This paper presents the flow fields and aerodynamic loading of a two bladed H-type vertical axis wind turbine with active variable pitch for load circulation control. Particle Image Velocimetry is used to capture at six azimuthal positions blades during operation, three upwind downwind. Flow phenomena such as dynamic stall tower shadow are captured in fields. The phase-averaged velocity their t...

The paper describes a formulation for aeroelastic analysis of aircraft with high-aspect-ratio wings. The analysis is a combination of a geometrically-exact mixed formulation for dynamics of moving beams and finite-state unsteady aerodynamics with the ability to model dynamic stall. The analysis also takes into account gravitational forces, propulsive forces and rigidbody dynamics. The code has ...

In the aero-elastic analysis of wind turbines based on blade element theory, the need to include a model of the local, two-dimensional instationary aerodynamic loads, commonly referred to as dynamic stall has become obvious in the last years. In this contribution we describe an alternative choice for such a model, based on [19]. Its derivation is governed by the flow physics, thus enabling inte...

Modern wind turbines usually suffer unexpected power losses after long operating periods due to the contaminations accumulated at the leading edge of blades. In order to investigate the underlying physics, experiments were conducted to study the performance degradation of low-Reynolds-number airfoils induced by distributed leading edge roughness. Roughness was simulated by precisely manufacture...

The use of Active Flow Control (AFC) technologies to modify the forces acting on streamlined bodies is one most active research fields in aerodynamics. For each particular application, finding optimum set AFC parameters which maximises lift, minimises drag or lift-to-drag ratio (aerodynamic efficiency), has become a necessary design requirement. In present paper, technology was applied Selig-Do...

Vertical-axis wind turbines (VAWT) are excellent candidates to complement traditional and increase the total energy capacity. Development of VAWT has been hampered by their low efficiency structural unreliability, which related occurrence dynamic stall. Dynamic stall consists formation, growth, shedding large-scale vortices, followed massive flow separation. The vortex is detrimental turbine's ...

The purpose of this paper is to analysis the basic aerodynamic theory of wings and the provide an introduction to wind tunnel testing. This is followed by the result from the wind tunnel testing of a NACA4412 and the analysis of the data. Lift increase at the angle of attack increase at certain point and at this point it become maximum. After that if the angle of attack is increased by further,...

Considering the dynamic stall effects in engineering calculations is essential for correcting aerodynamic loads acting on wind turbines, both during power production and stand-still cases, impacts significantly turbine aeroelastic stability. The employed model needs to be accurate robust a wide range of airfoils angle attack. present studies are intended demonstrate performance recently impleme...