Rear diffuser?

[Phase]

Originally Posted by aerohead

Technically, this 'porosity' would take away from the diffuser's performance.
It needs to be as air-tight as can be made.
Maybe, add material to the bottom of the rear fascia, down until it meets the 'flat' angled diffuser.
I know you're not made of money. Some sort of heat-proof material near the muffler. freebeard's volcanic basaltic spun glass fiber would be wicked cool.
Scrap aluminum. Sheetmetal cut from the discarded door of an abandoned, deceased refrigerator. I've used the sheet metal from worn out gas water heaters.

https://youtu.be/VtyF6ZU-9hw

did you see the video of the underside? its pretty much going to be about an inch away from the muffler, and ill use heat shield aluminum tape on the abs plastic edge thats facing the muffler and exhaust.

it wont be perfectly flat, but from what ive seen in many cfd tests, is that a diffuser still adds benefits even without a perfect flat floor, its just maybe 70 percent of a possible 100 percent improvement. its still a plus, but not the best possible improvement.

right now im just focused on the diffuser, later on my plans are to smooth out the whole under body. theres still a '' canyon'' under the middle of the car where the cat converter is. so i also need to fab up a cat shield and cover for that whole area. ill be doing a super smooth underbody floor cover when i have access to a jack or car lift again

[IRONICK]

In your film it can be seen that you did not "treat" the rear axle area at all.

For Ioniq 2022 Hyundai solved also the rear part.

You will implement the air diffuser alounst for nothing, if you do not solve how the air gets there.

[IRONICK]

Originally Posted by aerohead

If you'll do additional heat-shielding, exhaust wrap, or both, heat shouldn't be an issue. ICBM missile silos use nothing but concentric rings of sheet metal shells with dead air spaces in between to insulate them.
Kenny Lyon's BMW exhaust system was completely-wrapped on his Cd 0.11 streamliner motorcycle. And he was 'inside' the body at all times, with the exhaust!

Don't need any insulation, an aluminum plate with one air inlet and many exits along the central tunnel.

[aerohead]

Presently, the Chinese, GAC ENO. 146 is the industry low-drag benchmark, @ Cd 0.146.
The ENO's diffuser constitutes nearly the entire underbody of the car.
And it never exceeds a 4-degree upswept angle.
http://https://autodesignmagazine.co...d-by-the-wind/
Looks like the link failed. Sorry!

[Phase]

Originally Posted by IRONICK

In your film it can be seen that you did not "treat" the rear axle area at all.

For Ioniq 2022 Hyundai solved also the rear part.

You will implement the air diffuser alounst for nothing, if you do not solve how the air gets there.

That’s a totally different EV car that you’re mentioning. Might as well compare to a Tesla. The Ioniq 5 and Ioniq hybrid aren’t even the same shape…

[IRONICK]

Do it in your way. And you will convince yourself that it doesn't help you as you think.

[IRONICK]

Originally Posted by aerohead

Presently, the Chinese, GAC ENO. 146 is the industry low-drag benchmark, @ Cd 0.146.
The ENO's diffuser constitutes nearly the entire underbody of the car.
And it never exceeds a 4-degree upswept angle.
http://https://autodesignmagazine.co...d-by-the-wind/
Looks like the link failed. Sorry!

Because they also let the air in...

https://uploads.ifdesign.de/entry_ex...try_medium.jpg

https://uploads.ifdesign.de/award_im..._146_1_rev.jpg

https://uploads.ifdesign.de/award_im..._146_2_rev.jpg

https://uploads.ifdesign.de/entry_ex...try_medium.jpg

[aerohead]

I can see a NACA submerged inlet on the near side under nose image. If it's 'twins', I don't yet know where they exhaust to.
And voids above the two outer 'slow' diffuser sections. I've no idea what's going on in those voids.
The center of the diffuser is radical. That cost me me almost 5-mph at Bonneville.
I haven't seen a top-speed mentioned for the car.
If it's a 'high performance' sedan, then there will be drag concessions to high-speed directional stability.
The GAC's lower body begins final plan-view boat-tailing where the small of the back for the rear seat is located.
The greenhouse begins plan-view boat-tailing at the driver's hips.
The base pressure of the wake would be relatively high, perhaps exceeding the pressure at the beginning of the rear wheel-houses.
Without a Cp profile along the top, sides, and bottom of the car, it's hard to know where local flow would favor direction.
One Chinese auto journalist has mentioned that aerodynamics is not something of interest to Chinese consumers, and the GAC will never be manufactured; so the prospect of any 'road tests' of the 146 is just a pipe dream.

[IRONICK]

Since the front part of the car has nothing open for cooling, this is probably its role. It is obvious that the car is not made to go on the streets.

[aerohead]

Originally Posted by IRONICK

Since the front part of the car has nothing open for cooling, this is probably its role. It is obvious that the car is not made to go on the streets.

Perhaps, with adaptive suspension, on a well-maintained interstate highway, where there's no need of SAE approach, breakover, departure angles, or ground clearance, it would be just fine.
I'd like to find out.