I wanted to know what was the best solution to define a T-foil with the wing being one flap ? In other words, you can move the whole wing with the actuator to change the AoA.
At first I thought that the easiest solution was to define the hinge position in XFLR-5 very close to the leading edge but the X-foil tool of the simulator can’t converge despite my multiple tries.
Then I thought of the (hypothetical) idea of defining the wing and the strut as 2 separate foil elements. I would define the wing, instead of in the body reference frame, in the strut reference frame.
I would then define a horizontal bearing element for the wing so that it can be actuated. As it would be define in the strut reference frame, I think that the wing will be able to turn when the strut will turn (in the case of the strut being the rudder element of the boat)
For now, I decided that the simplest solution was to just add rake to the T-foil element but it is not very close to the reality.
The best solution is to use the ‘SpanwiseElementRotation’ parameter to define the spanwise roation angle of each element, in degrees. The ‘SpanwiseElementRotation’ requires the ‘HasSpanwiseElementRotationInput’ to be set to true. Please see the documentation in section Blocks Reference / Foilboc for more detail. Here is an example:
"WingRotation" : BL.State({ Init : 5, Min : -10, Max : 10, Optimise : true }),
"SpanwiseElementRotation" : [0, "-{WingRotation}*", "{WingRotation}*"],
"Rudder" : BL.Foilboc({
"Inputs" : {
FoilExtDot : 0,
FoilYawDot : 0,
FoilCantDot : 0,
FoilRakeDot : 0,
SpanwiseElementRotation : "{SpanwiseElementRotation}",
},
HasSpanwiseElementRotationInput : true,
...
)},
Please note that if your T-foil is symmetrical, you can define its geometry using the T-Foil-Symmetrical template available from the GUI in the Foil -> Templates menu. Also, the Rudder02 of the Gomboc 60 project sample is a symmetrical T-rudder and shows which symmetry can be used in the *.bic file.