RB VCARB 03

[matteosc]

I don't really have exact sources, but I could give a summary to the best of my understanding.

The battery is one of the limiting factors. Batteries are very nasty to work with because they are thermally very sensitive and have a specific optimum temperature window that needs to be maintained for best performance (not to mention the thermal degradation but that's less of a problem since batteries don't need to last for ages anyway). And the fact that there's a lot more reliance in electric power, means that the batteries will undergo more cycles in a lap. mguk is bigger to account for mguh loss + increased expected electric energy output, which means higher harvesting under breaking and more heat in both battery and mguk (and the whole electrical system, including the wires). When it comes to batteries, you really have no choice if you want them to work properly. You have to keep the batteries "happy" at all times. Which is damn hard to achieve with what they're asking the batteries to do with these new regs, but you have to try your best anyway.

There's more things to consider as well. For example, the mguh being gone, which was an element that took quite a bit of residual heat from the turbos through exhaust gasses to convert it to power and now it is no longer part of these power units. Now there is a small caveat here, the ICEs are practically detuned so you would expect less heat from it, however, it's still something to consider. With the mguh gone, you probably need to add in a bit to the cooling requirements of the exhaust system (or have bigger radiators).

And finally, even though this is practically negligible, the cars are smaller. It's generally harder to have a tight packaged car when you have less room to work with, considering you have to fit these complicated PUs alongside the exhaust system and the gearbox as well. However, the size difference is hardly significant, so the effect it has on cooling is probably nothing. Just something worth mentioning.

I agree with almost everything except for the "detuning" thermal engine, which in my opinion will end up producing more heat (see my post before).

[FrukostScones]

[Emag]

I don't really have exact sources, but I could give a summary to the best of my understanding.

The battery is one of the limiting factors. Batteries are very nasty to work with because they are thermally very sensitive and have a specific optimum temperature window that needs to be maintained for best performance (not to mention the thermal degradation but that's less of a problem since batteries don't need to last for ages anyway). And the fact that there's a lot more reliance in electric power, means that the batteries will undergo more cycles in a lap. mguk is bigger to account for mguh loss + increased expected electric energy output, which means higher harvesting under breaking and more heat in both battery and mguk (and the whole electrical system, including the wires). When it comes to batteries, you really have no choice if you want them to work properly. You have to keep the batteries "happy" at all times. Which is damn hard to achieve with what they're asking the batteries to do with these new regs, but you have to try your best anyway.

There's more things to consider as well. For example, the mguh being gone, which was an element that took quite a bit of residual heat from the turbos through exhaust gasses to convert it to power and now it is no longer part of these power units. Now there is a small caveat here, the ICEs are practically detuned so you would expect less heat from it, however, it's still something to consider. With the mguh gone, you probably need to add in a bit to the cooling requirements of the exhaust system (or have bigger radiators).

And finally, even though this is practically negligible, the cars are smaller. It's generally harder to have a tight packaged car when you have less room to work with, considering you have to fit these complicated PUs alongside the exhaust system and the gearbox as well. However, the size difference is hardly significant, so the effect it has on cooling is probably nothing. Just something worth mentioning.

I agree with almost everything except for the "detuning" thermal engine, which in my opinion will end up producing more heat (see my post before).

Interesting take. I don't have the expertise to comment with confidence in this topic, but what you said seems plausible. I was just looking at it from a simpler perspective but I did not consider the overall efficiency drop.

[AR3-GP]

In 2026 you have almost 3x electrical power output from battery and MGU-K and much more energy recovery than before, so cooling requirements are also higher, also operating temperatures of those components are much lower than ICE. So even tho there is less heat energy produced by electrical part of the PU, it can be difficult to get rid of it when operating temperatures are not that higher than ambient air temperatures which you use to cool it down.

1) Cars reach their top speeds much faster now, therefore there's a big increase in the cooling power around the lap.

[Badger]

In 2026 you have almost 3x electrical power output from battery and MGU-K and much more energy recovery than before, so cooling requirements are also higher, also operating temperatures of those components are much lower than ICE. So even tho there is less heat energy produced by electrical part of the PU, it can be difficult to get rid of it when operating temperatures are not that higher than ambient air temperatures which you use to cool it down.

1) Cars reach their top speeds much faster now, therefore there's a big increase in the cooling power around the lap.

https://i.postimg.cc/zfk604cN/image.png

I don't trust that graph at all. The engines have the same amount of power at full deployment, so why would the difference be that massive below 250 kph? Drag isn't that much, and the 2026 engine starts to taper quite early.

[wiktor977]

I don't really have exact sources, but I could give a summary to the best of my understanding.

