Development and Implementation of a Novel Parametrization Technique for Multidisciplinary Design Initialization

Development and Implementation of a Novel Parametrization Technique for Multidisciplinary Design Initialization

Straathof, M.H.
Van Tooren, M.J.L.
Voskuijl, M.
Vos, R.

Aerospace Engineering

Aerodynamics, Wind Energy & Propulsion

2010-04-12

A new parametrization method for aircraft shapes is presented to enhance shape optimization for aircraft design. This parametrization method was implemented in a tool that creates feasible initial solutions for multidisciplinary design optimization problems. The tool combines all aspects of the aerodynamic design process: parametrization, aero-dynamic analysis and optimization. The novel parametrization method presented in this paper makes use of the Class-Shape-Refinement-Transformation (CSRT) method. This method employs a combination of Bernstein polynomials and B-splines to allow for both global and local control of the shape. Additionally, the use of B-splines makes it possible to efficiently handle volume constraints, which are very common in aircraft design. The parametrization method was coupled to two different aerodynamic analysis tools. The commercial panel method code VSAERO was used for the low-speed regime and an in-house Euler code was used for transonic and supersonic flight conditions. Various different optimization schemes were investigated and compared. A number of test cases were performed. For the first set of test cases, a three-dimensional geometry was optimized for subsonic conditions, using VSAERO and various optimization algorithms. For the second set of test cases, an airfoil was optimized for transonic and supersonic conditions, using the in-house Euler solver and a gradient-based optimizer. From this work it can be concluded that a combination of stochastic and gradient-based optimization algorithms works best together with the CSRT method. Additionally, refining the shape using B-splines proved to be an efficient way of increasing the design freedom, while the design space remained smooth enough to employ gradient-based optimization.

http://resolver.tudelft.nl/uuid:0f740082-b0b8-436c-8987-006402e2d646

https://doi.org/10.2514/6.2010-3004

American Institute of Aeronautics and Astronautics (AIAA)

978-1-60086-960-0

51st AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, Orlando, USA, 12-15 April 2010; AIAA 2010-3004

Institutional Repository

conference paper

© 2010 American Institute of Aeronautics and Astronautics