A computational study of helicopter vibration and rotor shaft power reduction is conducted using activelycontrolled trailing-edge flaps (ACFs), implemented in both single and dual flap configurations. Simultaneous vibration reduction and performance enhancement is demonstrated under level flight condition at high advance ratios, where dynamic stall effects are significant. Power reduction is ac...

The double-blade half-rotating impeller tidal turbine (DHITT) is a new type of vertical shaft current with lift and resistance performance. power coefficient the DHITT affected by flow direction. In order to research ( C P ) under different direction, optimal attack angle half-impeller was explored, fluctuation operating at yaw analyzed based on angle. unsteady simulated overlapping grid techni...

This article describes an experimental investigation of the aerodynamic interaction that occurs between distributed propellers in forward flight. To this end, three were installed close proximity a wind tunnel, and changes their performance, flow-field characteristics, noise production quantified using internal force sensors, total-pressure probes, particle-image velocimetry (PIV), microphones ...

Improving the efficiency of compressors has been one of the most important goals of researchers over the years. In this paper, three different methods are presented for parameterization and blade optimization of axial flow compressor. All methods consist of flow analysis tool, optimization algorithms, and parametric geometry generation tool, that are different in each approach. Objective functi...

An extensive experimental investigation to study the flow structure over the wing of a fighter type configuration model has been conducted. The model used for this study was similar to the High Alpha Research Vehicle (HARV) that has been used in various European research centers for studying its force and moment characteristics. Tests were conducted at two subsonic speeds and at low to moderate...

This paper examines the importance of load phase angle variations with respect to fatigue damage. The operating loads on a generic three bladed up-wind 1.5-MW wind turbine blade were analyzed over a range of operating conditions, and an aggregate probability distribution for the actual phase angles between the peak in-plane (lead-lag) and peak out-ofplane (flap) loads was determined. Using a fi...

Wind turbines face harsh inflow conditions when operating in the atmospheric boundary layer or wake of other wind turbines. The incoming velocity field can change within seconds due to turbulent structures it contains, resulting a rapid several degrees angle attack for rotating blade. Aerodynamics are hence rapidly altered, leading changes occurring forces on rotor. Such dynamic cause blades tw...

The reduction of wind turbine blade loads is an important issue in the reduction of the costs of energy production. Reduction of the loads of a non-cyclic nature requires so-called smart rotor control, which involves the application of distributed actuators and sensors to provide fast and local changes in aerodynamic performance. This paper investigates the use of synthetic jets for smart rotor...

The study of vibration response of a turbine blade helps to detect the crack presence in the blade which alters its dynamic characteristics. The change is characterized by changes in the modal parameters associated with natural frequencies. In this paper, study of vibration response is made for turbine blade in the presence of a crack like defect. Turbine blade is initially assumed as a cantile...