Domain-Element Method for Aerodynamic Shape Optimization Applied to a Modern Transport Wing

Generic wraparound aerodynamic shape optimization technology is presented and applied to a modern commercial aircraft wing in transonic cruise. The wing geometry is parameterized by a novel domain-element method, which uses efficient global interpolation functions to deform both the surface geometry and corresponding computational fluid dynamics volume mesh. The technique also provides a method that allows geometries to be parameterized at various levels, ranging from global three-dimensional planform alterations to detailed local surface changes. Combining all levels of parameterization allows for free-form design control with very few design variables. The method provides an efficient combined shape parameterization and high-quality mesh deformation technique that is totally independent of mesh type (structured or unstructured). Optimization independence from the flow solver is achieved by obtaining sensitivity information for an advanced gradient-based optimizer by finite differences. The entire optimization suite has also been parallelized to allow optimization with highly flexible parameterization in practical times. Results are presented for highly constrained optimizations of the modern aircraft wing in transonic cruise, using three levels of parameterization (number of design variables) to assess the effect of parameterization level on the optimization. The highest-level optimization results in a totally-shock-free geometry with an associated substantial reduction in drag.

[1]  M. F. Rubinstein,et al.  Automated Structural Synthesis Using a Reduced Number of Design Coordinates , 1973 .

[2]  R. M. Hicks,et al.  Wing Design by Numerical Optimization , 1977 .

[3]  Klaus Schittkowski,et al.  More test examples for nonlinear programming codes , 1981 .

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

[5]  V. Braibant,et al.  Shape optimal design using B-splines , 1984 .

[6]  Ijaz H. Parpia,et al.  van Leer flux vector splitting in moving coordinates , 1988 .

[7]  Antony Jameson,et al.  Aerodynamic design via control theory , 1988, J. Sci. Comput..

[8]  A. Tits,et al.  User's Guide for FSQP Version 2.0 A Fortran Code for Solving Optimization Problems, Possibly Minimax, with General Inequality Constraints and Linear Equality Constraints, Generating Feasible Iterates , 1990 .

[9]  Alan Watt,et al.  Advanced animation and rendering techniques , 1992 .

[10]  A. Tits,et al.  Nonmonotone line search for minimax problems , 1993 .

[11]  André L. Tits,et al.  On combining feasibility, descent and superlinear convergence in inequality constrained optimization , 1993, Math. Program..

[12]  Malcolm I. G. Bloor,et al.  Efficient parametrization of generic aircraft geometry , 1995 .

[13]  E. Robert,et al.  Rapid Airplane Parametric Input Design (RAPID) , 1995 .

[14]  B. Leer,et al.  Flux-vector splitting for the Euler equations , 1997 .

[15]  H. Sobieczky Parametric Airfoils and Wings , 1999 .

[16]  Jamshid A. Samareh,et al.  Status and Future of Geometry Modeling and Grid Generation for Design and Optimization , 1999 .

[17]  J. Samareh Survey of Shape Parameterization Techniques for High-Fidelity Multidisciplinary Shape Optimization , 2001 .

[18]  Christian B Allen,et al.  Multigrid convergence of inviscid fixed‐ and rotary‐wing flows , 2002 .

[19]  Ning Qin,et al.  AERODYNAMIC STUDIES FOR BLENDED WING BODY AIRCRAFT , 2002 .

[20]  Christian B Allen,et al.  Convergence of steady and unsteady formulations for inviscid hovering rotor solutions , 2003 .

[21]  Christian B Allen,et al.  An unsteady multiblock multigrid scheme for lifting forward flight rotor simulation , 2004 .

[22]  Armando Vavalle,et al.  Spanwise Lift Distribution for Blended Wing Body Aircraft. , 2005 .

[23]  Christian B Allen,et al.  Parallel simulation of unsteady hovering rotor wakes , 2006 .

[24]  John E. Bussoletti,et al.  "Fundamental" Parameteric Geometry Representations for Aircraft Component Shapes , 2006 .

[25]  Christian B Allen,et al.  Unified Approach to CFD-CSD Interpolation and Mesh Motion using Radial Basis Functions , 2007 .

[26]  Patrice Castonguay,et al.  Effect of Shape Parameterization on Aerodynamic Shape Optimization , 2007 .

[27]  Patrice Castonguay,et al.  SURVEY OF SHAPE PARAMETERIZATION TECHNIQUES AND ITS EFFECT ON THREE-DIMENSIONAL AERODYNAMIC SHAPE OPTIMIZATION , 2007 .

[28]  Christian B Allen,et al.  Parallel universal approach to mesh motion and application to rotors in forward flight , 2007 .

[29]  B. Kulfan A Universal Parametric Geometry Representation Method - "CST" , 2007 .

[30]  A. Le Moigne,et al.  Parallel adjoint-based optimisation of a blended wing body aircraft with shock control bumps , 2007, The Aeronautical Journal (1968).

[31]  Thomas Rendall,et al.  Development of Generic CFD-Based Aerodynamic Optimisation Tools for Helicopter Rotor Blades , 2007 .

[32]  Christian B Allen,et al.  Efficient Mesh Motion using Radial Basis Functions with Data Reduction Algorithms , 2008 .

[33]  C. Allen,et al.  Unified fluid–structure interpolation and mesh motion using radial basis functions , 2008 .

[34]  Christian B Allen,et al.  CFD‐based optimization of aerofoils using radial basis functions for domain element parameterization and mesh deformation , 2008 .

[35]  John C. Vassberg,et al.  Comparative Study of 3D Wing Drag Minimization by Different Optimization Techniques , 2008 .

[36]  Holger Babinsky,et al.  A combined experimental and numerical study of flow structures over three-dimensional shock control bumps , 2008 .

[37]  Christian B Allen,et al.  Towards automatic structured multiblock mesh generation using improved transfinite interpolation , 2008 .