[PDF] Top 20 Design and testing of a contra-rotating tidal current turbine

... In predicting the performance of a contra-rotating pair of rotors, certain assumptions must be made. In this study, it was assumed that the rotors are in close proximity, and function as a single actuator ... See full document

... model turbine was then constructed for tank ...When testing, the submerged section of the beam was fitted with a streamlined fairing to reduce pressure build-up and drag; Figure 7 gives a clearer view of ... See full document

... metals testing from self-fabricated eddy current ...metal testing with identical artificial defect and were tested to find its optimal ...of testing from the dual sensor then compared to ... See full document

... Figure 6 and Figure 7 306 show the rotor thrust at each carriage speed as a function of TSR, and Figure 8 and Figure 9 show the rotor torque at each carriage 307 speed as a function of T[r] ... See full document

... wind turbine called the Swept Twist Adaptive Rotor (STAR) blade aiming to improve annual power production from low wind velocity sites (Ashwill et ...parametric design of the STAR blade, an aero elastic ... See full document

... As illustrated in both Figure 10 and Figure 11, the amplitude of the thrust fluctuations was higher for the turbine with composite BT blades than for the turbine with rigid aluminum blades. The fluctuations ... See full document

... The authors acknowledge support from SuperGen UK Centre for Marine Energy (EPSRC: EP/N020782/1) and MaRINET II Transna- tional Access Program. The authors would also like to thank the staff members at INSEAN for their ... See full document

... the design of scale model tests, as geometric and kinematic (fluid and velocity ratios) scaling are more easily done ...for tidal turbines, as it considers fully submerged devices, but is almost impossible ... See full document

... vertical turbine tail as seen in Figure 1 which was found during testing to be ...normal contra-rotating operation (Figure 2) differs significantly from single rotor operation in Figure 3 ... See full document

... ESRU turbine which follows from minimising reactive torque of the supporting system is the reduction of swirl in the ...marine current turbines within tidal farms progresses: namely, the influence of ... See full document

... original design necessitated the boring of a hollow drive shaft to allow the use of two concentric shafts (one from each rotor); unfortunately local manufacturing capacity was limited due to a large demand for ... See full document

... The support structure model is shown in Figure 10, which was based upon SeaGen’s design. The model consists of a 30 m high, 3 m diameter monopile that pierces the water surface, with a crossbeam at a height of 15 ... See full document

... as rotating fra ...is rotating fra me (non inert ia) [2], in order to analyze relat ive velocity impact to a rotor and e xposed current flo w behind the rotor (wake ) ... See full document

... the turbine microcontroller to regulate the overall turbine speed and attain maximum Cp throughout the tidal ...The contra-rotating prime mover torque balance critical to maintaining ... See full document

... Option B – utilises a single generator (IG or PMG) and a single epicyclic differential gearbox where the central sun-wheel is connected to the front rotor and the annulus ring is connected to the rear rotor. The output ... See full document

... It turns out that if we were to insist on having a perfect sinusoidal flux density waveform, we would have to distribute the coils of one phase in a smoothly varying sinusoidal pattern over the whole periphery of the ... See full document

... resources, tidal current energy can be used to generate power without occupying fresh water and land, which is a huge benefit over others ...from tidal currents, a tidal current power ... See full document

... steam-turbine rotating system using theoretical modeling and a simulation combined with experimental condition monitoring and diagnostics ...the rotating system with the toothed-wheel coupling was ... See full document

... the turbine components (blades and tower) is an important parameter when analyzing the rotor performance and structural behavior of the turbine during ...the turbine blades with digital image ... See full document

... asymmetry in the performance characteristics as a blade passes the support structure can be identi fi ed through the velocity contour plot (Fig. 11) which was taken in the horizontal plane, 3 m above the axis of the ... See full document