Brake Ducts, Tire Cooling, and beyond

[pantherxxx]

[AutoRacer.it] McLaren: Other teams are trying to copy a secret of the MCL39

Source: https://autoracer.it/it/mclaren-segreto ... eni-rivali

[Rinde]

Assuming that whatever McLaren is doing has been in development since 2022 and the FIA can't pinpoint whatever it is, that means a 3-year R&D period that other teams need to catch up.

[Watto]

I doubt PCM technology because liquid cooling of the brakes is forbidden according to article 11.5.

https://i.postimg.cc/CMQtHJ56/image.png

Idea of PCM is not to use it for cooling of the brakes, it would be used to serve as a barrier between hot brakes and the wheels. Kind of like a insulator but that starts working at certain temperature, so you can gets some heat into the tire but not more than that.

Not sure if that would fall under "no liquid cooling", maybe, who knows.

A material inside the brake drum which at some point is liquid would

I guess a few thoughts B Sports though that a lining inside the drum cover so its unlikely I think to be cooling the brakes rather a barrier on heat escaping.

I wonder with AR3-GP mentioning something about the McLaren being draggier the DRS difference now being as high as other teams would this mean more air is required to released inside the drum - much like insulation maintaining a temp ins a house or what have you it could naturally build so more air required to move it out of the drums be causing drag?

A 2nd thought that could tie into this. Could it be a material that doesn't change phase to well above what ever temperates they are working with inside the covers? If the phase change occurs at say - and pull from the air only 300c but the drum lining only generally reaches 150-200c its extremely unlikely to ever reach a liquid state.

[.poz]

I doubt PCM technology because liquid cooling of the brakes is forbidden according to article 11.5.

you can go around the rule with sublimation

[langedweil]

I bet a few teams are F5'ing this page for ideas, including McL to see if the competition might be out on track to unwrap the full idea/innovation ...

[Hoffman900]

I bet a few teams are F5'ing this page for ideas, including McL to see if the competition might be out on track to unwrap the full idea/innovation ...

Only if they want a laugh.

Sublimation? Guys, instead of word vomiting, think this one through.

I know B Sport worked in a team, but his job / side gig now is clicks. He is known for outlandish takes for views. It’s working, apparently.

[Hoffman900]

Brake fluid doesn’t move. That’s how hydraulics work.

It doesn't need to move to conduct heat. It's a fluid. Establish a temperature gradient and heat "flows". I know that you could transfer much more heat if you could circulate it, but that is not an insurmountable challenge either. Fluids can be circulated under high pressure (gas pipelines work, somehow). This is where it all starts to get dodgy though. What would such a system look like to the FIA?

I'm also not claiming this is exactly how a system would work, but there could be possibilities along these lines. Maybe one could develop a bespoke brake fluid for such purposes.

Mclaren is clearly doing something that no one has thought of yet. So it's time to think outside of the box.

The hot fluid is mostly contained to the caliper and the immediate vicinity.

If you ever bled brakes in a race car (which you do often), you’d see the fluid coming out of the caliper usually ends up discolored, but quickly cleans up.

[boiler]

Assuming that whatever McLaren is doing has been in development since 2022 and the FIA can't pinpoint whatever it is, that means a 3-year R&D period that other teams need to catch up.

I think we now know why they had brake issues in testing a few years ago.....

[TwanV]

Well a very simple idea would be to have a non return valve in the circuit and ensure continuous circulation of brake fluid in the direction upstream the actual brake fluid line : the non return valve would close immediately on applying sufficient brake pressure. Could explain Norris ' brake issue in China but I doubt it, clearly liquid cooling so clearly illegal not to mention the safety aspect.

[AR3-GP]

Well a very simple idea would be to have a non return valve in the circuit and ensure continuous circulation of brake fluid in the direction upstream the actual brake fluid line : the non return valve would close immediately on applying sufficient brake pressure. Could explain Norris ' brake issue in China but I doubt it, clearly liquid cooling so clearly illegal.

Liquid cooling of the brakes is illegal, but cooling of brake fluid to avoid boiling (and thus a safety issue) is not well defined. Brake fluid and brake lines are unavoidable and they can transport heat. Maybe a team could exploit this.

[AR3-GP]

The hot fluid is mostly contained to the caliper and the immediate vicinity.

If you ever bled brakes in a race car (which you do often), you’d see the fluid coming out of the caliper usually ends up discolored, but quickly cleans up.

Your observation is consistent with the theory. The browning occurs where the temperature is high, and not where the temperature is low. That temperature gradient from high to low is the driving force for heat to flow through the fluid circuit. You could develop a braking fluid with a very high thermal conductivity (in collaboration with Motul or whoever). You could have an inline heat exchanger on the chassis side and argue it is for safety reasons (preventing boiling). etc etc. Not a far-fetched idea.

I only considered it because of the strange/evasive remarks from Mclaren after China from what could easily have been explained away as master cylinder leak...Maybe they had a leak in a heat exchanger...I wouldn't want anyone to know that my brake fluid circuit has a heat exchanger...

[FNTC]

[Farnborough]

The hot fluid is mostly contained to the caliper and the immediate vicinity.

If you ever bled brakes in a race car (which you do often), you’d see the fluid coming out of the caliper usually ends up discolored, but quickly cleans up.

Your observation is consistent with the theory. The browning occurs where the temperature is high, and not where the temperature is low. That temperature gradient from high to low is the driving force for heat to flow through the fluid circuit. You could develop a braking fluid with a very high thermal conductivity (in collaboration with Motul or whoever). You could have an inline heat exchanger on the chassis side and argue it is for safety reasons (preventing boiling). etc etc. Not a far-fetched idea.

I only considered it because of the strange/evasive remarks from Mclaren after China from what could easily have been explained away as master cylinder leak...Maybe they had a leak in a heat exchanger...I wouldn't want anyone to know that my brake fluid circuit has a heat exchanger...

There's "intermediate" device in the rear brake line to proportion the rear retardation between the regenerative part, then moving toward pure friction of disc usage and all without driver input to be ultimately invisible to him.

Look up BBW if you're unaware of the system used.

[Cs98]

Maybe they are putting spearmint chewing gum on the inside of the cake tin.

[AR3-GP]

The hot fluid is mostly contained to the caliper and the immediate vicinity.

If you ever bled brakes in a race car (which you do often), you’d see the fluid coming out of the caliper usually ends up discolored, but quickly cleans up.

Your observation is consistent with the theory. The browning occurs where the temperature is high, and not where the temperature is low. That temperature gradient from high to low is the driving force for heat to flow through the fluid circuit. You could develop a braking fluid with a very high thermal conductivity (in collaboration with Motul or whoever). You could have an inline heat exchanger on the chassis side and argue it is for safety reasons (preventing boiling). etc etc. Not a far-fetched idea.

I only considered it because of the strange/evasive remarks from Mclaren after China from what could easily have been explained away as master cylinder leak...Maybe they had a leak in a heat exchanger...I wouldn't want anyone to know that my brake fluid circuit has a heat exchanger...

There's "intermediate" device in the rear brake line to proportion the rear retardation between the regenerative part, then moving toward pure friction of disc usage and all without driver input to be ultimately invisible to him.

Look up BBW if you're unaware of the system used.

Yes I know, the BBW module is pointed out in regulations. So that's why I can't understand the need to be secretive about the issue. Unless it leaks from something unusual and for which it would not be productive to reveal...