Aston Martin AMR23

[Vanja #66]

Any idea why there's such a difference in the pressure build up on the rear tyres between the two concepts? Is this a major contributor for AMR23's dragy-ness?

What surprises me a bit is the Mercedes' much lower pressure buildup on the rear tire. Likewise, the rear wing but also the front wing seems to work better on the Mercedes, but the airflow at the sidepod seems a bit uncoordinated. I expect this to get worse with Yaw. But is there something about the simulation that explains the stronger pressure buildup on the rear tire of the AM as well as what i noticed about the front and rear wing? Or were the conditions the same? I'm looking forward to part II.

In this simulation, W14 rear tyre drag was due to mid wing vortex hitting it, which may or may not hit the tyre in the same way and place on the actual car.

viewtopic.php?p=1112827#p1112827

Andi, there are yaw simulation results in part 2 and 3 and we are covering more topics there. Sadly, a day has 24h only so it takes some time to prepare the actual video even if the material is already there

[Andi76]

Any idea why there's such a difference in the pressure build up on the rear tyres between the two concepts? Is this a major contributor for AMR23's dragy-ness?

What surprises me a bit is the Mercedes' much lower pressure buildup on the rear tire. Likewise, the rear wing but also the front wing seems to work better on the Mercedes, but the airflow at the sidepod seems a bit uncoordinated. I expect this to get worse with Yaw. But is there something about the simulation that explains the stronger pressure buildup on the rear tire of the AM as well as what i noticed about the front and rear wing? Or were the conditions the same? I'm looking forward to part II.

In this simulation, W14 rear tyre drag was due to mid wing vortex hitting it, which may or may not hit the tyre in the same way and place on the actual car.

viewtopic.php?p=1112827#p1112827

Andi, there are yaw simulation results in part 2 and 3 and we are covering more topics there. Sadly, a day has 24h only so it takes some time to prepare the actual video even if the material is already there

Yes it would be good if the day had 48 hours, I also think to myself often...thanks for your great work! I look forward to part II and III!

[CriXus]

Isn't having more red on the tires means more drag, if so the AMR32 has more drag than W14? What's is causing that on AMR32?

[ringo]

It will always have more drag. The W14 has no sidepods. But I think before going deeper into the discussion, so as not to siderail the thread. Vanja could maybe share how much downforce and drag his models generate for comparision.
If you do not want to share the actual Newton or Pound force, that is fine. But at least use the best car as the reference, and let the other cars be a fraction of that. If Shub is reading this, he better do it in his next video. It can appear is if snake oil is being sold, if only talking about colours is accurate. Also some of the claims may in fact not be accurate. I would kindly suggest something like this:

Example: RB 3000lb downforce = 1.0 factor.
AMR23 2800 lb = 2800/3000 = 0.93
W14 = 2000lb = 0.67

and like wise drag and L/D.

Actual factors would give better perspective than just trying interpret shades; more so for our colour blind forum members.
I am not surprised W14 has less drag. It simply just needs bigger wings to generate grip.

[Vanja #66]

In these 2 simulations (yaw 0 deg):

AMR23-sidepod-model:
Downforce 4663N
Drag 2349N

W14-sidepod-model:
Downforce 5270N
Drag 2371N

How come more drag on W14? Front wing is bigger on W14 model and more loaded in centre, I had some trouble with waterslide separation deep down, so I unloaded central section on AMR completely (more than the actual car I believe). This is the entire reason for those overall differences, rear tyre drag values are very close (922N and 911N respectively) - because rear tyre squirt behaved differently on W14 and dropped the pressure on the rear more, generating more drag. I wouldn't presume pointing to such important features from these simulations and say they have some meaning, tyre squirt is far more complex than front tyre surface pressure field.

And this is exactly why I didn't want to post absolute numbers a year ago - models are very, very limited and we can only use them to observe possible behaviour around sidepods and draw some limited conclusions from potential phenomena occurring there.

[ringo]

In these 2 simulations (yaw 0 deg):

AMR23-sidepod-model:
Downforce 4663N
Drag 2349N

W14-sidepod-model:
Downforce 5270N
Drag 2371N

How come more drag on W14? Front wing is bigger on W14 model and more loaded in centre, I had some trouble with waterslide separation deep down, so I unloaded central section on AMR completely (more than the actual car I believe). This is the entire reason for those overall differences, rear tyre drag values are very close (922N and 911N respectively) - because rear tyre squirt behaved differently on W14 and dropped the pressure on the rear more, generating more drag. I wouldn't presume pointing to such important features from these simulations and say they have some meaning, tyre squirt is far more complex than front tyre surface pressure field.

And this is exactly why I didn't want to post absolute numbers a year ago - models are very, very limited and we can only use them to observe possible behaviour around sidepods and draw some limited conclusions from potential phenomena occurring there.

Thank you for the numbers sir.
I feel more connected to the simulations now, more than Hamilton is to the W14.

I see why you did not want to post the numbers, so as not to mislead, but it still provides a deeper perspective on what was done and what had to be adjusted. The numbers can drive bias, or remove bias, depending on intentions. if you don't see what you like you can tweak a wing or tuck in a sidepod belly to tweak the results to how you want it, or.. the numbers can indicate a missed detail, and upon correction you end up with a more accurate model which is the right thing to do. But for me at least, I get a feel of the challenges you experienced with the modeling, given that we cannot expect you to have 100% precision with wing profiles, tyre squirt etcetera.

The Lift to drag is too good for W14, and this is maybe why Mike Elliot is scratching his head. Probably got similar results.
Or it can be correct, but that value only exists in an instant in reality and 90% the rest of the time the attitude of the car is not ideal and it's making less than the AMR23.

