jjn9128 wrote: ↑
Mon May 02, 2022 8:26 am
I'm not quite sure why the flap would need more definition than the mainplane if the tangency tension and direction of the flap splines is the same as the mainplane?
So bearing in mind, my whole goal/motivation for this whole exercise is mainly just about improving my CAD skills and wanting to imitate and impliment many real-world examples where plausable of certain features and the rear wing itself is more focused towards an aesthetic point of view once I put it in Keyshot and do some renders, rather than trying to make a wing with the best downforce to drag ratio, I hope I can explain myself well.
So, from the screenshot below, the purple surfaces are not explicitly defined by any profile or chord lengths etc, as its just a through-curves-mesh surface using splines to connect the two mainplane and flap profiles that are explicitly defined to create the yellow extruded surfaces, making sure spline tangency is identical for each side.
Now, if I was to add a slot gap separator where the teal plane intersects the purple surfaces, the flap should have a V-shop notch as you obviously know, the separator will cause the flow to separate earlier along the flap's suction side, using this Ferrari wing as an example.
The easy quick and dirty way, would be to extrude the V shape normal to the X axis and then use it to split it from the flap, but obviously that isn't what F1 teams are doing, as that method will be truncating the sharp trailing edge in that area. Instead, that notch in the flap is created by having a shorter flap chord where the slot gap intersects the wing (ie the teal plane from my model screenshot), with the trailing edge of the shortened chord transitioning back to the original flap trailing edge in between the two green planes in the screenshot below.
But then the problem is, the cross section of the purple surface along the Y axis is always changing, meaning the mainplane and flap profiles are always changing, and since the sections in that area are not defined by their own sketches, to create the notch while maintaining that smooth uniform transition defined by the spline tangencies, a shortened flap chord needs to be defined at the teal plane, with it's chord and trailing edge increasing either side by the time it gets to green planes.
But the trailing edges of the purple surfaces are defined implicitly from the splines, which as a result, the chord legnths of that section are also defined implicitly as a result of the sweep/loft that is created between the two profiles I have explicitly defined with sketches as shown below.
I really hope I explained my point across properly without confusing you, I also know the flap profiles aren't the best, as my method doesn't work well it seems with smaller chords and is a lot more trial and error and I rushed it quickly just to get this reply up with screenshots to better explain