Renault F1 R.S. 20

[Blackout]

Renault opted for RB-inspired sidepods/engine cover for 2020, like RP during the 2019 season, https://pbs.twimg.com/media/EAU_fpIWsAA ... ame=medium an engine cover that merges the top airflow and the side air flow more upstream of the diffuser...

Let me rephrase: I think they reworked the shape of the undercut, which, seen from above, looks like the upper surface of an airfoil, to displace the lowest pressure area and put it more backwards. And thanks to the overcut, that low pressure area will pull air from the top surface of the sidepod more effectively and direct it in the coke bottle area.



And that's how the "RB" sidepods work... Am I right?
They sweep the widest part of the undercut backward to make the air that accelerates around it suck the top air

That's also the case here (racing point) https://pbs.twimg.com/media/EAU_fpIWsAA ... ame=medium



So the RS.19 undercut shape looked like the ULM upper surface and it's pressure distribution looked thoroughly like this

While the RS.20 undercut shape looks more like that propeller blade upper surface and the lowest pressure area would look more like this


Amarite

[mmred]

Renault opted for RB-inspired sidepods/engine cover for 2020, like RP during the 2019 season, https://pbs.twimg.com/media/EAU_fpIWsAA ... ame=medium an engine cover that merges the top airflow and the side air flow more upstream of the diffuser...

Let me rephrase: I think they reworked the shape of the undercut, which, seen from above, looks like the upper surface of an airfoil, to displace the lowest pressure area and put it more backwards. And thanks to the overcut, that low pressure area will pull air from the top surface of the sidepod more effectively and direct it in the coke bottle area.

https://i.imgur.com/ujLLd0K.jpg

And that's how the "RB" sidepods work... Am I right?
They sweep the widest part of the undercut backward to make the air that accelerates around it suck the top air
https://i.imgur.com/cm5SyfX.jpg
That's also the case here (racing point) https://pbs.twimg.com/media/EAU_fpIWsAA ... ame=medium

https://i.imgur.com/DgI3IEY.jpg

So the RS.19 undercut shape looked like the ULM upper surface and it's pressure distribution looked thoroughly like this https://i.imgur.com/3VgOSoR.png

While the RS.20 undercut shape looks more like that propeller blade upper surface and the lowest pressure area would look more like this
https://i.imgur.com/AEaLggK.png

Amarite

This comparison Is a bit unsupported.
You should compare simmetric airfoils to have a longitudinal section. The 3d effects are Just too manu ti use airfoils

[ringo]

I've had my theory on the sidepods years ago, "ellipse and radii gate", and redbull continue to maintain more or less the same design language; ie develop the least amount of lift across the body (more downforce) with less dependence on wing downforce. Consider the body as a "3D airfoil", and not just a two dimensional airfoil in one plane and it explains why the redbull pods look the way they do.

[mmred]

I've had my theory on the sidepods years ago, "ellipse and radii gate", and redbull continue to maintain more or less the same design language; ie develop the least amount of lift across the body (more downforce) with less dependence on wing downforce. Consider the body as a "3D airfoil", and not just a two dimensional airfoil in one plane and it explains why the redbull pods look the way they do.

Ehm. Vertical airfoils don't generate lift or downforce Only drag, cause they combine each other and cause the Vector Is horizontal....they are like sails

It Is true that some shapes remain but the 3d interaction makes every shapes look fare from an airfoil

[Blackout]

Yes aircraft airfoil arent a very good example... but the upper shape and the pressure distribution/lowest pressure point remain relevant IMO
Here a rough comparison between the RS19 undercut and the RB14 undercut (roughly recreated from this pic https://external-preview.redd.it/ebUuWh ... 3f20dcb34d )
The theory is, RB postpones the widest area of the undercut to put the low pressure area more backward in a place where it can attract the sidepod top air flow, with the help of the overcut that forms a 'ramp'...


Maybe Ringo means this design aims to reduces lift on the upper surface of the sidepod


It's multipurpose IMO because it mixes the top and side airflows to form a more powerful flow for the diffuser.


Interestingly, Renault made another RB inspired move this year and has lowered and directed the rear hot air channels downwards like STR too, probably to channel that mixture closer to the diffuser edges and gurneys, to enhance air extraction

[JordanMugen]

Yes aircraft airfoil arent a very good example... but the upper shape and the pressure distribution/lowest pressure point remain relevant IMO

What a superb post Blackout!

[ringo]

I've had my theory on the sidepods years ago, "ellipse and radii gate", and redbull continue to maintain more or less the same design language; ie develop the least amount of lift across the body (more downforce) with less dependence on wing downforce. Consider the body as a "3D airfoil", and not just a two dimensional airfoil in one plane and it explains why the redbull pods look the way they do.

Ehm. Vertical airfoils don't generate lift or downforce Only drag, cause they combine each other and cause the Vector Is horizontal....they are like sails

It Is true that some shapes remain but the 3d interaction makes every shapes look fare from an airfoil

I was not suggesting that the body is an airfoil, just suggesting to you that it cannot be understood with a 2d airfoil. However you can tell me what a helicopter tail rotor is doing then since it's airfoils are vertical.

[ringo]

Maybe Ringo means this design aims to reduces lift on the upper surface of the sidepod

It's multipurpose IMO because it mixes the top and side airflows to form a more powerful flow for the diffuser.

Correct. If the upper surface is not shaped carefully, there will be regions of low pressure caused from high velocity air moving around the air box area of the engine cover as well as over the flank. A CFD with a cross sectional cut perpendicular to the car would illustrate this well.

[Blackout]

An interesting CFD comparison between the effects of the thumb nose and the thin nose
https://salientedge.com/blog/2018/5/16/ ... ose-part-2

[PlatinumZealot]

As Andy green put it.. With the current regulations it is better for the nose to not to be there at all! So with that philosophy it's aerodynamic signature has to be made as small as possible....

[siskue2005]

As Andy green put it.. With the current regulations it is better for the nose to not to be there at all! So with that philosophy it's aerodynamic signature has to be made as small as possible....

but the regulations has not changed since 2017, why the sudden change to merc philosophy by everyone?
is it due to the 2019 end plate rule change?

[PlatinumZealot]

As Andy green put it.. With the current regulations it is better for the nose to not to be there at all! So with that philosophy it's aerodynamic signature has to be made as small as possible....

but the regulations has not changed since 2017, why the sudden change to merc philosophy by everyone?
is it due to the 2019 end plate rule change?

It is said the crash test is difficult to pass with that style of Nose, which we observed back in 2017 when Mercedes took until Barcelona to implement it on the car. The slim nose causes less disruption to the Y250 Vortices either side of it and that equals more effective floor and barge boards.

[Blackout]

And maybe they had more than enough front DF in 2019, so they didn't mind the loss of DF at the front caused by the thinner 2020 nose? Maybe they have a better DF balance now

[PlatinumZealot]

With the 2014 regulation there was never a lack of front down-force though. It is quite easy to develop it. Rear down-force and balance (aero-stability) were the biggest problems. Notice how front wing development has been very nuanced compared to previous regulations? Teams even "clipped" the wings for 2019.

[Morteza]

Some comparison shots between RS19 and RS20 (via Nicolas Carpentiers)