Scuderia Ferrari SF71H

A place to discuss the characteristics of the cars in Formula One, both current as well as historical. Laptimes, driver worshipping and team chatter do not belong here.
User avatar
Mr.G
34
Joined: 10 Feb 2010, 22:52
Location: Slovakia

Re: Scuderia Ferrari SF71H

Post

mounted in front
mounted in back

Here is good visible, that the mirrors are mounted symmetrical...

Also it look like the top side is enlarged only on the inner side (closer to the tub) and not on the outer side (so the enlarged section is "triangular". Or the second option may be that the mirrors inside are angled for the driver, so it appears that it's elongated on the inner side.

EDIT: I've just realized that they don't have the IR cameras on the mirrors for the front tyres. They will be probably incorporated to the final version of the mirrors (hopefully we will see them in 2nd test) or they will be placed in different position.
Art without engineering is dreaming. Engineering without art is calculating. Steven K. Roberts

Mat-tes
Mat-tes
30
Joined: 20 Feb 2016, 15:17

Re: Scuderia Ferrari SF71H

Post

Loads of interesting theories here, and since I have zero technical background in the matter I'm not going to comment on technical things too much.
I just looked around for pictures of the mirror side (back) of the mirror to try and see if anything is visible.
I couldn't find a dead on picture nor could I find anything in HD, but for now it seems that the inner element of the mirror is just floating in the middle of the outer shell, suspended by the central small pylon. That we all figured out on the front facing pictures, but from the back it looks like at least for the bottom edge the air is just passing through, and although there is a possibility that the other edges of the mirror might be connected to a duct or something because not yet visible on picture, I would assume it's just letting air go through on all 4 edges.
This might just be an always ON smaller version of the McLaren f-duct, as someone pointed earlier the slit on the McLaren's rear wing was really small yet the effect were quite significant. Unlike the s-duct, you never need anything from the mirror as they are just in the way, so why not try to have a system that always reduces the drag at all time, at slow and high speed, plus try to deflect air in more useful area of the car. This could concur that this device might be mainly oriented at drag reduction. On the rest of the car significant effort have been put in drag reduction, so why not on the mirrors as well.

Image

The top left picture is the clearest one I could find, and I just highlighted the gap and central pylon inside the red circle (bottom left picture).

If the air was to be ducted somewhere else, why go through the hassle of taking it from the mirror and not a regular inlet somewhere on the main body?

It would be surprising that before the end of the test or during the season we don't get some nice pictures and maybe some useful information as to why these mirrors are shaped this way. Maybe other teams will jump on board as well.

User avatar
turbof1
Moderator
Joined: 19 Jul 2012, 21:36
Location: MountDoom CFD Matrix

Re: Scuderia Ferrari SF71H

Post

manchild wrote:
04 Mar 2018, 16:53
@turbof1

I'm not an aerodynamicist, athough I have formal automotive education.

One of the things life teached me is that you can sometimes learn things even from the illiterate people, while sometimes you can't learn a thing from those with university degree.

Analytical thinking is something one is born with as a natural gift, but there is no such thing as educational method that makes thinkers out of ungifted.

I'm not denying knowledge of the professionals, but some of them are extremely narrow-minded, and strictly limited to what they've been thought, without the ability to analyze new things and think out of the box. Not to mention lack of creativity.

So, I like to learn new stuff from whomever, but I also have no respect to authority if they can't backup their claims.

Some things are so obvuious, but vanity and the ego prevent them to at least publically admit that they were wrong or that someone without a degree has come up with something they weren't able.

An example of what I'm talking about - Absolute majority of electro engineers wouldn't be able to make same gadgets Tesla has made 120 years ago if they would be given only tools and materials he had at disposal. On the other hand, there are self-thought people with just elementary or secondary education who are simply able to do those things.

As long there is logic instread of authoritative or biased imposition, I'm ready to listen and accept.
For the record, I'm not calling anybody illiterate. Let's not blow that out of proportion.

However, I do believe that a person with an educational AND professional background in aerodynamics, one who actually has the academic education and the experience to boot, should be always be taken serious. It is fine if you disagree, but do accept there is more credibility behind that person's word because it is his field. I'm stating this as a person who has absolutely no experience -academic and/or professional- in aerodynamics. Everything I learned about aerodynamics I have learned through this website. And guess what? I was wrong in the past too! I also thought I simply had to trust my analytical thinking and my gut feeling. I got proven wrong, by someone who had the background which I do not have.

