Ship Detailed Settings

With Hafenskipper 2 you can configure many characteristics of the ship models.  You can match the ship models to match a specific ship or experiment and understand the influence of the ship characteristics. The following settings are available:

1.1 PowerSingle engine power kW
1.2 MassMass of the ship Kg
1.3 Engine TypeEngine types selectable are depending on ship: Outboard, single or twin engine Stationary shaft, single or twin engine Sail drive 
1.4 RudderNumber of rudders 
1.5 Propeller RotationRight hand / Left handTwin engine: inwards / outwards 
1.6 Prop WalkStrength of propeller walk %
1.7 Rudder SizeIncreased rudder size means greater rudder forces. This parameter only influences the rudder force due to the speed through the water.%
1.8 Prop WashStrength of the rudder forces due to propeller wash.%
1.9 Max. Rudder AngleMaximum rudder deflection angle to left and to right side. °
1.10 Steering Wheel TranslationTranslation between steering wheel and rudder angle.1
1.11 Moment of Inertia (Yaw) Kg * m² 
1.12 Power  Bow Thruster kW
1.13 Wind ResistanceResistance of the ship to cross winds. Resistance to head wind is changed in relation. %
1.14 Wind Center of EffortLongitudinal offset of the side wind center of effort. m
1.15 Size of Lateral planSize of the lateral projection of the underwater ship.%
1.16 Center of Lateral Resistance Longitudinal offset m

When percent (%) is stated as the unit, the parameter is adjusted relative to the standard value for each individual ship. In the following you can find an explanation of all parameters in detail:

1.1 Power

This parameter sets the main engine power. With a twin-engine ship this is the power of a single engine. 

1.2 Mass

The mass of the ship can be adjusted within reasonable limits. 

1.3 Engine type

Choose the drive type depending on the selected ship:

  • Outboard motor, single or twin engine
  • Stationary shaft drive, single or twin engine 
  • Sail drive
1.4 Rudder

With some ship models you can choose between one or two rudders. To take advantage of the propeller wash for steering at low speeds, you need to match the number of rudders to the number of propellers. 

1.5 Propeller Rotation

Select the rotation direction of the propellers. Choose between right-handed and left-handed propellers. For a twin engine ship the propellers usually have opposite directions. In this case you can also choose inward or outward rotation.  

A right-handed propeller turns clockwise when driving forward and as seen from behind the ship looking towards the propeller. 

Two propellers turn inward, when the left propeller is right-handed and the right one is left-handed.

1.6 Prop walk

Strength of the propeller walk. The direction of the propeller walk is set by the propeller rotation direction above.

The parameter is set relative to the ship default values (see also: propeller walk).

1.7 Ruder size

Change the ruder size to adjust the magnitude of the rudder force due to the speed through the water. The parameter is set relative to the ship default values.

To set the rudder force due to propeller wash, modify the “prop wash” parameter.

1.8 Prop wash

Adjust the strength of the rudder forces due to propeller wash.

The parameter is set relative to the ship default values.

1.9 Max. Rudder Angle

Set the maximum rudder deflection angle from 0° to either side. The rudder range is twice this value.

1.10 Steering Wheel Translation

Set the translation between steering wheel angle and rudder angle.

1.11 Moment of Intertia (Yaw)

Set the resistance of the ship body against an angular acceleration around the yaw axis.

1.12 Power Bow Thruster

Set the power of the bow thruster engine. 

1.13 Wind Resistance

Set the ship wind resistance. The parameter modifies the resistance to crosswind and proportionally as well the resistance to headwind. 

The value is set relative to the ship default values for cross- and headwinds. 

1.14 Wind Center of Effort

The wind not only moves the ship along the wind direction but it can also turn the ship. 

For this we look at the wind center of effort. This is the point at which the wind force acts upon the ship. The location of this point is approximately the centroid of the surface Awexposed to the wind. (see figure below).

When the wind center of effort CEis located away from the center of gravity CGof the ship towards the bow, the bow is blown away from the wind (leeward) If the center of effort is located towards the stern, the bow is turned windwards.

With this parameter you can set the longitudinal offset CEoffs,xof the center of effort relative to the center of gravity. Setting a positive value moves the center of the effort towards the bow. 

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Figure: Wind Center of Effort
1.15 Size of Lateral Plan

The lateral plan is the lateral projection of the underwater ship. This is the surface of the underwater ship you see when looking from the side. (see figure below).

The greater the area AUWof the lateral plan, the higher the ship will resist a lateral drift through the water. 

The value is set relative to the ship default value. The default for a yacht with keel is much higher than for a motor boat.

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Figure: Size of Lateral Plan
1.16 Center of Lateral Resistance

When the ship is drifting sideways through the water, a resistance force acts on the ship underwater body. Analog to the wind center of effort, the center of lateral resistance is the point where the resistance force is applied. The center of lateral resistance is approximately at the centroid of the lateral plan. 

If the center of lateral resistance CLRis not at the center of gravity CG, a momentum will cause the bow of the ship to turn.

You can set the longitudinal offset CLRoffs,xof the center of lateral resistance relative to the center of gravity. Setting a positive value will cause the bow to be pushed in the direction opposite to the drift. 

The contribution of the rudder is adding up to the momentum causing the ship to turn. This contribution changes when you adjust the rudder size parameter.