The battery is one of the limiting factors. Batteries are very nasty to work with because they are thermally very sensitive and have a specific optimum temperature window that needs to be maintained for best performance (not to mention the thermal degradation but that's less of a problem since batteries don't need to last for ages anyway). And the fact that there's a lot more reliance in electric power, means that the batteries will undergo more cycles in a lap. mguk is bigger to account for mguh loss + increased expected electric energy output, which means higher harvesting under breaking and more heat in both battery and mguk (and the whole electrical system, including the wires). When it comes to batteries, you really have no choice if you want them to work properly. You have to keep the batteries "happy" at all times. Which is damn hard to achieve with what they're asking the batteries to do with these new regs, but you have to try your best anyway.

There's more things to consider as well. For example, the mguh being gone, which was an element that took quite a bit of residual heat from the turbos through exhaust gasses to convert it to power and now it is no longer part of these power units. Now there is a small caveat here, the ICEs are practically detuned so you would expect less heat from it, however, it's still something to consider. With the mguh gone, you probably need to add in a bit to the cooling requirements of the exhaust system (or have bigger radiators).

And finally, even though this is practically negligible, the cars are smaller. It's generally harder to have a tight packaged car when you have less room to work with, considering you have to fit these complicated PUs alongside the exhaust system and the gearbox as well. However, the size difference is hardly significant, so the effect it has on cooling is probably nothing. Just something worth mentioning.

MGU-H name is misleading, it didn't take any heat out of the system. I would say that on its own it was another heat source in PU. MGU-H used the kinetic energy of the exhaust gases that propelled the turbocharger to charge the battery or it could dump the energy from the battery to spool up the turbocharger to reduce the turbo lag.

[karana]

Honest question: What is the reasoning behind this stance?
As I see it, Thermal Efficiency of the ICE should be one of the highest priorities on everyone's list in order to maximize usable power and energy recovery for the max. 833 KW provided. The same goes for the whole electrical part, which should be well above 90% TE for recovery as well as supply. So there is not a lot of heat to be produced by the latter one.
What else is there that should require lots of cooling?
I would rather suspect, that centre line cooling does not cost a lot of already much less RW downforce, while giving you design freedom for the sidepods in order to work the floor as good as you can.

In 2026 you have almost 3x electrical power output from battery and MGU-K and much more energy recovery than before, so cooling requirements are also higher, also operating temperatures of those components are much lower than ICE. So even tho there is less heat energy produced by electrical part of the PU, it can be difficult to get rid of it when operating temperatures are not that higher than ambient air temperatures which you use to cool it down.

Actually I would argue that there is more heat coming from the PU. If I am not mistaken the fuel flow should be approximately the same (with the caviat of being energy-based rather than volume-based), but the power is reduced, mainly through a lower compression ratio. This means that less mechanical power is produced with the same amount of energy in the fuel, therefore the thermal losses must be higher.
The electrical part will contribute, but a ~90% energy conversion (electric) produces less heat than a ~45% one (thermal engine).

The fuel energy flow is reduced quite a lot, from ~4300MJ/hr to 3000MJ/hr, that's where the power reduction comes from.

[Emag]

I don't really have exact sources, but I could give a summary to the best of my understanding.

The battery is one of the limiting factors. Batteries are very nasty to work with because they are thermally very sensitive and have a specific optimum temperature window that needs to be maintained for best performance (not to mention the thermal degradation but that's less of a problem since batteries don't need to last for ages anyway). And the fact that there's a lot more reliance in electric power, means that the batteries will undergo more cycles in a lap. mguk is bigger to account for mguh loss + increased expected electric energy output, which means higher harvesting under breaking and more heat in both battery and mguk (and the whole electrical system, including the wires). When it comes to batteries, you really have no choice if you want them to work properly. You have to keep the batteries "happy" at all times. Which is damn hard to achieve with what they're asking the batteries to do with these new regs, but you have to try your best anyway.

There's more things to consider as well. For example, the mguh being gone, which was an element that took quite a bit of residual heat from the turbos through exhaust gasses to convert it to power and now it is no longer part of these power units. Now there is a small caveat here, the ICEs are practically detuned so you would expect less heat from it, however, it's still something to consider. With the mguh gone, you probably need to add in a bit to the cooling requirements of the exhaust system (or have bigger radiators).

And finally, even though this is practically negligible, the cars are smaller. It's generally harder to have a tight packaged car when you have less room to work with, considering you have to fit these complicated PUs alongside the exhaust system and the gearbox as well. However, the size difference is hardly significant, so the effect it has on cooling is probably nothing. Just something worth mentioning.

MGU-H name is misleading, it didn't take any heat out of the system. I would say that on its own it was another heat source in PU. MGU-H used the kinetic energy of the exhaust gases that propelled the turbocharger to charge the battery or it could dump the energy from the battery to spool up the turbocharger to reduce the turbo lag.

Well I tried to simplify it. And it's true that the MGU-H didn't literally remove heat from the exhaust. As you said, it converts turbine kinetic energy to electricity. However, this indirectly reduces energy going into waste heat downstream. So I don't believe the assessment of exhausts requiring more cooling without the mguh is wrong.

