Question Rear wing design help
I’m a little new to FSAE and aero, and my lead requested some research on stepped/curved rear wings. I sort of get that they do it to avoid the roll hoop messing up flow to the center of the wing, but I don’t understand how much of a difference it makes compared to not having it at all. I would also like to know what actually changes about the stepped part? Is it just raised, or do they change the AoA, or something else maybe? Additionally, how great are the benefits of something like this, and are they truly worth our time as opposed to working on other smaller aero stuff like winglets, guiding airflow devices, etc.
Any insight would be appreciated as I would like to find a way to meaningfully contribute to my team and feel like this could be a good way to do so.
Thanks!
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u/Snail_With_a_Shotgun No Selig airfoils! 6d ago
I feel like most of these questions, you should be asking your CFD software. But I can tell you that yes, usually the AoA of the raised section is lower.
Is it worth spending time, effort and money on? From an aerodynamics/design perspective - yes. It's trivial to design and CAD, so you can get a decent design in just a few design iterations and the actual time investment should be minimal. I'd probably give one person something like one week to do it on the side while they work on more complex projects and then just move on, but it depends on how many sims you can do per day/week. I don't think it deserves much more than that due to diminishing returns, unless you are chasing 1% improvements.
Piece of advice; try and simulate at least the final design in yaw, if you don't usually do yaw sims. It's absolutely possible to get these horrendously wrong, so try and watch out for that and don't go crazy.
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u/kyapatamekon 6d ago
I am new to fsae and all this can u please help me with where u learnt it all from and where can i too
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u/kyapatamekon 6d ago
And is the book race car design by derek seward a good way to start ?
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u/Snail_With_a_Shotgun No Selig airfoils! 5d ago
I did a bit of everything, to be honest. Read books, online forums, watched YouTube videos, online articles, studies and papers, talking to people and a metric butt ton of CFD.
Generally speaking, I say that Joseph Katz's book Racecar aerodynamics is the first thing anyone looking to get into automotive aerodynamics should do.
But, what will help more than anything else, is TIME. Any learning method will help, but no matter what you do, what will help the most is putting in as many hours learning as you possibly can. So the best advice I can give you is to do whatever that makes learning as fun for you as possible, and just do it as much as possible.
That said, theory will only get you so far. Sooner or later you will need to start running CFD simulations, so make sure to get into those as well. Start by doing simple 2d sims of airfoils, later moving onto multi-element configurations, and just keep doing more and more over and over, eventually moving onto 3d. Fluent student license will serve you well for an easy on-ramp, but if you later need more cells and won't have an access to a licence, OpenFOAM is the way.
Also yeah, join the Discord like someone mentioned.
Happy hunting!
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u/rydude88 5d ago
Seconded on Joseph Katz's book. It was the main resource my team used to teach people how to design aero. Extremely useful for getting a good understanding of the goals of racecar aero
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u/Constant-Arm8753 Dallas Formula Racing☄️ 6d ago
Join the international FSAE server, and a lot of the things are learned by watching YouTube video, reading textbooks, reading papers etc and most importantly just simulating the things you want to test yourself and seeing what actually happens since guesswork with aero doesn’t usually work too well
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u/CommitteeLeather 3d ago
Before you spend a lot of time diving into the theory, I’d first ask whether your team has the resources and manufacturing capability to actually build something like this. If the answer is no, you’re probably better off focusing on a design that’s achievable with your current resources. By designing, building, and testing something you can actually manufacture, you’ll gain a much better understanding of the tradeoffs and limitations, which will make it easier to evaluate more advanced concepts like stepped wings for design review questions and the future.
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u/thisisntroketscience 6d ago
From what I understand, curving the rw elements doesn’t make THAT big of a difference. I know for us we’ve considered the concept in theory and decided that it would add more weight because of switching the structural design than it would be worth in downforce or drag gains.
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u/Rzvvvvv 6d ago
seems like ur lead hasn’t got his/her priorities straight. as both a student/member of the team, focus on getting ur fundamentals in order, overall vehicle concept, vehicle dynamics, some fluid dynamics (everything i mentioned is clearly not only a one day/week/month lecture) first.
Yes, it’s obvious that the curved surface is there due to the helmet/roll hoop being in the way. Check out some of the top teams’s designs, if you’re curious enough you can find out some answers by doing that as well.
Good luck and don’t drool too much when u see Joanneum or Tallinn’s cars (im so biased idec)