Again, I'm not telling you to willy nilly accept things that are put in front of you. But if you think the person is wrong and you want to publicly adress it, then you will have to disprove his or her arguments. I have found that impossible myself, and I tried my darnest :lol: . Let's be real here, I think this more than a serious attempt by someone to back their claims:
Vanja #66 wrote:
02 Mar 2018, 00:44
Mirror brackets, in my opinion, most likely guide the air towards that top inlet. I've written already a bit on mirrors here, but I'll gladly add to it.

http://i64.tinypic.com/33a4adi.jpg

This is the first mirror bracket design in 2017, and as far as I remember, only used in winter testing. Throughout the season, Ferrari used the same bracket design as current one. Design on picture is lifting the mirrors as high up as possible and is using additional flap to get some of the air flowing on the inner side of mirror bracket (closer to the driver) to the top inlet. Current design is doing that as well, but with a curved design they are using more air for less drag (slots induce drag, that flap in launch spec design caused a vortex which induced drag as well) and have lowered the mirrors for better visibility (look how far down the list their primary function lies).

As for current mirror fairing design, it's there to reduce drag. If they wanted to move the air from the mirror to the inlet with this design, they'd lower the mirrors even more. Mirror position (in terms of height) hasn't changed from last year's final design. Last year mirrors weren't flow-trough, ergo - they were a problem, they caused turbulence (as ever) and they needed to be as high as possible not to obstruct air flow, but as low as possible not to hinder driver visibility even further.

To end this with something basic - you don't want turbulent air in your radiator intake and even if you did, you can't make it go to the high pressure zone of top inlet.

Some things are simple, some are not and not everything in F1 is complicated.
I mean what he says is true. If they goal is to redirect flow to the pods, why not just lower the mirror? Or change the profile of the mirror into a more suitable shape? He also hits the nail on the heat as you don't want to use turbulent airflow for cooling, which is exactly what's coming off the mirrors. Cooling works best with undisturbed flow. That's not a new concept. I can remember people mentioning this as far back as 10 years ago.

That's everything I have to say about that. Let's get the show back on the road.
#AeroFrodo

User avatar
Vanja #66
1572
Joined: 19 Mar 2012, 16:38

Re: Scuderia Ferrari SF71H

Post

manchild wrote:
04 Mar 2018, 15:03
Besides the influence of shape of the branches on overall aero, the variation also considers that shorter has the ability of greater flow, so they'd choke at higher speed than with the longer ones.
Could you elaborate this? Interesting idea. How can a channel or a duct get choked in an open system exactly?
AeroGimli.x

And they call it a stall. A STALL!

#DwarvesAreNaturalSprinters
#BlessYouLaddie

manchild
manchild
12
Joined: 03 Jun 2005, 10:54

Re: Scuderia Ferrari SF71H

Post

Vanja #66 wrote:
04 Mar 2018, 19:49
manchild wrote:
04 Mar 2018, 15:03
Besides the influence of shape of the branches on overall aero, the variation also considers that shorter has the ability of greater flow, so they'd choke at higher speed than with the longer ones.
Could you elaborate this? Interesting idea. How can a channel or a duct get choked in an open system exactly?
Choking occurs when the speed/amount of air surpass the capacity of duct. The pressure increases to the point when air begins turbulently spilling over the duct entrance and because of that the duct can't pass it trough.
Longer duct of the same diameter as the shorter one, has lower capacity and will choke sooner, because it takes more time for the identical amount of air to pass trough it.
If you've ever dived using snorkel, you've likely noticed that it is easier to breathe trough shorter snorkel than trough longer one. That's the principle.
Last edited by manchild on 04 Mar 2018, 20:37, edited 1 time in total.

Downforce
Downforce
2
Joined: 10 Feb 2006, 01:17
Location: Belgrade, Serbia

Re: Scuderia Ferrari SF71H

Post

Well, I think that their function is somewhat combined...they are decreasing drag and increasing flow to the radiators...