[wiktor977]

In 2026 you have almost 3x electrical power output from battery and MGU-K and much more energy recovery than before, so cooling requirements are also higher, also operating temperatures of those components are much lower than ICE. So even tho there is less heat energy produced by electrical part of the PU, it can be difficult to get rid of it when operating temperatures are not that higher than ambient air temperatures which you use to cool it down.

1) Cars reach their top speeds much faster now, therefore there's a big increase in the cooling power around the lap.

https://i.postimg.cc/zfk604cN/image.png

I think that because of a slower pace per lap (slower average speed) heat rejection via air-cooled radiators can be worse in 2026, but there are too many other variables to be sure about that.

[Owen.C93]

I don't really have exact sources, but I could give a

MGU-H name is misleading, it didn't take any heat out of the system. I would say that on its own it was another heat source in PU. MGU-H used the kinetic energy of the exhaust gases that propelled the turbocharger to charge the battery or it could dump the energy from the battery to spool up the turbocharger to reduce the turbo lag.

We’re off topic. But the MGU-H did extract heat energy due to the way the exhaust gas cools over the turbo impeller which causes a pressure differential. That’s how it derived its energy efficiency enhancements, rather than just extra parasitic drag charging a battery which is what they could use the MGU-K for.

[mzso]

This explanation to me means that we can expect bigger airboxes in general. It's not for the ICE, it's for the hybrid system which makes perfect sense.

This tweet is missing

[Owen.C93]

https://www.youtube.com/watch?v=3j6G-XM7mRc

You can see those flicks on the edge of the diffuser I mentioned earlier. Looks like they’re part of the wheel assembly but extended inboard as far as possible.

Still need some better pictures though, but potentially that will be a theme on some cars.

[wiktor977]

I don't really have exact sources, but I could give a summary to the best of my understanding.

The battery is one of the limiting factors. Batteries are very nasty to work with because they are thermally very sensitive and have a specific optimum temperature window that needs to be maintained for best performance (not to mention the thermal degradation but that's less of a problem since batteries don't need to last for ages anyway). And the fact that there's a lot more reliance in electric power, means that the batteries will undergo more cycles in a lap. mguk is bigger to account for mguh loss + increased expected electric energy output, which means higher harvesting under breaking and more heat in both battery and mguk (and the whole electrical system, including the wires). When it comes to batteries, you really have no choice if you want them to work properly. You have to keep the batteries "happy" at all times. Which is damn hard to achieve with what they're asking the batteries to do with these new regs, but you have to try your best anyway.

There's more things to consider as well. For example, the mguh being gone, which was an element that took quite a bit of residual heat from the turbos through exhaust gasses to convert it to power and now it is no longer part of these power units. Now there is a small caveat here, the ICEs are practically detuned so you would expect less heat from it, however, it's still something to consider. With the mguh gone, you probably need to add in a bit to the cooling requirements of the exhaust system (or have bigger radiators).

And finally, even though this is practically negligible, the cars are smaller. It's generally harder to have a tight packaged car when you have less room to work with, considering you have to fit these complicated PUs alongside the exhaust system and the gearbox as well. However, the size difference is hardly significant, so the effect it has on cooling is probably nothing. Just something worth mentioning.

MGU-H name is misleading, it didn't take any heat out of the system. I would say that on its own it was another heat source in PU. MGU-H used the kinetic energy of the exhaust gases that propelled the turbocharger to charge the battery or it could dump the energy from the battery to spool up the turbocharger to reduce the turbo lag.

Well I tried to simplify it. And it's true that the MGU-H didn't literally remove heat from the exhaust. As you said, it converts turbine kinetic energy to electricity. However, this indirectly reduces energy going into waste heat downstream. So I don't believe the assessment of exhausts requiring more cooling without the mguh is wrong.

True, that it reduce exhaust gases temperature but I don't think it would be that different with or without MGU-H when it comes to the cooling requirements of the turbocharger, but I might be wrong.

[AR3-GP]

Well I tried to simplify it. And it's true that the MGU-H didn't literally remove heat from the exhaust. As you said, it converts turbine kinetic energy to electricity. However, this indirectly reduces energy going into waste heat downstream. So I don't believe the assessment of exhausts requiring more cooling without the mguh is wrong.

Why does the exhaust need to be cooled more? I don't get it. I think there's just a big misunderstanding and lack of framework for understanding what is going on here.

The MGU-H spins at 100,000 RPM. It generated heat and needed to be actively cooled. Its removal has eliminated a significant heat generating source.

Exhaust cooling isn't really a thing. Teams are trying to trap the heat inside the exhaust to prevent it from radiating into the engine cover compartment. Sometimes there are wraps to trap the heat inside the pipes.

[TeamKoolGreen]

Lindblads spin caught on camera. Yes it's cold and wet. But there is 35% less downforce

https://x.com/i/status/2013719714933916152

We never see spins at shakedowns. We barely seen spins at full on testing in 2022.

This spin could be a sign of things to come. People thought porpoising was bad...