Blade-tip vortices and their interaction with the helicopter blades play an important role in the generation of noise on rotorcrafts. Full-scale vortex visualization is essential for the understanding of these effects and the validation of sub-scale experiments and numerical simulations. In the present work, the reference-free Background Oriented Schlieren (BOS) method was used to visualize bla...

Two major barriers to widespread US acceptance of offshore wind energy is reliability of rotor blades and the difficulty to access for inspection and maintenance. This work presents operation and design strategies aimed to increase blade reliability and maximize power production. Operating strategies that prolong blade life while optimizing energy output allow for smarter maintenance planning a...

In this paper non-synchronous vibration (NSV) of a GE axial compressor is simulated using a fully coupled fluid/strcuture interaction (FSI). Time accurate NavierStokes equations are solved with a system of 5 decoupled structure modal equations in a fully coupled manner. A 3rd order WENO scheme for the inviscid flux and a 2nd order central differencing for the viscous terms are used to resolve n...

The accumulation of contaminating materials on the rotor blades of a gas turbine flowmeter is a condition of concern to the manufacturers, since it can lead to loss of calibration. Over time, a deposit of tar and heavy oil mixed with sand and dust can build up on the rotor blades, which causes the meter factor to change from its original value of calibration. A novel neural-network technique is...

The article investigates the numeric simulation of two-way aeroelastic processes applied to the experimental phase of a compressor; physical, mathematical, rigid and grid models of the system “gas – rotor – stator” have been worked out; 2 FSI (two-way Fluid-Structure Interaction) calculations have been performed on the evaluation of the interaction between a gas-dynamic flow and a deformable ro...

This paper presents a novel model of large-size tilt-rotor aircraft, which can operate as a helicopter as well as being capable of transition to fixed-wing flight. Aerodynamics of the dynamic large-size tilt-rotors based on blade element method is analyzed during mode transition. For the large-size aircraft with turboshaft engines, the blade pitch angles of the rotors are regulated to vary acco...

This paper presents the aerodynamic design and economical evaluation of a 200 kW site specific wind turbine for the province of Semnan in Iran. By designing site specific wind turbines, the cost of energy which is calculated out of the annual energy production and also the cost of manufacturing the rotor are minimized. The aerodynamic design is based on the well-known blade element momentum...

This paper studies the load reduction potential of a prototyped “smart” rotor. This is, a rotor where the blades are equipped with a number of control devices that locally change the lift profile on the blade, combined with appropriate sensors and controllers. Experimental models, using dedicated system identification techniques, are developed of a scaled rotating two-bladed “smart” rotor of wh...

As the wind turbine size has been increasing and their mechanical components are built lighter, the reduction of the structural loads becomes a very important task of wind turbine control in addition to maximum wind power capture. In this paper, we present a separate set of collective and individual pitch control algorithms. Both pitch control algorithms use the LQR control technique with integ...