Ocean waves are composed of waves with different frequencies and directions. The waves from different directions interact and cause wave conditions to be very difficult to model mathematically. Various simplified theories and wave spectral models of ocean waves are introduced in the literature, such as small amplitude linear Airy wave, higher order Stokes wave, and irregular waves represented by wave spectra.

Aqwa can simulate first order (Airy wave) and second order (2nd order Stokes wave) regular waves in deep and finite depth water. Additionally, unidirectional or multi-directional irregular waves can be modeled by using the linear superposition approach.