Hysteretic characteristics of monoplane and biplane Wells turbine for wave power conversion

Accurate numerical simulation of a high solidity Wells turbine

“…In particular, threedimensional numerical simulations were carried out by Thakker et al [20] in order to provide the performance of a Wells turbine with CA9 blade profile, by Kim et al [21] in order to study the effect of the blade sweep on the performance of a Wells turbine using either NACA0020 or CA9 blade profiles, and by Dhanasekaran and Govardhan [22] in order to investigate the characteristics of a Wells turbine with NACA0021 constant chord blades. Recently, hysteretic phenomena have been detected under oscillating flow conditions [23][24][25], especially when the oscillating flow amplitude grows. This work aims at providing a detailed description of the flow-field through a high solidity Wells turbine using blades with constant chord NACA0015 profiles.…”

Wells turbine for wave energy conversion: a review

“…A CFD model of W-T is used to investigate the hysteretic behavior in [75]. Numerical simulations are conducted for the hysteretic behavior of monoplane and biplane W-Ts in [80][81][82]. In order to investigate the mechanism of the hysteretic behavior of W-T and also the effect of solidity, setting angles and blade thickness on the hysteretic behavior of W-T (where the setting angle is defined as an angle between the blade chord line and the rotational direction of rotor, ω R m ), CFD simulations are conducted for the flow field around a blade of a W-T by [76,77].…”

“…The experimental work is performed at a test rig capable of producing reversing air flows. Many of CFD investigations employ this experimental work as a validation case such as T. H. Kim, et al [76,113] and Zahari Taha, et al [139,140], in addition to several other CFD works in [77,81,82,129,134,135]. The piston can be driven back and forth by means of three ball screws acted upon by a DC servomotor.…”

“…It is found that all turbines have similar hysteretic loops; however, the hysteresis characteristics of the W-T are less sensitive to the blade profile than to solidity, setting angles, and blade thickness. Numerical simulations are conducted for the hysteretic behavior of monoplane and biplane W-Ts in [80][81][82]. It is found that for the monoplane W-T, the hysteretic loop is opposite to the well-known dynamic stall [83][84][85][86][87][88] of an airfoil.…”

Direct AC–AC grid interface converter for ocean wave energy system

“…An OWC is an air chamber with an opening below the water level and has an air outlet through a turbine at the top. The incoming waves cause the water level inside the chamber rises and falls and the oscillating air pressure inside the chamber can drive a turbine at the top for electricity production [9]. Apart from using turbine, a linear generator was also proposed to convert wave kinetic energy directly into electricity [10].…”