High aspect-ratio grids are required for accurate solution of boundary layer and wake flow. An approach for the efficient generation f isotropic and stretched viscous unstructured grids is introduced in this paper. The proposed grid generation algorithm starts with very coarse initial grid. In far field regions, isotropic cells of excellent quality are produced using a combination of point inse...

We present a comparison between hybridized and non-hybridized discontinuous Galerkin methods in the context of target-based hp-adaptation for compressible flow problems. The aim is to provide a critical assessment of the computational efficiency of hybridized DG methods. Hybridization of finite element discretizations has the main advantage, that the resulting set of algebraic equations has glo...

The recent development of large wind turbines poses new challenges with regard to understanding the mechanisms surrounding unsteady flow-structure interaction. The larger and more flexible blades imply risks from an aeroelastic point of view and urge the need to properly understand and model these phenomena. Due to limited experimental data available in this field, Computational Fluid dynamics ...

Abstract It is known that plunging airfoil can produce both lift and thrust with certain combination of plunging amplitude and frequency. Motivated by our interest in micro air vehicles (MAVs), we utilize a NavierStokes equation solver to investigate the aerodynamics of a flapping airfoil. The roles of the plunging and pitching amplitude and frequency, and Strouhal number are studied. For a sym...

Due to their small size and flight regime, coupling of aerodynamics, structural dynamics, and flight dynamics is critical for Micro Aerial Vehicles. This paper presents a computational framework for simulating structural models of varied fidelity and a Navier-Stokes solver, aimed at simulating flapping and flexible wings. The structural model utilizes either (i) the in-house developed UM/NLABS,...

The design of wind turbines requires a deep insight into their complex aerodynamics, such as dynamic stall single airfoil and flow vortices. calculation the aerodynamic forces on turbine blade at different angles attack (AOAs) is fundamental task in blades. accurate efficient (lift drag) prediction an are challenging tasks. Computational fluid dynamics (CFD) able to provide better understanding...

Abstract The post-stall flow control using compliant flags of varying thickness and length, placed upstream a NACA0012 airfoil, was shown to be possible at an airfoil chord Reynolds number 100,000. flag wakes produced substantial increase in the stall angle maximum lift coefficient optimal cross-stream locations from wake centerline. Oscillating could generate periodic with better spanwise cohe...

The aim of this study is to investigate the effectiveness and mechanism wind buffeting noise suppression using a new bionic structure inspired by quiet flight owls. Firstly, schemes based on NACA0012 wing with two sinusoidal leading-edge serrations one straight curve are used in cavity after verifying simulation. Then, results three compared analyzed. It found that surface ridges can suppress e...