Overcut sidepods?

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shelly
shelly
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Re: Overcut sidepods?

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Exactly. No undercut also for rb6, 7 and 8. This is a constant feature on this line of cars
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bhall
bhall
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Joined: 28 Feb 2006, 21:26

Re: Overcut sidepods?

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We've seen "overcut" sidepods before.

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Image

shelly
shelly
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Joined: 05 May 2009, 12:18

Re: Overcut sidepods?

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Yes but in the 70s they did not have proper tools to evaluate aero, The rb5-8 sidepod width is something much more interesting in my opinion. No othe big team seem to follow, except lotus.
Usually you would want the narrowest section of sidepods to decrease energy loss: we have seen mclaren and ferrari this year for example, exposing a large parte of black floor even at the widest sidepod section. Rbr has always treated this zone differently, in a way that's opposite to what otheres try to do. Why?
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hollus
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Joined: 29 Mar 2009, 01:21
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Re: Overcut sidepods?

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My guess is that spillover from that zone will extract some air from below the floor, or at least counter the influx. A bit like Lotus' FEE as a lot of air is being forced outwards. It would explain part of the drag too and partly why they often got away with more rake than everyone else. But then why not make the sidepods start to waist back even closer to the floor's edge?
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shelly
shelly
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Re: Overcut sidepods?

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I am not sure it is related to spillover; I think instead that the choice is dictated by three concurrent aims:
-create a low pressure zone (corresponding to the point when the flow turns from ouward toi inward on the sidepod) in communication with the floor -ie immediately above it
-avoid that low pressure could act on the upper pointing surface of an exposed floor by using all width
-producing a shorter even if wider sidepod, that (in rbr view?) could be more useful than a narrower but longer packaging in potimising flow over the top downstream part of the floor
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timbo
timbo
111
Joined: 22 Oct 2007, 10:14

Re: Overcut sidepods?

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n smikle wrote:You mean remove the undercut at the rear of the side-pod or the undercut at the radiator inlet?
The RB5 had no undercut at the back.
I say diminish undercut at the radiator inlet.

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turbof1
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Re: Overcut sidepods?

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shelly wrote:Yes but in the 70s they did not have proper tools to evaluate aero, The rb5-8 sidepod width is something much more interesting in my opinion. No othe big team seem to follow, except lotus.
Usually you would want the narrowest section of sidepods to decrease energy loss: we have seen mclaren and ferrari this year for example, exposing a large parte of black floor even at the widest sidepod section. Rbr has always treated this zone differently, in a way that's opposite to what otheres try to do. Why?
no, the cars had a complete different philosophy. They worked as one giant wing which aided the ground effect. Undercut sidepods would not have aided that model.
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Just_a_fan
Just_a_fan
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Joined: 31 Jan 2010, 20:37

Re: Overcut sidepods?

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shelly wrote:I am not sure it is related to spillover; I think instead that the choice is dictated by three concurrent aims:
-create a low pressure zone (corresponding to the point when the flow turns from ouward toi inward on the sidepod) in communication with the floor -ie immediately above it
-avoid that low pressure could act on the upper pointing surface of an exposed floor by using all width
-producing a shorter even if wider sidepod, that (in rbr view?) could be more useful than a narrower but longer packaging in potimising flow over the top downstream part of the floor
I would say that the RB sidepod design is packaging-driven and that the downstream benefits in terms of diffuser effectiveness are larger than any losses that the undercut deisngs try to minimise. If you see what I mean. In effect, RB's philosophy at the rear couple to their packaging demands drives them to form the sidepod as they have. Form follows remote function, if you will.
If you are more fortunate than others, build a larger table not a taller fence.

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FW17
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Joined: 06 Jan 2010, 10:56

Re: Overcut sidepods?

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Image
Image

shelly
shelly
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Joined: 05 May 2009, 12:18

Re: Overcut sidepods?

