Methods Used

The methods employed in Hydro for the calculation of manoeuvring characteristics are of the semi-empirical formulation type. The program calculates the hydrodynamic derivatives of the manoeuvring equation, ship resistance, propeller thrust, rudder forces and moments. The differential equations of ship motion in the horizontal planes are solved numerically in the time domain to simulate the ship manoeuvring motion for certain rudder movements.

Alternatively, and if available, you may input his own hydrodynamic derivatives.

A non-linear mathematical model has been used to describe the manoeuvring motion of the ship. The propeller, rudder, steering gear, variation in wake due to sway and yaw, inflow velocity and inflow angle to the rudder have been modelled and integrated with the mathematical model. See Manoeuvring Module for a more detailed discussion of the mathematics involved.