  The study examines the influence of a sloping porous bed on the efficiency of
an oscillating water column (OWC) device facing oblique water waves. A
vertical, surface piercing, thin plate near a rigid wall approximates the OWC.
The system is simulated using a multi-domain boundary element method assuming
the linear potential theory. The impact of varying sloping bed structural
parameters and influence of the incident wave angle on the performance of the
OWC is evaluated and discussed. The significance of this model to act as a
breakwater protecting near-shore marine facilities is also highlighted. The OWC
efficiency is found to be highly sensitive to the slope of the porous seabed,
and seabed porosity is found to stabilize the resonant frequency against
changes in water levels. OWCs are found to be more efficient over porous
seabeds with higher frictional coefficients. The results indicate optimum
values for the parameters governing such a wave energy conversion system that
can be used for the design and implementation of the model.
