  A mathematical model is developed to study the behaviour of an oscillating
wave energy converter in a channel. During recent laboratory tests in a wave
tank, peaks in the hydrodynamic actions on the converter occurred at certain
frequencies of the incident waves. This resonant mechanism is known to be
generated by the transverse sloshing modes of the channel. Here the influence
of the channel sloshing modes on the performance of the device is further
investigated. Within the framework of a linear inviscid potential-flow theory,
application of the Green theorem yields a hypersingular integral equation for
the velocity potential in the fluid domain. The solution is found in terms of a
fast-converging series of Chebyshev polynomials of the second kind. The
physical behaviour of the system is then analysed, showing sensitivity of the
resonant sloshing modes to the geometry of the device, that concurs in
increasing the maximum efficiency. Analytical results are validated with
available numerical and experimental data.