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turbof1 wrote:
shelly wrote:Yes but in the 70s they did not have proper tools to evaluate aero, The rb5-8 sidepod width is something much more interesting in my opinion. No othe big team seem to follow, except lotus.
Usually you would want the narrowest section of sidepods to decrease energy loss: we have seen mclaren and ferrari this year for example, exposing a large parte of black floor even at the widest sidepod section. Rbr has always treated this zone differently, in a way that's opposite to what otheres try to do. Why?
no, the cars had a complete different philosophy. They worked as one giant wing which aided the ground effect. Undercut sidepods would not have aided that model.
At the tiem of the picture the only wing car was lotus. Anyway, they did not have the tools to evaluate the effects of undercut. Probabaly, but I am not as sure, they could not builddouble curvature surface bodywork until early 90s
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Neno
Neno
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Joined: 31 May 2010, 01:41

Re: Overcut sidepods?

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WilliamsF1 wrote:Image
Image
this lambo looks great, i never saw similar shape of sidepods before. the car looks like piece of art :shock: :shock:

gixxer_drew
gixxer_drew
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Joined: 31 Jul 2010, 18:17
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Re: Overcut sidepods?

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shelly wrote:I am not sure it is related to spillover; I think instead that the choice is dictated by three concurrent aims:
-create a low pressure zone (corresponding to the point when the flow turns from ouward toi inward on the sidepod) in communication with the floor -ie immediately above it
-avoid that low pressure could act on the upper pointing surface of an exposed floor by using all width
-producing a shorter even if wider sidepod, that (in rbr view?) could be more useful than a narrower but longer packaging in potimising flow over the top downstream part of the floor

Sorry Im bringing this up from the dead. I hope nobody minds. To be honest some of the terms used in this thread are different than I am used to so I may be misunderstanding something so please correct me if I am.

I wondered when i saw the difference in their side pod shape and their increased rake.... Any time you improve the stuff in the front of the car with a higher downforce strategy you almost invariably rob the underbody of "clean" air and so the diffuser suffers. On a higher downforce car the diffuser will get a larger amount of its feed air from around the side of the car and so on a car which is more diffuser dependent you are often trying to recover those losses.

Any given design of diffuser or tunnel or whatever if you imagine it in isolation, it will improve its performance by either increasing the pressure before you enter the diffusion section, decreasing the pressure at the back of it (same for increasing the quality and quantity of the feed air). So if you have clean air coming in from around the sidepod and you let it spill around to the underbody (rather than out the back to fill the wake) a larger amount of ground clearance at the back can help that. The increased rake could possibly be to help with diffuser "supply side" if its worth the trade off. Rake will also pickup some downforce in the forward areas of the flat floor by nature of the angle of attack. So you pick up downforce on both front and rear by improving the supply into the diffuser and giving angle to the floor. People seem to think its always about sealing the underbody off but it all depends.

I think to be honest.... their design is all working in harmony and is simply a higher downforce design than others. Others will try that side pod shape but it may not test out beneficial because they aren't using all the other pieces of the puzzle.

Now whether or not this is a more or less *efficient* approach I could not say for sure.. but is conceivable to me that in terms of L/D it could potentially be a better tradeoff, even if it was looking at a higher raw drag coefficient. That is just venturing a guess though and perhaps not really relevant either. The real question to me is not the efficiency but what follows out to a quicker lap time and what wont get you passed on the straight. To me though DRS changed that.... Having a gap before the straight away gains a greater value, you need to avoid the car behind getting within DRS range. If you are behind them and can catch before the straight you will have a higher top speed no matter what. In my uninformed overly-simplistic analysis I would say go for a high downforce strategy start with a more agressive front wing, follow through to less side pod undercut and more rake. Could help with tire management as well.

MadMatt
MadMatt
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Joined: 08 Jan 2011, 16:04

Re: Overcut sidepods?

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WilliamsF1 wrote:Image
Image
Would have been quite scary to drive that if a Sato-Heidfeld (A1-Ring 2002) would have happened !

shelly
shelly
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Joined: 05 May 2009, 12:18

Re: Overcut sidepods?

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Image
From this view angle it seems that the new sauber has overcut (still having undercut at the start of the sidepod tough)
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shelly
shelly
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Joined: 05 May 2009, 12:18

Re: Overcut sidepods?

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And on the new redbull again the sidepod is the widest of all - extends to the fllor side limit
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