The energy conversion performance of several types of Wells turbine designs

Abstract

Several types of single-plane and multiplane Wells turbines are investigated and compared. The turbines’ aerodynamic losses and overall performances are presented and two successful methods of swirl energy recovery are studied in detail. Guide vanes were fitted to a monoplane turbine whereas the rotors of a biplane turbine were contra-rotated. A double-shaft biplane turbine was also tested. The contra-rotating turbine had an operational range which was similar to that of the monoplane turbine with guide vanes, achieved a similar peak efficiency, but performed better in the post-stall region and also was found to be able to accommodate a much higher pressure-flow ratio.

A review of wave energy converter technology

“…The most popular air turbine design is the Wells turbine, because of its ability to rotate in the same direction, irrespective of airflow direction. Inherent disadvantages include low efficiency (around 60-65 per cent [47,48]), poor starting, high noise, and high axial thrust when compared to traditional turbines [49]. Pitch control of the turbine blades can increase efficiency [50].…”

Accurate numerical simulation of a high solidity Wells turbine

“…In order to assess the capability of the numerical solver to properly evaluate the flow through the Wells turbine, the behavior of a high solidity Wells turbine, for which experimental [28] and numerical [25] data are available over a wide range of flow rate, has been studied. The turbine presents the following characteristics:…”

High performance ocean energy harvesting turbine design–A new casing treatment scheme

“…Other efforts involve modification of guide vane angle [15e17], bidirectional flow [18], variable chord [19], bi-plane unidirectional blade [20], counter rotating blade [21,22], hysteretic behavior with unsteady flow [23], etc. In a simpler design, the turbine has limited moving elements but a larger separated zone makes the turbine less efficient.…”