CFD - 2022 Ferrari F1-75 (sidepod analysis)

[rgimblett]

https://i.ibb.co/2ynvgv5/comp-iso.jpg

https://i.ibb.co/qd9mn28/comp-top.jpg

https://i.ibb.co/HF4K05j/comp-noindent-top.jpg

It's clear right away we have several areas of interest - intake, upper surface and rear surface.

Great work Vanja.... Like some people have already commented there are a number of differences between the reference car and the ferrari sidepod you've modelled. If it's not too much work, would it be possible to re-run the ferrari model exactly the same except the bird bath depression filled in as shown here in red. It would be interesting to see what the depression contributes in isolation.



sorry I'm not good at embedding image links here but you can follow the link to see the markup.

[Vanja #66]

This was already done, the third picture you quoted is exactly that.

[roadie]

Fantastic work thank you. It is fascinating to understand a little more what the philosophies of the different approaches are and the compromises they take account of and result in.

[Vanja #66]

You mean the "smaller airbox, smaller rear wing" that you didn't even model in your CFD analysis? so like others are saying, your analysis is a good reference model, but has enough inaccuracies that using this as anything other than just a general guess is probably not very representative. Stop making this a pissing contest with me since I am not interested - although I am flattered my opinion means so much to you.

You really aren't making a lot of sense, why must those two clear drag differences be modeled and simulated in order to make a claim they generate lower drag? F1 cars were designed long before CFD was invented, you know, not everything about aerodynamics has to be run trough CFD to take away some conclusions.

[rgimblett]

This was already done, the third picture you quoted is exactly that.

Sorry, how did I not see that....

[rgimblett]

This was already done, the third picture you quoted is exactly that.

Sorry, how did I not see that....

Did you publish the CFD plot of the plain top ferrari sidepod?

[Vanja #66]

This was already done, the third picture you quoted is exactly that.

Sorry, how did I not see that....

Did you publish the CFD plot of the plain top ferrari sidepod?

Let me repost this:

These are base model top view and F1-75-like tub-sidepods:



And this is top view of flat F1-75-like tub-sidepods:

[Sevach]

Fantastic work thank you. It is fascinating to understand a little more what the philosophies of the different approaches are and the compromises they take account of and result in.

For a regulation that was suppoused to lead to a bunch of cars looking the same this is much better than promised.
I'm excited to see different concepts and ideas and how they perform, much better than everybody aiming at the same thing but some being slightly more succesfull at it.

[NoDivergence]

You mean the "smaller airbox, smaller rear wing" that you didn't even model in your CFD analysis? so like others are saying, your analysis is a good reference model, but has enough inaccuracies that using this as anything other than just a general guess is probably not very representative. Stop making this a pissing contest with me since I am not interested - although I am flattered my opinion means so much to you.

You really aren't making a lot of sense, why must those two clear drag differences be modeled and simulated in order to make a claim they generate lower drag? F1 cars were designed long before CFD was invented, you know, not everything about aerodynamics has to be run trough CFD to take away some conclusions.

You realize that the diffuser and beam wing performance affect the rear wing, right? And that the flow and design fo the both of those parts are dependent on what is upstream? Ferrari's latest flow vis shows separation on the second element. They're running the wing quite hard.

I can make wings that have less frontal area or even less AOA that are draggy just by changing the airfoil and positioning of the slot gaps

You haven't responded why your unoptimized flowstreams validate that a small sidepod MUST have that rear wheel flowfield. And if you admit that it doesn't, then what is the effect of varying that? You should do a sensitivity study, but either way, it isn't gonna be what W13 is doing, because there is just about 0 chance that you get the vorticity exactly right.

[cplchanb]

You mean the "smaller airbox, smaller rear wing" that you didn't even model in your CFD analysis? so like others are saying, your analysis is a good reference model, but has enough inaccuracies that using this as anything other than just a general guess is probably not very representative. Stop making this a pissing contest with me since I am not interested - although I am flattered my opinion means so much to you.

You really aren't making a lot of sense, why must those two clear drag differences be modeled and simulated in order to make a claim they generate lower drag? F1 cars were designed long before CFD was invented, you know, not everything about aerodynamics has to be run trough CFD to take away some conclusions.

So eyeball CFD - got it

You were semi talking out your ass, we seem to have transitioned to full mode

While we appreciate your efforts and zeal, as people have mentioned, the full car needs to be analyzed in order to have the complete picture, not just the side pods or part of the car. AFAIK, the only people other than the teams and those who have the Williams app that has the full car model is the fia technical dept. Not to mention the computational power required for these cfds, so unless you work in a lab with a super computer, it won't be completely accurate, at least not enough to make such a strong claim

[kfrantzios]

You really aren't making a lot of sense, why must those two clear drag differences be modeled and simulated in order to make a claim they generate lower drag? F1 cars were designed long before CFD was invented, you know, not everything about aerodynamics has to be run trough CFD to take away some conclusions.

