Flexing Wind

The aims of the Flexing Wind project, investigated in an intensive cross-disciplinary course, were twofold. First was to learn about aerodynamic phenomena around buildings. Second was to explore ways to observe, measure, and control the negative effects of wind around specific pedestrian areas, tram stops, and public sites in Melbourne City....

Vortex-lift modeling provides reliable force predictions for flapping-wing Micro Air Vehicles

Vertical and horizontal force of a flapping-wing micro air vehicle (MAV) has been measured in slow-speed forward flight using a force balance. Detailed information on kinematics was used to estimate forces using a blade-element analysis. Input variables for this analysis are lift and drag coefficients. These coefficients are usually derived from...

Transient Analysis of Nylon 6/6 for a Thin Shell Structure by FEM

In the design of Micro Aerial Vehicles, decreasing the size is one of the most common challenging aims and to approach this aim, the weight of the whole aircraft shall decrease and structure is the second part which has the most weight [13]. In this paper, the use of a shell structure made from Nylon 6/6 is studied. Nylon was chosen because of...

Aerodynamic analysis of the wing ?exibility and the clap-and-peel motion of the hovering DelFly II

In this paper, the influence of wing flexibility and the 'clap-and-peel' motion (one versus two wings) on the upward (lifting) force in hover is studied. CFD simulations based on the ALE Navier-Stokes equations together with radial basis function mesh interpolation are used. For the 'clap-and-peel' motion an immersed symmetry plane is introduced...

Numerical investigation of disc-wing MAV with propeller in a wing slot

Concept of dis?-wing MAV with propeller in a wing slot has a number of advantages and disadvantages. The concept is used by MIPTEAM for solving the problem of fixed wing MAV indoor flight by means of lift maximization for wing with low aspect ratio. There are only few investigations of dis?-wing MAV aerodynamics with propeller in a wing slot....

Aerodynamics Study of Fixed-Wing MAV: Wind Tunnel and Flight Test

Obtaining accurate aerodynamic characteristics of in-flight Micro Air Vehicles (MAVs) was viewed as difficult, due to the nature of very low Reynolds number, 3D complex flow, and strong influence from propulsion slipstream. This paper presents the study of the tailless, fixed-wing MAV, KuMAV-001, performed at Kasetsart University. The team...

Adjoint approaches in aerodynamic shape optimization and MDO context

Because detailed aerodynamic shape optimizations still suffer from high computational costs, efficient optimization strategies are required. Regarding the deterministic optimization methods, the adjoint approach is seen as a promising alternative to the classical finite difference approach. With the adjoint approach the sensitivities needed for...

Hierarchical Methods for Shape Optimization in Aerodynamics: Multilevel parametric shape algorithms and additive preconditioners

This lecture is devoted to the presentation of two particular "hierarchical" approaches to numerical shape optimization in aerodynamics design: 1) multilevel parametric shape optimization algorithms; 2) additive preconditioners. The first approach is inspired from the classical geometrical multigrid method, except that here the geometrical...

Large scale urban simulations with MILES

Airborne contaminant transport in cities presents challenging new requirements for CFD. The unsteady flow physics is complicated by very complex geometry, multi-phase particle and droplet effects, radiation, latent, and sensible heating effects, and buoyancy effects. Turbulence is one of the most important of these phenomena and yet the overall...

Optimization of Blended Wing Body Aircraft by Automatic CFD Driven Design Tool

Blended Wing Body (BWB) Aircraft has aroused a considerable interest as a potential candidate for future large subsonic transport air-vehicles. In this paper, we present the results of one and multi-point multi-constrained optimization of a BWB configuration for minimum total drag. The optimization technique is based on Genetic Algorithms and is...

Image-based method for the aerodynamic characteristics of a motor cycle

In this paper, a simple analysis method for flow simulations around a motor cycle is discussed based on CFD. In the practical CFD, most of the efforts are wasted for grid generations. The typical two types of grid are body-fitted grid and Cartesian grid. Body-fitted grid was often used for the flow calculation around the vehicle until today....

Aerodynamical Global Optimal Shape Design, with Stiffness Constraints

The optimization strategy is an own, two times enlarged variational method, which is able to perform the global, optimal design (OD) and to include the friction effect in the computation of the total drag functional and in the OD. The first enlargement consists in the inviscid global OD of the flying configuration’s (FC’s) shape (namely, the...

Aerodynamic Shape Optimization by means of Sequential Linear Programming Techniques

An optimization framework for aerodynamic design on unstructured meshes has been implemented. It includes a finite volume solver based upon a median-dual discretization, its discrete adjoint, and shape parameterization and mesh moving/deforming algorithms. The framework elements are coupled and linked to a Sequential Quadratic Programming (SQP)...

Error estimation and adjoint-based adaptation in aerodynamics

We give an overview of recent developments in error estimation and in residual-based and goal-oriented (adjoint-based) adaptation for Discontinuous Galerkin discretizations of sub- and supersonic viscous compressible flows. We also give an outlook on the planned continuation of this research in the EU project ADIGMA.

Fluid-structure iterative algorithms using pressure segregation methods and their application to bridge aerodynamics

In this paper we suggest some algorithms for the fluid-structure interaction problem stated using a domain decomposition framework. These methods involve stabilized pressure segregation methods for the solution of the fluid problem and fixed point iterative algorithms for the fluid-structure coupling. These coupling algorithms are applied to the...