Extends Propeller4Q.

Collaboration diagram for Propeller 4Q with strut:

A Propeller 4Q with a strut (a low aspect ratio foil that carries the propeller). The object has all the input ports, output ports and configuration parameters of Propeller4Q. In addition it computes the lift and drag of the strut from the cross-flow: the strut sits at half of StrutHeight along the body z axis from the propeller, the velocity relative to the water (without the jet of the propeller) is taken in the body xy plane, the angle of attack \( \alpha = \arcsin(v_y/|v|) \) is read in a built-in table of \( C_l \) and \( C_d \) (linear interpolation, last value held above \( \pi/2 \) ), and \( L = \frac{1}{2}\rho C_l c\, h\, |v|^2 \), \( D = \frac{1}{2}\rho C_d c\, h\, |v|^2 \) with \( c \) = StrutChord and \( h \) = StrutHeight. There is no strut force when the relative velocity is zero or when the test P.z() < h on the strut point and the surface elevation \( h \) holds.

Output ports (in addition to those of Propeller4Q)

Name	Width	Description
Force2NED	3	ForceNED of the propeller plus the force of the strut
ForceCorrected2NED	3	ForceCorrectedNED of the propeller plus the force of the strut
Force2Body	3	ForceBody of the propeller plus the force of the strut in the body frame
ForceCorrected2Body	3	ForceCorrectedBody of the propeller plus the force of the strut in the body frame
StrutAngleOA	1	Angle of attack of the strut in radians
StrutCL	1	Lift coefficient of the strut
StrutCD	1	Drag coefficient of the strut

Configuration parameters (in addition to those of Propeller4Q)

Name	Width	Description
StrutHeight	1	Height \( h \) of the strut. Required. Unit not stated in the code
StrutChord	1	Chord \( c \) of the strut. Required. Unit not stated in the code