Image
https://imgur.com/mwaISiY

Small gaps are used in some form of a nozzles. They are increasing velocity of the flow with the speed Vn.That speed is larger than the incoming speed of the free air VF, so they are using this flow to decrease speed of the incoming free air an to increase its pressure just above the sidepod inlet. The aren't using air behind and below the rear view mirror (turbulent one) - they are using clean air in front of it.Upper part of the mirror is also diverging air in the same manner. Angle of the this "nozzle" flow is tuned to follow contour of the sidepods, and in same time decrease drag of the mirrors.

Mirror stand is also used to divert free air into this zone above the sidepod inlet, and downwards towards the floor, following the upper surface of the sidepods.

Mounting on the chassis is deliberately made like that so that they could finely tune this.

mmred
mmred
-3
Joined: 25 Apr 2017, 14:19

Re: Scuderia Ferrari SF71H

Post

manchild wrote:
04 Mar 2018, 20:16
Vanja #66 wrote:
04 Mar 2018, 19:49
manchild wrote:
04 Mar 2018, 15:03
Besides the influence of shape of the branches on overall aero, the variation also considers that shorter has the ability of greater flow, so they'd choke at higher speed than with the longer ones.
Could you elaborate this? Interesting idea. How can a channel or a duct get choked in an open system exactly?
Choking occurs when the speed/amount of air surpase the capacity of duct. The pressure increases to the point when air begins turbulently spilling over the duct entrance and because of that the duct can't pass it trough.
Longer duct of the same diameter as the shorter one, has lower capacity and will choke sooner, because it takes more time for the identical amount of air to pass trough it.
If you've ever dived using snorkel, you've likely noticed that it is easier to breathe trough shorter snorkel than trough longer one. That's the principle.
actually the window inner shel is exactly designed that way to prevent it from stop functioning at high speeds
choking happens because of the natural enrichment of the boundary layer with increase of air flow due to turbulent flux prevailing
so in normal ducts the layer reaches a size in wich opposite walls create a unique zone of wall slowing down and choking and eventually reaching backwards the mouth of the duct and creating a deviation from there

the ferrari mirror internal edge is not shaped like a normal profile ( that would reduce its drag at lower speeds ) but it has a thin edge to work better at higher speeds by creatin pressuriezed zones that keep the boundary layer attached


FYI

mmred
mmred
-3
Joined: 25 Apr 2017, 14:19

Re: Scuderia Ferrari SF71H

Post

Downforce wrote:
04 Mar 2018, 20:26
Well, I think that their function is somewhat combined...they are decreasing drag and increasing flow to the radiators...

https://imgur.com/mwaISiY
https://imgur.com/mwaISiY

Small gaps are used in some form of a nozzles. They are increasing velocity of the flow with the speed Vn.That speed is larger than the incoming speed of the free air VF, so they are using this flow to decrease speed of the incoming free air an to increase its pressure just above the sidepod inlet. The aren't using air behind and below the rear view mirror (turbulent one) - they are using clean air in front of it.Upper part of the mirror is also diverging air in the same manner. Angle of the this "nozzle" flow is tuned to follow contour of the sidepods, and in same time decrease drag of the mirrors.

Mirror stand is also used to divert free air into this zone above the sidepod inlet, and downwards towards the floor, following the upper surface of the sidepods.

Mounting on the chassis is deliberately made like that so that they could finely tune this.
there s just a problem with that drawing
the mirror section is not pointed downward like that ( it would create too much drag and a mirror is to thin tot act efficiently as a flux deviator, it would basically only create drag)

and the downward flux is overestimated even for that section

for sure it doesnt point the flux upward
for sure the morror ( also last year one ) interacts with the sidepod
but the internal is not at all designed like that nor it can deflect the flux down like that ( that result isnt probably even reached by the wings mounted at the side of the cockpit and those have an adequate winglenght exactly to reach that result

manchild
manchild
12
Joined: 03 Jun 2005, 10:54

Re: Scuderia Ferrari SF71H

Post

With just a tiny space under or even all around the mirror plate but without ducting, it would choke on like 50-100kph, and the dust, rubber and rain would devastate it. With ducting it would occur on much higher speeds.
Someone with CFD could easily test it.
I don't have any.
I'm a visual mathematician :mrgreen:

