Abstract A nearly two-dimensional vortex of small core size has been produced by the transient plunging motion an upstream airfoil and it interacted with downstream wings. Depending on offset distance wing angle attack, incident filament deforms, diffuses, loses coherence, while inducing leading-edge formation shedding from wing. No significant spanwise flow develops in vortices during interact...

The purpose of this study is to improve the aerodynamic performance of wind turbine blades, using the Ball-Spine inverse design method. The inverse design goal is to calculate a geometry corresponds to a given pressure distribution on its boundaries. By calculating the difference between the current and target pressure distributions, geometric boundaries are modified so that the pressure di...

Optimizing the NACA0015 airfoil which is widely applied in small-scale vertical axis wind turbine to make it has a better aerodynamic performance. In the optimization process, using CST parameterization method to perturb the airfoil geometry, the thickness and camber of the airfoil are selected as the constraint, and the value of the maximum tangential force coefficient is chosen as the objecti...

The goal of this research is to develop a versatile and fast code to compute the unsteady lift and thrust forces generated by a flapping airfoil and apply it to engineering problems. We consider both plunging and pitching types of motion and develop a time marching simulation based on early work in unsteady aerodynamics. The ability of the code to compute lift and thrust forces is validated aga...

This paper presents a multi‐dimensional high‐order discontinuous Galerkin (DG) method in an arbitrary Lagrangian‐Eulerian (ALE) formulation to simulate flows over variable domains with moving and deforming meshes. It is an extension of the gas‐kinetic DG method proposed by the authors for static domains (X. Ren et al., A multi‐dimensional high‐order discontinuous Galerkin method based on gas ki...

A potential flow model is used to study the unsteady flow past two airfoils in configuration, each of which is suddenly set into motion. The airfoil bound vortices are modeled using lumped vortex elements and the wake behind the airfoil is modeled by discrete vortices. This consists of solving a steady state flow problem at each time-step where unsteadiness is incorporated through the “zero nor...

Numerical simulations are presented in order to test airfoil optimization criteria from the aeroelastic point of view. Based on an Evolution Strategy, airfoil-shape point optimization has been performed as a lift constrained drag minimization at a given Mach/Reynolds number combination for transonic flow. Additional to the drag minimization, the propagation time of pressure disturbances from th...

This experimental works summarize the (1), aeroacoustic results of airfoil self-noise generated at Reynolds numbers between 1.0 x 10 and 6.0 x 10. The test facility is a newly built low noise and low flow turbulence open jet wind tunnel, where a NACA0012 airfoil was mounted to the exit nozzle horizontally. The noise measurements were performed at three effective angles of attack at 0.0, 1.4 and...

Two dual-point design procedures were developed to reduce the objective function of a baseline airfoil at two design points. The rst procedure to develop a redesigned airfoil used a weighted average of the shapes of two intermediate airfoils redesigned at each of the two design points. The second procedure used a weighted average of two pressure distributions obtained from an intermediate airfo...