Aerostructural Design Exploration of a Wing in Transonic Flow

Abstract

Multidisciplinary design optimization (MDO) has been previously applied to aerostructural wing design problems with great success. Most previous applications involve fine-tuning a well-designed aircraft wing. In this work, we broaden the scope of the optimization problem by exploring the design space of aerostructural wing design optimization. We start with a rectangular wing and optimize the aerodynamic shape and the sizing of the internal structure to achieve minimum fuel burn on a transonic cruise mission. We use a multi-level optimization procedure to decrease computational cost by 40%. We demonstrate that the optimization can transform the rectangular wing into a swept, tapered wing typical of a transonic aircraft. The optimizer converges to the same wing shape when starting from a different initial design. Additionally, we use a separation constraint at a low-speed, high-lift condition to improve the off-design performance of the optimized wing. The separation constraint results in a substantially different wing design with better low-speed performance and only a slight decrease in cruise performance.

Numerical Modelling of Static Aeroelastic Deformations of Slender Wing in Aerodynamic Design

“…where: G = {G 1 , … ,G N } T are known values of interpolation function in source points, and P is a constraint matrix of the form: (6) In the described implementation of RBF functions, the interpolated variables (scalars S in Eq. ( 1)) are components of transitions of the nodes of the computational mesh: (7) The node translations described above depend on translations defined in source points, which need not be mesh nodes.…”

“…On the other hand, there is an expressed trend of using higher fidelity methods as early as possible in the project cycle, which can be especially important when designing unconventional structures [5] or considering transonic flow [6]. When optimization of the design concerning performance becomes necessary, sufficient information about aerodynamic characteristics and aircraft loads may be obtained from solutions of RANS equations, which are becoming more and more efficient and friendly in use due to the parallelization of solutions, development of reliable turbulence models (GEKO, Transition-SST), adjoint solvers, and effective meshing techniques, such as polyhedra and overset, which improve the accuracy of gradients of flow variables and speed-up convergence of the solution.…”

Discrete and Continuous Adjoint-Based Aerostructural Wing Shape Optimization of a Business Jet

“…During the last two decades, high-fidelity CFD and computational structural mechanics (CSM) tools have almost exclusively been used. For instance, in [10,11] Euler CFD codes were employed, while the use of CFD models involving the solution of the Reynolds-Averaged Navier-Stokes (RANS) equations into aerostructural shape optimization problems can be found in [12][13][14][15][16][17][18]. More accurate fluid flow models, such as large-eddy and direct numerical simulations, can be used too.…”

“…The results reconfirmed the importance of including aerostructural coupling in shape optimization. In [17], single-and multi-point aerostructural wing optimizations including a flow separation constraint at low-speed, highlift conditions were performed. The flow separation constraint resulted in a substantially different wing design with better low-speed performance and only a slight decrease in cruise performance.…”

Concurrent Trajectory Optimization and Aircraft Design for the Air Cargo Challenge Competition

“…On one hand, the aircraft design should take into account both aerodynamics and structures, aiming to maximize lift for take-off and speed for cruise while actively reducing the overall weight and drag. The aerodynamic and structural disciplines need to be coupled in the form of aerostructural design, as proved necessary in most aircraft design problems from simple configurations to vastly complex, such as multi-operating point conditions [7], morphing wings [8], transonic wings [9] and box-wing configurations [10]. The design process focuses on the conceptual phase, to provide an overview of the aircraft shape, size, weight and performance, given the specified operating conditions [11].…”