Tidal energy is the most foreseeable form of renewable energy. Tidal energy can be harnessed by tidal barrage, tidal fence and tidal current technologies. Present efforts are focused on diffuser augmented tidal turbines that exploit the kinetic energy of the tidal currents. The power output by a tidal turbine is directly proportional to the cube of velocity of incoming fluid flow. Thus, even a ...

This paper presents numerical analyses of aerodynamics and aeroacoustics ducted/un-ducted propellers based on high-fidelity CFD methods, adjoint-based aerodynamic performance optimisation the ducted propeller by altering duct blade shapes. Ducted experiments NASA are chosen for validation used as baseline designs. High-fidelity simulations performed using in-house solver HMB3. The is analysed s...

The aerodynamic parameters of ducted fan micro aerial vehicles (MAVs) are difficult and expensive to precisely measure and are, therefore, not available in most cases. Furthermore, the actuator dynamics with risks of potentially destabilizing the overall system are important but often neglected consideration factors in the control system design of ducted fan MAVs. This paper presents a near-hov...

Ducted propagation of whistler waves in the terrestrial magnetosphere-ionosphere system was discussed and studied long before the first in-situ spacecraft measurements. While a number of implicit examples of the existence of ducted propagation have been found, direct observation of ducts has been hampered by the low sampling rates of measurements of the plasma density. The present paper is base...

Abstract AeroMINEs consist of a mirrored pair foils that have no external moving parts. A low-pressure region is created between the foils. The are hollow and side skins contain orifices (air-jets) allow air to flow from interior foil exterior flow, driven by suction pair. This ducted an internal turbine generator, producing electricity. series pilot-scale field (1-m chord) demonstrations were ...

Small ducted fan autonomous vehicles have potential for several applications, especially for missions in urban environments. This paper discusses the use of dynamic inversion with neural network adaptation to provide an adaptive controller for the GTSpy, a small ducted fan autonomous vehicle based on the Micro Autonomous Systems’ Helispy. This approach allows utilization of the entire flight en...

This paper presents the performance analysis and a parametric study of equivalent ducted/un-ducted rotors using high-fidelity CFD methods. A model-scale ducted rotor case by NASA was analysed used as initial design. An un-ducted producing same thrust power first derived momentum theory. The configurations were later scaled to support four-rotor vehicle 6,000 kg BEMT model. High-fidelity simulat...

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Abstract The use of ducted configuration to increase the efficiency wind turbine rotors is gaining wide attention in scientific community. Specifically for mini and micro urban environment applications this solution demonstrated be very attractive. possibility overcome Betz limit power coefficient was widely horizontal axis turbines. However, few studies have dealt with Savonius rotor despite t...