Vertical axis wind turbine blades undergo dynamic stall due to the large 1 angle of attack variation they experience during a turbine rotation. Particle image 2 velocimetry on a pitching and surging airfoil was used to perform time resolved 3 measurements at blade Reynolds numbers near turbine operating conditions of 105. 4 These experiments were compared to simulations performed in the rotatin...

We carried out direct numerical simulations of the flow past a two-dimensional S822 wind turbine blade section at a chord Reynolds number of Re=100,000 and an angle of attack of α = 5deg. Without blade rotation the separated boundary layer “rolls up” into spanwise vortices which then “break up” into smaller scale structures leading to transition to turbulence. Simulation results compare favorab...

The Axial compressor is an integrated part of a gas turbine. The central part of compressors is its blades. Blade aerodynamic has a significant effect on compressor performance. Because of the adverse pressure gradient in the compressor, any deviation in the blade profile has a significant influence on the flow field as well as the compressor performance. During the manufacturing and operation ...

In this study, the behavior of a subject consisting of a cylinder with 4 plates perpendicular to it with a rotational degree of freedom under airflow both through the numerical approach, known as improved discrete vortex and experimental approach were investigated. The experimental and numerical results have shown that oscillating regime occurs in low velocity and length. This movement is vibra...

A detailed review of the current state-of-art for wind turbine blade design is presented, including theoretical maximum efficiency, propulsion, practical efficiency, HAWT blade design, and blade loads. The review provides a complete picture of wind turbine blade design and shows the dominance of modern turbines almost exclusive use of horizontal axis rotors. The aerodynamic design principles fo...

  Background: There are few studies comparing the biomechanical properties of angled blade plate and locking compression plates in supracondylar osteotomy. In the current randomized study, we prospectively compared the clinical and radiological outcomes of supracondylar osteotomy using these two plates. Methods: Forty patients with valgus knee malalignment were randomly assigned to two equal nu...

Focusing on the tip leakage vortex cavitation, experimental and numerical studies were carried out as the first step of the investigation of cavitations in tip leakage flow. For a single hydrofoil with a tip clearance, tip leakage vortex cavitations were observed for various cavitation numbers and angles of attack. To simulate the tip leakage vortex cavitation, a simple calculation of 2-D unste...

A numerical procedure was developed to determine a variable-pitch law that maximized the performance of vertical-axis wind turbine (VAWT). The methodology based on determination, for each blade, angle attack maximizing stationary aerodynamic efficiency at prescribed azimuthal positions. angles were determined by means panel method with low computational effort, and implemented in Matlab® softwa...

The availability of non-renewable energy has recently been running low and so impacts electrical energy. Renewable is converted from natural sources to kinetic Double Propeller Water Turbine a water turbine that suitable be applied using small flow head. This research development previous by changing the degree inclination blade angle on turbine, which used determine changes in power efficiency...