1999 .

[28]  Douglas O. Stanley,et al.  Aerodynamic configuration design using response surface methodology analysis , 1993 .

[29]  James Snyder.  CFD needs in conceptual design , 1990 .

[30]  R. C. Feagin,et al.  Delta method, an empirical drag buildup technique , 1978 .

[31]  Raphael T. Haftka,et al.  An MDO investigation of the impact of practical constraints on an HSCT configuration , 1997 .

[32]  Harry W. Carlson,et al.  Numerical methods and a computer program for subsonic and supersonic aerodynamic design and analysis of wings with attainable thrust considerations , 1984 .