Abstract
WEC-Sim is a midfidelity numerical tool for modeling wave energy conversion devices. The code uses the MATLAB SimMechanics package to solve multibody dynamics and models wave interactions using hydrodynamic coefficients derived from frequency-domain boundary-element methods. This paper presents the new modeling features introduced in the latest release of WEC-Sim. The first feature discussed is the conversion of the fluid memory kernel to a state-space approximation. This is a substantial computational benefit after the hydrodynamic body-to-body coefficients are introduced and the number of interactions increases exponentially with each additional body. The final features to be introduced is the ability to calculate the wave excitation forces based on the instantaneous incident wave angle allowing the device to weathervane and importation of a user defined wave elevation time series. A review of the hydrodynamic theory for each feature is provided and successful implementation is verified using test cases.