So eyeball CFD - got it

You were semi talking out your ass, we seem to have transitioned to full mode

While we appreciate your efforts and zeal, as people have mentioned, the full car needs to be analyzed in order to have the complete picture, not just the side pods or part of the car. AFAIK, the only people other than the teams and those who have the Williams app that has the full car model is the fia technical dept. Not to mention the computational power required for these cfds, so unless you work in a lab with a super computer, it won't be completely accurate, at least not enough to make such a strong claim

Just a note regarding CFD…
CFD does not “teach” you aerodynamics. It is used to validate and optimise a concept. You need to get the concept right in the first place. Do you think that Adrian Newey or any other top designer need CFD simulations to understand flow?

In a scientific point of view, Vanja made a claim and run a simulation to prove it. While the argument that his simulation is not very accurate, as posted by others, is probably correct, it does not prove that the simulation and his claim is wrong.

[mantikos]

So eyeball CFD - got it

You were semi talking out your ass, we seem to have transitioned to full mode

While we appreciate your efforts and zeal, as people have mentioned, the full car needs to be analyzed in order to have the complete picture, not just the side pods or part of the car. AFAIK, the only people other than the teams and those who have the Williams app that has the full car model is the fia technical dept. Not to mention the computational power required for these cfds, so unless you work in a lab with a super computer, it won't be completely accurate, at least not enough to make such a strong claim

Just a note regarding CFD…
CFD does not “teach” you aerodynamics. It is used to validate and optimise a concept. You need to get the concept right in the first place. Do you think that Adrian Newey or any other top designer need CFD simulations to understand flow?

In a scientific point of view, Vanja made a claim and run a simulation to prove it. While the argument that his simulation is not very accurate, as posted by others, is probably correct, it does not prove that the simulation and his claim is wrong.

And we aren't claiming his experiment to prove a hypothesis is wrong - that's the scientific method and we admire him for doing that.

What the rest of us are saying is that it doesn't represent the Mercedes car and therefore isn't directly applicable (and I believe you are saying that too but don't want to put those words in your mouth). So his claim about the W13 is off, however it is accurate about his model.

[AeroDynamic]

Ignore the words, just look at the pretty pictures. Most social media is better consumed that way!

This is technical forum….

I know, but just like with various types of diagrams, you don't need words to learn something useful.

I posted the tweet to specifically answer this question.
viewtopic.php?p=1036177#p1036177

Agree. Images of technical engineering is technical information and knowledge in the form of pictures. The images give you 'data' i.e. you can extract data from what you are seeing to create CFD simulations from home. Or you can understand how something is engineered and how it works. Data and information in images should not be discounted or dismissed in value because its not data or information in the medium of scribes or similar. The visual medium is just as informative and knowledgeable to take from. Their value is equal or arguable.

they say a picture is worth a thousand words

[Vanja #66]

You realize that the diffuser and beam wing performance affect the rear wing, right? And that the flow and design fo the both of those parts are dependent on what is upstream? Ferrari's latest flow vis shows separation on the second element. They're running the wing quite hard.

First of all, there is absolutely no separation on Ferrari rear wing whatsoever. I don't get what you are going at with those other questions, to be honest.

I can make wings that have less frontal area or even less AOA that are draggy just by changing the airfoil and positioning of the slot gaps

In general, yes you can. In motorsport, with high-camber foils for rear wings and using the full top-view surface allowed, you can't. Tried it bunch of times, all high-camber foils have very similar coefficients and slight geometry changes lead to slight coeff. changes. If you keep the chord and reduce AoA, you consequentially reduce both the C_D and frontal area of the rear wing and this is what's going on with all rear wings.

You haven't responded why your unoptimized flowstreams validate that a small sidepod MUST have that rear wheel flowfield. And if you admit that it doesn't, then what is the effect of varying that? You should do a sensitivity study, but either way, it isn't gonna be what W13 is doing, because there is just about 0 chance that you get the vorticity exactly right.

You are right, I haven't responded to you. I responded to mantikos and all of a sudden it felt like it was 3 against one. That's hardly fair play now, isn't it? Now that the mods seem to have deleted his intriguing reply to my last post to him, they indicate that discussion is over. So I'll get back to all your questions later this evening.

[LM10]

You haven't responded why your unoptimized flowstreams validate that a small sidepod MUST have that rear wheel flowfield. And if you admit that it doesn't, then what is the effect of varying that? You should do a sensitivity study, but either way, it isn't gonna be what W13 is doing, because there is just about 0 chance that you get the vorticity exactly right.

You are right, I haven't responded to you. I responded to mantikos and all of a sudden it felt like it was 3 against one. That's hardly fair play now, isn't it? Now that the mods seem to have deleted his intriguing reply to my last post to him, they indicate that discussion is over. So I'll get back to all your questions later this evening.

3 not-so-experts (one of them being a complete armchair-expert and rude on top of that) vs. one expert, though. Seems not fair, that's true.