Abstract A numerical investigation has been conducted on the ram-rotor with various blade-to-blade profiles to achieve potential benefits in enhancing their performance. The profile is changed by adjusting strake camber line enable formation of expansive and contractive flow paths. Results indicate that path can significantly improve total pressure ratio altering position shock trains. Subsonic...

Title of Dissertation: A Coupled CFD/CSD Investigation of the Effects of Leading Edge Slat on Rotor Performance Asitav Mishra, Doctor of Philosophy, 2012 Dissertation directed by: Associate Professor James D. Baeder Department of Aerospace Engineering A coupled Computational Fluid Dynamic (CFD) and Computational Structural Dynamics (CSD) methodology is extended to analyze the effectiveness of a...

The paper describes an observer capable of detecting the impingement on a wind turbine rotor of the wake of an upstream machine. The observer estimates the local wind speed and turbulence intensity on the left and right parts of the rotor disk. The estimation is performed based on blade loads measured by strain gages or optical fibers, sensors which are becoming standard equipment on many moder...

The paper describes an unusual C beam discretization based on the finite volumes concept. The formulation is developed in the linear (linearised) case first; eventually a non-linear multi-body approach to the same problem, based on previous works [9], is presented. The formulation is generalised to the piezo-electric beam in both cases, with reference to work [10]. Some applications are outline...

Abstract Multi‐rotor floating wind turbines are among the innovative technologies proposed in last decade effort to reduce cost of energy. These systems able offer advantages terms smaller blades deployed offshore, cheaper operations, fewer installations, and sharing platform. As blade‐pitch actuation system is prone failures, assessment associated load scenarios commonly required. Load fault h...

At the most fundamental level, main rotor loading noise is caused by the harmonically-varying aerodynamic loads (acoustic pressures) exerted by the rotating blades on the air. Rotorcraft main rotor noise is therefore, in principle, a function of rotor control inputs, and thus the forces and moments required to achieve steady, or “trim”, flight equilibrium. In certain flight conditions, the ensu...

In above rated conditions, wind turbines are often subjected to undesirable high structural loading. We investigate two feedback control techniques in combination with a feedforward control method for reducing blade flap bending loads in above rated wind conditions. The feedback controls studied include both disturbance accommodating/tracking and integral augmented/repetitive types that incorpo...

The value of adding adaptive blades to a variable speed turbine is studied by applying a general purpose optimization scheme to a baseline turbine configuration. The turbine is the AWT-26. Adaptive-blade effects involve elastic twist coupling tied to centrifugal and flap loadings. Two baseline variable speed approaches are examined. In the “aggressive” approach the speed control is assumed to l...

An approximate numerical mthod is presented for analysis and determination of modal characteristics in straight, pretwisted non-unifom helicopter blades. The analysis considers the coupled flapwise bending (out of plane), chordwise bending (in plane), and torsion vibration of both rotating and non-rotating blades. The proposed method is based on the integral expansion of Green functions (struct...