This paper provides a summary of a Computational Fluid Mechanics (CFD) investigation of the aerodynamic behaviour of linear cascades of blades such as those found in the rotors of axial flow air turbines in Oscillating Water Column (OWC) wave energy devices. The main aim of the work was to provide information on the “interference factor” for lift and drag coefficients on blades in linear cascades, ie the ratio of these coefficients for a blade in a cascade compared to that for an isolated blade. Results are presented first for initial validation work in developing the CFD methodology to accurately model single, isolated aerofoils. The analysis is then extended to examine how the cascade solidity, stagger angle and angle of incidence influence the interference factor. The results of this turbulent, viscous flow analysis are compared to the fundamental inviscid analysis carried out by Weinig [1] and to the limited experimental data available in the literature. The relevance of this work to design of OWC air turbines using conventional blade element analysis methodology is also discussed.
