ahmedshafie wrote: ↑23 Jan 2021, 04:37
yea i want to know about profiles ,how 1 element is divided into sections ? , how they designed multi element ?
i made multi element using javafoil for trial and error then made cfd , does that what f1 teams do ?
i want also know about the guide curves , i found that one curve (top view) responsiple for outwash , the other curve (front view) responsible for up wash ,
is there dihedral angle ?
Okay each team will have a slightly different process (disclaimer I don't work at a team but have had conversations with people who do). If you look up aerofoil/airfoil parameterization there are a bunch of methods, but a wing profile can essentially be split into:
- chord - how long the profile is
- camber - how curved the profile is
- thickness - how thick the profile is at it's widest point
- incidence - the angle of the chordline to some fixed reference, either the car reference plane or the preceding wing profile's chordline
- leading edge radius - how blunt/sharp the leading edge is to prevent leading edge stall
- trailing edge thickness - how thick the finite trailing edge is (both for manufacture and CFD best practice)
- leading edge angle - the angle the leading edge deviates from the chordline
- trailing edge angle - the angle the trailing edge forms with the chordline
- trailing edge fishtail - the angle formed between the pressure and suction surfaces as they re-join at the trailing edge
- leading/trailing edge offset - the gap between the leading/trailing edge points and the chordline (but this isn't a necessary parameter).
Rather than having some mathematical model (like the NACA 4/5/6 digits) to determine all these parameters, teams will have a geometric (CAD based) method of forming the wing profiles. Those parameters will be in spreadsheet form so the wing can be generated from variables and so that some method of machine learning could be used to optimize the wing. You then define all those parameters for up to 5 wing profiles as well as defining the slot which is split into:
- slot gap - the minimum distance between sections
- slot overlap - the distance between the trailing edge of the lower wing and leading edge of the upper wing
for the 4 slots between profiles. The wing is then split into sections across the span, using a bare minimum of 4 planes parallel to the car centreline, where the 5 wing profiles and their respective slots are defined. The shape of the wing across the span needs to do different things, i.e. at the Y250 junction there wants to be enough load to generate a vortex but not so much load that the vortex will burst, it also wants to shed at an appropriate height that it wont clash with suspension members and break down. Equally the vortex strength wants to be insensitive to variations in ride height and rake as the car corners/accelerates/brakes. Towards the middle of the wing load wants to be maximized so the car has front grip, so you see the greatest camber and incidence here. Then towards the tip they want less load to reduce induced drag from the wing tip, so there is little camber or incidence. The tip is also raised from the bottom of the wing to further reduce vertical load.
Once that skeleton is defined a number of 3-d splines will join the section profiles together, at least 4 splines per wing element. This defines the "normals" of the wing ends, so how acutely they blend and the angle (both planform and front projected) at which they terminate - there are specific rules about the angle the wing can form with the endplate region. Finally the wing can simply be lofted from all the sections and guide curves created.
There is not any dihedral in an F1 wing, similarly the sweep is primarily an aesthetic thing, but there is a lot of twist and specific local ground clearance across the span.
Hope that helps.
ahmedshafie wrote: ↑23 Jan 2021, 04:37
for multi element y250 , does nasa02 at angle 4 will be same angle for different elements ?
Sorry I thought you meant the actual central, single element, section of the wing. The Y250 vortex generating bit of the wing is defined same as above.
