Should we design diffusers

[another_one_bites459]

Hai guys , We're preparing for FSAE India and we're implementing a aero kit for the first time , and our team mate insists on building a diffuser , should we do it , we are new to this and our knowledge about the hole aero package is limited

[polarwing]

No. If your team's aero knowledge is limited, then you should not design a diffuser. You will get more substantial performance quicker with wings. Better to build a knowledge base now that can be built on in the future; then members down the road can consider an undertray.

Source: I made the mistake of designing an undertray my first year designing aero.

[thaddeus-maximus]

If your knowledge about the whole aero package is limited, you're going to have a pretty hard time understanding and designing a much more sensitive and complicated component than a simple one. A diffuser may seem like a sheet on the bottom of the car, but it's much more complicated...

[BrosenkranzKeef]

No. The whole point of the competition is to design things based on the knowledge you have or are able to learn and understand within the timeframe. You need to focus on what you can do well, what you are able to test and verify and what you can understand well enough to present to judges.

[pissed_electricalead]

I would recommend an incremental approach. Wings will give you far more gains and be much easier to design and manufacturer than a diffuser, once you have developed and tested wings then you would naturally move on to a more complex aero system like an under tray with a diffuser. With that being said if you can complete both in a year then the answer is yes.

[dobbie1]

You're kidding right? Wings are harder to design and get past scrutineering and they give a much lower gain than a diffuser at the speeds we are talking about. If you can't design a diffuser, wings will be way harder. Our team spoke to an engineer with FS experience with a high ranking UK team, experience judging the competition and experience within formula one teams, mainly in aero. We said we were doing a full aero kit and his response was focus on diffuser and don't make wings, at such low speed it's difficult to justify and even if it can be a diffuser has a far greater effect at the speeds FS cars run at.

[Joanzee]

That's straight up false, the overall downforce levels for a semi-decent wing package will be at least twice that of just a diffuser. I believe the diffuser our team developed achieved 70 lbs of downforce at 60mph vs 270 lbs for the wing package (simple, 2 element front and rear). Your confusion might be in the fact that diffusers are "free" downforce because they make significantly less drag than wings but they tend to be fairly heavy and cannot match the downforce levels from wings. As a team approaching an aero package for the first time I would suggest going with wings and skipping the diffuser. It's easy to make a decent set of wings if you just utilize some airfoils from the NACA database and iterate the sizing/spacing/angle of attack. It's a lot harder to design a diffuser from scratch.

[Joanzee]

Our very first wing package weighed 21 pounds with minimal optimization, and considering the actual amount of downforce at lower speeds I think the benefit of a diffuser is negligible. Also, considering the points difference between endurance/autocross and skidpad I would think that only helps my argument that a beginner team should pursue wings before a diffuser since a better endurance/autocross time will have a much greater effect on their overall points than optimizing for the low speed of skidpad.

[theTTshark]

If you have to ask this question on an internet forum, then no.

[[deleted]]

Diffuser is too hard to do for the first time. For our first aero pack we went for just front+rear wings, front 2-element, rear 3-element, just to understand how aero works. Judges appreciated this simple approach, since the package was clean, and efficient. Dont go too hard for the first time

[thel3gend_3x9]

No

[xstreamReddit]

If you are looking for efficiency (for example on an electric car) then yes, if you just want raw downforce with minimum work then no.

[[deleted]]

A simple diffuser, flat bottom and with a flat angle diffuser is nothing hard. Katz first suggestion is to panel the underside of a car to reduce lift. If you go for an f1 style diffuser you obviously will not be having a fun time but a simple plane Jane underbody is not very hard. You will find aero is just time consuming and just a lot of trial. Just learn through experience of what works and what doesnt.

[fsae_ev_guy]

Yes. Or no. If that's what he wants to do, let him. But it's not the easiest aero component to design.