This paper presents an experimental investigation of CA9 rotor Wells turbine. The experimental rig is 0.3m in diameter and tests are carried out at Re= lxl0 s and Ma= 0.1. The blades are of constant chord and rectangular in shape. Tests are carried out at two solidities: 0.48 and 0.6 respectively. The aim of this work is to investigate and compare the aerodynamic characteristics of the newly developed CA9 profile with other commonly used NACA series profdes. It was expected that the new prof'de would be more resistant to stalling and show a wider range of high efficiency operation. Results show that enhanced resistance to stall is not detected. The results would suggest more work to be done on a bigger diameter rig where aerodynamics forces and characteristics would predominate.
Since the fossil oil crisis in the 70's, much focus has been laid on alternative renewable sources of energy such as ocean waves. Several different principles for wave power extraction had been developed and one of the most successful was found to be the Wells turbine coupled to an oscillating water column (OWC) to generate electrical power. The Wells turbine is a self-rectifying axial flow air turbine. It produces unidirectional rotary motion from a reciprocating flow. The Wells turbine is fitted with symmetrical blades which are set radially at a 90° angle of stagger. Since its invention in 1976 by Dr. A.A.Wells, most researchers have focused on improving its efficiency and its range of efficient operation. In fact, compared to other air turbines (e.g. Francis turbine) the Wells turbine has lower efficiency and range of operation but it can extract power at low airflow rate, where other turbines would be inefficient.
