Effects of Car in Front of Car Close Behind

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EvilPhil II
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Joined: 08 Feb 2015, 06:21

Effects of Car in Front of Car Close Behind

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Everyone appreciates that when a car is close behind another, that the following car loses down force and can enjoy the benefit of a tow.

I'm wondering if when a following car is close to another car in front if there are any likely effects on the car in front? e.g. can it effect the car in fronts rear wing efficiency by disrupting the airflow off the wing?

CSH17
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Joined: 17 Oct 2016, 20:49

Re: Effects of Car in Front of Car Close Behind

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In NASCAR the effect of the following car is used in pack drafting as the car behind reduces the impact of the low pressure region behind the leading car

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godlameroso
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Re: Effects of Car in Front of Car Close Behind

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You know that's actually a good question, and on the face of it, it does make sense. It's been shown that rear aero affects the front, so why wouldn't a car disrupting rear aero not affect the front end of the leading car? Possibly why Riccardo, and Raikkonen were slow when they were in the middle of the train. And why Verstappen started struggling when he was in a HAAS and Riccardo train.

Maybe pushing and getting close to the lead car affects it's downforce enough that the tires start sliding around a bit more, so it loses some pace and increases tire wear. Although the trailing car suffers a little more, maybe it's still possible to set up an undercut by closely trailing the leading car as much as possible.
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hollus
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Re: Effects of Car in Front of Car Close Behind

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In Nascar, the car behind can be 20 cm behind, or even 0 cm behind.
How often and for how long is it that the car behind is less than 2 car lengths behind in F1?
The effect, is there is any, will be negligible, IMHO.
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marvin78
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Re: Effects of Car in Front of Car Close Behind

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Nascar and F1 are really similar.

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godlameroso
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Re: Effects of Car in Front of Car Close Behind

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Nascar doesn't depend so heavily on aero as F1 does. A NASCAR is essentially a rolling brick by comparison. F1 has flow structures, tiny aero surfaces, and complex interactions from the front wing to the diffuser.
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toraabe
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Joined: 09 Oct 2014, 10:42

Re: Effects of Car in Front of Car Close Behind

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Go back to groundeffect.

bhall II
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Re: Effects of Car in Front of Car Close Behind

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toraabe wrote:
10 Apr 2017, 17:10
Go back to groundeffect.
The vast, overwhelming majority of downforce generated by F1 cars is the result of ground effect. That's not the answer.

Anyway, between two cars running in tandem, the leading car suffers little disturbance. If anything, it might even experience a slight downforce gain...

Image
via SimScale

Just_a_fan
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Joined: 31 Jan 2010, 20:37

Re: Effects of Car in Front of Car Close Behind

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bhall II wrote:
10 Apr 2017, 18:23
toraabe wrote:
10 Apr 2017, 17:10
Go back to groundeffect.
That's not the answer.
It's his only answer. He brings it up in thread after thread.
Anyway, between two cars running in tandem, the leading car suffers little disturbance. If anything, it might even experience a slight downforce gain...

http://i.imgur.com/Cggn1FJ.jpg
via SimScale
It's possible that the leading car gains from the front wing of the trailing car helping to drive the leading car's diffuser. I'd guess it would need to be very close for this to occur but in your image there is a suggestion that it happens.
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EvilPhil II
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Joined: 08 Feb 2015, 06:21

Re: Effects of Car in Front of Car Close Behind

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Would this create understeer for the leading car?

bhall II
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Re: Effects of Car in Front of Car Close Behind

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EvilPhil II wrote:
10 Apr 2017, 23:31
Would this create understeer for the leading car?
In general, increasing the efficiency of the diffuser also tends to increase the efficiency of components upstream.

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godlameroso
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Re: Effects of Car in Front of Car Close Behind

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bhall II wrote:
11 Apr 2017, 01:05
EvilPhil II wrote:
10 Apr 2017, 23:31
Would this create understeer for the leading car?
In general, increasing the efficiency of the diffuser also tends to increase the efficiency of components upstream.
Assuming that 2017 cars have the same wake profile as the previous generation cars, and the leading car's diffuser would work better with a new car in tow.
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toraabe
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Re: Effects of Car in Front of Car Close Behind

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Just_a_fan wrote:
10 Apr 2017, 18:52
bhall II wrote:
10 Apr 2017, 18:23
toraabe wrote:
10 Apr 2017, 17:10
Go back to groundeffect.
That's not the answer.
It's his only answer. He brings it up in thread after thread.


=D>

wuzak
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Re: Effects of Car in Front of Car Close Behind

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godlameroso wrote:
10 Apr 2017, 13:55
And why Verstappen started struggling when he was in a HAAS and Riccardo train.
Verstappen was never in a "Haas and Ricciardo train".

Verstappen was never close enough to get a tow, though he may have felt some effects. But the biggest effect he was having was that his tyres were old and shot.

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RicME85
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Re: Effects of Car in Front of Car Close Behind

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wuzak wrote:
11 Apr 2017, 10:37
godlameroso wrote:
10 Apr 2017, 13:55
And why Verstappen started struggling when he was in a HAAS and Riccardo train.
Verstappen was never in a "Haas and Ricciardo train".

Verstappen was never close enough to get a tow, though he may have felt some effects. But the biggest effect he was having was that his tyres were old and shot.
I think thats the key thing here. He was so far behind the Haas that it must of been tyres that were the issue as Ricciardo was right up behind Max, a lot closer than Max was to the car in front. Now with tyres lasting longer you cant jump in the pits if you are in that situation and claw the places back as other cars slow down due to the age of their tyres in comparison which then creates these 'faux trains'