mmred
mmred
-3
Joined: 25 Apr 2017, 14:19

Re: Scuderia Ferrari SF71H

Post

manchild wrote:
04 Mar 2018, 21:16
With just a tiny space under or even all around the mirror plate but without ducting, it would choke on like 50-100kph, and the dust, rubber and rain would devastate it. With ducting it would occur on much higher speeds.
Someone with CFD could easily test it.
I don't have any.
I'm a visual mathematician :mrgreen:
deviators or front wings complex tunnels usually dont choke
ask yourself why
Last edited by Steven on 04 Mar 2018, 23:08, edited 1 time in total.
Reason: Don't make it personal

manchild
manchild
12
Joined: 03 Jun 2005, 10:54

Re: Scuderia Ferrari SF71H

Post

mmred wrote:
04 Mar 2018, 21:30
manchild wrote:
04 Mar 2018, 21:16
With just a tiny space under or even all around the mirror plate but without ducting, it would choke on like 50-100kph, and the dust, rubber and rain would devastate it. With ducting it would occur on much higher speeds.
Someone with CFD could easily test it.
I don't have any.
I'm a visual mathematician :mrgreen:
deviators or front wings complex tunnels usually dont choke
ask yourself why
there s a reason why you are a mathematcian and not a cfd master
Of course they don't choke, they are not within a box with huge inlet and tiny outlet.
Last edited by Steven on 04 Mar 2018, 23:08, edited 1 time in total.
Reason: Removed personal comments

George-Jung
George-Jung
18
Joined: 29 Apr 2014, 15:39

Re: Scuderia Ferrari SF71H

Post

If these mirrors are designed to reduce drag- than automatically it will have a positive effect on the top sidepod inlet?

So win-win?

User avatar
Vanja #66
1572
Joined: 19 Mar 2012, 16:38

Re: Scuderia Ferrari SF71H

Post

manchild wrote:
04 Mar 2018, 20:16
Choking occurs when the speed/amount of air surpass the capacity of duct. The pressure increases to the point when air begins turbulently spilling over the duct entrance and because of that the duct can't pass it trough.
Longer duct of the same diameter as the shorter one, has lower capacity and will choke sooner, because it takes more time for the identical amount of air to pass trough it.
If you've ever dived using snorkel, you've likely noticed that it is easier to breathe trough shorter snorkel than trough longer one. That's the principle.
What you've described isn't exactly what I've heard and read before about chocking a ducting, very close though. Chocking, as far as I know, occurs when you surpass the maximum mass flow of air in a duct - as you said. Radiator intake is one such example, radiator core has a certain maximal mass flow and it can't be surpassed. As the car speeds up, mass flow trough the inlet would get bigger because of bigger air velocity, so inlet surface effectively shrinks - causing spilling as you mention.

This is because the radiator intake and intake aren't exactly an open system due to very small channels in radiator core and boundary layer expansion having significant effect on effective contraction of each channel in this core. Channels in wing slots between flaps are different, they can't get chocked obviously or the wing would stall and we know this doesn't really happen. In my view, same is in these wing mirrors, you have slots and they are in an open air stream, so they aren't getting chocked.

To be honest, this whole idea about certain geometries (in free stream, i.e. in an open system) getting chocked and stalled at higher speeds is really spread out around this forum and I'm not sure where this originated. :)
AeroGimli.x

And they call it a stall. A STALL!

#DwarvesAreNaturalSprinters
#BlessYouLaddie

manchild
manchild
12
Joined: 03 Jun 2005, 10:54

Re: Scuderia Ferrari SF71H

Post

Try observing mirror fairing as tiny sidepod, and mirror glass with inner fairing as the radiator.
Principle and situation-wise they are identical. Size doesn't matter.
Unless ducted, mirrors would choke at ridiculously low speeds.
Last edited by manchild on 05 Mar 2018, 02:13, edited 1 time in total.

User avatar
ScrewCaptain27
577
Joined: 31 Jan 2017, 01:13
Location: Udine, Italy

Re: Scuderia Ferrari SF71H

Post

Floor blades (F1analisitecnica):
Image
"Stupid people do stupid things. Smart people outsmart each other, then themselves."
- Serj Tankian