Terminology

Term Definition
Added Mass A(\omega)
BEM Boundary Element Method
BEMIO Boundary Element Method Input/Output
BS Bretschneider Wave Spectrum
$CASE WEC-Sim case directory
Heave (Z) Motion along the Z-axis
JS JONSWAP Spectrum
Pitch (Ry) Rotation about the Y-axis
PM Pierson-Moskowitz Specturm
PTO Power Take-Off
Radiation Damping B(\omega)
Roll (Rx) Rotation about the X-axis
$SOURCE WEC-Sim source code directory
Surge(x) Motion along the X-axis
Sway (Y) Motion along the Y-axis
Wave Excitation F_{exc}
Yaw (Rz) Rotation about the Z-axis

Variables

Variable Definition
A * Wave amplitude (m), A = \frac{H}{2}
A(\omega) Frequency dependent radiation added mass (kg)
A_{\infty} Added mass at infinite frequency (kg)
B(\omega) Frequency dependent radiation wave damping (N/m/s)
C_{a} Morison element coefficient of added mass
C_{d} Quadratic drag coefficient
C_{m} Mooring damping matrix (N/m/s)
C_{pto} PTO damping coefficient (N/m/s)
C_{v} Linear (viscous) damping coefficient (N/m/s)
\eta Incident wave (m)
f Wave frequency (Hz)
F_{B} Net buoyancy restoring force (N) or torque (N.m)
F_{exc} Wave excitation force (N) or torque (N.m)
F_{rad} Wave radiation force (N) or torque (N.m)
F_{pto} Power take-off force (N) or torque (N.m)
F_{me} Morison element force (N) or torque (N.m)
F_{v} Damping or friction force (N) or torque (N.m)
F_{m} Mooring connection force (N) or torque (N.m)
g Gravity (m/s/s)
h Water depth (m)
H Wave height (m)
H_{s} Significant wave height, mean wave height of the tallest third of waves (m)
H_{m0} Spectrally derived significant wave height (m)
k Wave number (rad/m), k = \frac{2\pi}{\lambda}
K_{hs} Linear hydrostatic restoring coefficient (N/m)
K_{m} Mooring stiffness matrix (N/m)
K_{pto} PTO stiffness coefficient (N/m)
\lambda Wave length (m)
m Mass of body (kg)
m_k Spectral moment of k, for k = 0,1,2,…
\omega Wave frequency (rad/s), \omega = \frac{2\pi}{T}
\phi Wave phase (rad)
R_{f} Ramp function
\rho Water density (kg/m3)
t Simulation time (s)
t_{r} Ramp time (s)
\theta Wave direction (Degrees)
T_{e} * Energy period (s)
T_{p} Peak period (s)
X Translation and rotation displacement vector (m) or (rad)

Note

This section is a work in progress, * means may not be used in WEC-Sim doc