A trawl door with an additional, controlled foil.

Collaboration diagram for Trawl door with foil:

Author: Karl-Johan Reite

Date: 09.01.2014 KJR: Initial version.

This simObject represents a trawl door with an additional, controlled foil. It is meant for testing proposed control concepts. The foil is specified by the following parameters: Angle of attack relative to the door, exposed area, angle of roll relative to the door, lift and drag coefficient for several angles of attack.

SThe trawl door is simulated in six degrees of freedom. This model includes a fairly complex model of the hydrodynamic forces and the fastening points of the warp and the bridles. It is based on unit quaternions for translation between different coordinate systems, to avoid the singularity problem of Euler angles.

Example file input:

<Lib LibName                = "fhsim_fishery"
    SimObject               = "trawl/TrawlDoorAddedFoil"
    Name                    = "door"
    />

Configuration parameters

Name	Width	Description
FoilHydro_Aoa	<HydroSpecWidth>	The foil angle of attack relative to the water flow.
FoilHydro_CL	<HydroSpecWidth>	The foil lift coefficient for the specified angles of attack in FoilHydro_Aoa.
FoilHydro_CD	<HydroSpecWidth>	The foil drag coefficient for the specified angles of attack in FoilHydro_Aoa.
FoilHydro_IsVertical	1	Is the foil vertical? Otherwise it is assumed horizontal (in relation to the trawl door).
FoilHydro_Cord	1	The foil cord.
FoilHydro_Span	1	The foil span.

Input Ports

Name	Width	Description
FoilRelativeYaw	1	The foils angle of yaw relative to the door.
FoilRelativeRoll	1	The foils angle of roll relative to the door.
FoilRelativePitch	1	The foils angle of pitch relative to the door.
FoilExposedAreaRatio	1	The ratio of the foils area which is exposed.
FoilRelPosition	1	The position of the foil in the trawl door coordinate system.

Output Ports

Name	Width	Description
FoilEnergyConsumed	1	The energy consumed by controlling the foil.

Initial conditions

Position, orientation

This SimObject is referred to as Trawl/TrawlDoorAddedFoil