[Vanja #66]

-ClS (downforce) figure is less than half of what the actual cars have, floor and wings are simply lacking. The original model, made by jjn9128, was intended for simple visualisation of major changes in major flow structures between (then) 2019 and 2021 cars and the article was written in December 2019.

https://www.f1technical.net/features/22288

For W14 and AMR23 I actually levelled the car (base model was made with rake) and set the ride height (from plank) at 30mm. If it was 10mm, -ClS could be better, but that's not what the simulation was about So L/D and other numbers are skewed quite badly...

[Hoffman900]

While I think these models are fun and illustrative, calling them the W14 and AMR23 is misleading. They aren’t either cars and you are likely missing a lot of things that will effect either flow fields, in addition to CFD being inherently wrong (without a ton of correlation work in the wind tunnel and on track).

[Vanja #66]

It literally says so few posts above...

I honestly can't roll my eyes hard enough. Is every attempt to put forward something illustrative and useful in trying to demystify anything about F1 aero condemned to bucket loads of pointless comments and endless string of cr@p trying to disprove everything about it? What exactly is the problem with me doing these simulations and presenting results?

Anyone who doesn't like it is free to ignore it, I'm not gonna post a 10k-character-long disclaimer every time I discuss this so you might as well ignore it altogether or block my posts and be done with it.

XOXO

V

[Hoffman900]

It literally says so few posts above...

I honestly can't roll my eyes hard enough. Is every attempt to put forward something illustrative and useful in trying to demystify anything about F1 aero condemned to bucket loads of pointless comments and endless string of cr@p trying to disprove everything about it? What exactly is the problem with me doing these simulations and presenting results?

Anyone who doesn't like it is free to ignore it, I'm not gonna post a 10k-character-long disclaimer every time I discuss this so you might as well ignore it altogether or block my posts and be done with it.

XOXO

V

That is not how your co-presenter is selling it on Youtube. I get it gets clicks, but from one engineer to another, it’s only applicable to the designs you used and the mesh / computing you used as well. It’s not the W14 or the AMR23 and it’s not reality.

[604gtir]

It literally says so few posts above...

I honestly can't roll my eyes hard enough. Is every attempt to put forward something illustrative and useful in trying to demystify anything about F1 aero condemned to bucket loads of pointless comments and endless string of cr@p trying to disprove everything about it? What exactly is the problem with me doing these simulations and presenting results?

Anyone who doesn't like it is free to ignore it, I'm not gonna post a 10k-character-long disclaimer every time I discuss this so you might as well ignore it altogether or block my posts and be done with it.

XOXO

V

I like your posts and work and the videos. Keep making them please. I'm not an engineer by trade, but still find it very interesting as I've been an F1 fan for 35 years. Keep in mind, for every loud angry voice there's dozens quietly who enjoy it.

[Hoffman900]

It literally says so few posts above...

I honestly can't roll my eyes hard enough. Is every attempt to put forward something illustrative and useful in trying to demystify anything about F1 aero condemned to bucket loads of pointless comments and endless string of cr@p trying to disprove everything about it? What exactly is the problem with me doing these simulations and presenting results?

Anyone who doesn't like it is free to ignore it, I'm not gonna post a 10k-character-long disclaimer every time I discuss this so you might as well ignore it altogether or block my posts and be done with it.

XOXO

V

I like your posts and work and the videos. Keep making them please. I'm not an engineer by trade, but still find it very interesting as I've been an F1 fan for 35 years. Keep in mind, for every loud angry voice there's dozens quietly who enjoy it.

It’s not about not enjoying it, it’s about people still quoting it a year later as if it’s fact. I enjoy it, but I know it’s technically wrong.

It’s entertainment, not tech.

[604gtir]

It literally says so few posts above...

I honestly can't roll my eyes hard enough. Is every attempt to put forward something illustrative and useful in trying to demystify anything about F1 aero condemned to bucket loads of pointless comments and endless string of cr@p trying to disprove everything about it? What exactly is the problem with me doing these simulations and presenting results?

Anyone who doesn't like it is free to ignore it, I'm not gonna post a 10k-character-long disclaimer every time I discuss this so you might as well ignore it altogether or block my posts and be done with it.

XOXO

V

I like your posts and work and the videos. Keep making them please. I'm not an engineer by trade, but still find it very interesting as I've been an F1 fan for 35 years. Keep in mind, for every loud angry voice there's dozens quietly who enjoy it.

It’s not about not enjoying it, it’s about people still quoting it a year later as if it’s fact. I enjoy it, but I know it’s technically wrong.

It’s entertainment, not tech.

exactly its entertainment, does it bother you that much ?

[Hoffman900]

:

I like your posts and work and the videos. Keep making them please. I'm not an engineer by trade, but still find it very interesting as I've been an F1 fan for 35 years. Keep in mind, for every loud angry voice there's dozens quietly who enjoy it.

It’s not about not enjoying it, it’s about people still quoting it a year later as if it’s fact. I enjoy it, but I know it’s technically wrong.

It’s entertainment, not tech.

exactly its entertainment, does it bother you that much ?

Yes because it’s going to be quoted as fact in technical discussions like last year’s exercises was.

You call it a “cfd analysis of sidepod designs” without selling it as an analysis of the W14 and AMR23.

It sounds like I’m arguing semantics, but I’m not.

[Vanja #66]

That is not how your co-presenter is selling it on Youtube. I get it gets clicks, but from one engineer to another, it’s only applicable to the designs you used and the mesh / computing you used as well. It’s not the W14 or the AMR23 and it’s not reality.

Feel free to use comment section on the video and let him know. Feel free to make your own models and do your own CFD and share the results, then we'd actually have something worth discussing from your side.

And don't forget to leave that entertainment remark on youtube video.