# Terminology

The following terminology is used in MHKiT:

Term |
Definition [unit] |
---|---|

\(A_P\) |
Projected capture area [m^2] |

BS |
Bretschneider spectrum |

\(D\) |
Characteristic length [m] |

\(D_E\) |
Equivalent diameter [m] |

DEL |
Damage Equivalent Load |

\(E\) |
Energy [J] |

\(\eta\) |
Incident wave [m] |

\(f\) |
Frequency [Hz] |

\(F\) |
Exceedance probability [%] |

Fr |
Froude Number |

\(g\) |
Gravity [m/s/s] |

\(h\) |
Water depth from bottom to water surface (e.g. SWL) [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] |

\(J\) |
Wave energy flux [W/m] |

JS |
JONSWAP spectrum |

\(L\) |
Capture length [m] |

\(\lambda_w\) |
Wave length [m] |

\(k\) |
Wave number, \(k = \frac{2\pi}{\lambda_w}\) [rad/m] |

KC |
Keulegan-Carpenter number |

\(m\) |
Mass [kg] |

\(m_k\) |
Spectral moment of k, for k = 0,1,2,… |

\(\omega\) |
Wave frequency, \(\omega = \frac{2\pi}{T}\) [rad/s] |

\(P\) |
Power [W] |

PM |
Pierson-Moskowitz spectrum |

\(Q\) |
Discharge [m^3/s] |

\(\rho\) |
Density [kg/m^3] |

\(S\) |
Spectral density [m^2/Hz] |

SWL |
Still water line |

\(T_{e}\) |
Energy period [s] |

\(T_{m}\) |
Mean wave period [s] |

\(T_{p}\) |
Peak period [s] |

\(T_{z}\) |
Zero-crossing period [s] |

\(u\) |
Voltage [V] |

\(v\) |
Velocity [m/s] |

\(V\) |
Velocity calculated for river and tidal modules [m/s] |

## Units

The methods in MHKiT use the MKS (meters-kilograms-seconds) system, and assume data is stored in SI units, for example:

Acceleration = \(m/s^2\)

Current = \(A\)

Distance = \(m\)

Energy = \(J\)

Frequency = \(Hz\)

Mass = \(kg\)

Power = \(W\)

Pressure = \(Pa\)

Time = \(s\)

Velocity = \(m/s\)

Voltage = \(V\)

Volume = \(m^3\)