Rear diffuser?

[freebeard]

The Bonnevette in Permalink #2 had a duct wall that started at or before the axle line. It walls off the underbody flow from the wheelwell turbulence.

I think the outer wall of a rear wheel spat is optional for the reason you state.

[Phase]

Originally Posted by freebeard

The Bonnevette in Permalink #2 had a duct wall that started at or before the axle line. It walls off the underbody flow from the wheelwell turbulence.

I think the outer wall of a rear wheel spat is optional for the reason you state.

so pretty much i could taper in the rear wheel spat to a straight diffuser, while blocking in the wheel well section from messing with the underbody, then expand that area out and wider from the inner section of the flat underbody/diffuser. dont know if i would both boat tailing behind the rear wheel wells, or maybe just do a mild boatd tail behind the wheel to slighly guide the edge air at the side ends of the diffuser

[aerohead]

Originally Posted by Phase

so pretty much i could taper in the rear wheel spat to a straight diffuser, while blocking in the wheel well section from messing with the underbody, then expand that area out and wider from the inner section of the flat underbody/diffuser. dont know if i would both boat tailing behind the rear wheel wells, or maybe just do a mild boatd tail behind the wheel to slighly guide the edge air at the side ends of the diffuser

The diffuser defines all the other architecture.
Once the diffuser is defined, it will reflect on the wheel skirt design.
The diffuser can close the gap of the wheel well, up to the inner face of the rear tires.
The wheel fairings would only be behind the wheels.
And these wheel fairings would create fences on the outer extremities of the diffuser.

[Phase]

Originally Posted by aerohead

The diffuser defines all the other architecture.
Once the diffuser is defined, it will reflect on the wheel skirt design.
The diffuser can close the gap of the wheel well, up to the inner face of the rear tires.
The wheel fairings would only be behind the wheels.
And these wheel fairings would create fences on the outer extremities of the diffuser.

Yeahs that’s what I’m going for. Main diffuser air between the wheel wells, and then bring in the trailing edges of the wheel skirts like a mini boat tail that also acts as some fences/strakes. I saw one of the newer Priuses doing something similar actually

[Phase]

Obviously I’d have deeper boat tailing behind the rear wheels to create the fences. It would look like a pinching shape behind the wheels once I have the rear wheel skirts over. Tesla also uses mini rail guards next the inside wheel wells to block off some turbulence and guide the air out to its diffuser

[serialk11r]

I can't find the original Lotus Exige wind tunnel testing page I read a lot of years ago but this is a pdf of another? (or maybe the same one): https://www.reverie.ltd.uk/Downloads...st_Session.pdf

Notice that the extended strakes to seal off the wheels drops drag by a massive amount.

[Phase]

Saw this yesterday. Now that’s a rear diffuser…

[freebeard]

Notice that the extended strakes to seal off the wheels drops drag by a massive amount.

I scanned through there, (), do you have a page or image number? Front or rear wheels?

[kach22i]

Originally Posted by serialk11r

I can't find the original Lotus Exige wind tunnel testing page I read a lot of years ago but this is a pdf of another? (or maybe the same one): https://www.reverie.ltd.uk/Downloads...st_Session.pdf

Notice that the extended strakes to seal off the wheels drops drag by a massive amount.

Nonactive video links in the PDF when I viewed it, would you by any chance know where they are online?

They claim large differences in drag, I'm just not as impressed as the authors I guess.

[aerohead]

Originally Posted by freebeard

I scanned through there, (), do you have a page or image number? Front or rear wheels?

It's @ #9, at te bottom of the first 'RESULTS' table.
Adding the outboard diffuser vanes dropped drag, from Cd 0.555, to Cd 0.496, a delta- 0.059, 59-counts, a 10.63% reduction.
Polishing a turd.