Mercedes Power Unit Hardware & Software

[hurril]

If they have a separate circuitry for the water intercooler, they could be opting to by-pass it on the straights to rely on the air intercooler instead. That way the coolant get to be colder for when they need it in slower areas. An alternative would be to have another water radiator, but that would be heavier.

[Blackout]

Yes Mercedes do use two different intercoolers...
http://www.f1technical.net/forum/viewto ... 60#p605840

[Alexgtt]

You know i think this engine may use both air and water intercoolers. Ferrari seems to be doing it, and ferrari may in fact stole that idea from Mercedes.
Theoretically there is more control over the cooling of the engine with the water intercooler because there is control over a water pump which may be electrical.
Any rules regarding cooling pumps, and them being mechanical or electrical?

Mechanically driven. However, not sure coolant pump would need to deliver 10bar. Seems high to me so maybe they are electric? Reg copied below. Not sure about 2017 but expect same.

5.13 Engine ancillaries :
All coolant pumps, oil pumps, scavenge pumps, oil/air separators, hydraulic pumps and fuel
pumps delivering more than 10bar must be mechanically driven directly from the engine
and/or MGU-K with a fixed speed ratio.

[godlameroso]

You know i think this engine may use both air and water intercoolers. Ferrari seems to be doing it, and ferrari may in fact stole that idea from Mercedes.
Theoretically there is more control over the cooling of the engine with the water intercooler because there is control over a water pump which may be electrical.
Any rules regarding cooling pumps, and them being mechanical or electrical?

Mechanically driven. However, not sure coolant pump would need to deliver 10bar. Seems high to me so maybe they are electric? Reg copied below. Not sure about 2017 but expect same.

5.13 Engine ancillaries :
All coolant pumps, oil pumps, scavenge pumps, oil/air separators, hydraulic pumps and fuel
pumps delivering more than 10bar must be mechanically driven directly from the engine
and/or MGU-K with a fixed speed ratio.

Most radiators run no more than 1.8 bar absolute, so less than 10 bar isn't a problem.

[PlatinumZealot]

I think it is electric for efficiency reasons.

[Facts Only]

It's definitely mechanical.

[PlatinumZealot]

So how is the flow rate managed? By re-circulation?
I know a lot of modern cars, especially The BMW M5, has a thermal management computer that alters different valves and pump speed to control temperature - generally to increase efficiency.

[Alexgtt]

You know i think this engine may use both air and water intercoolers. Ferrari seems to be doing it, and ferrari may in fact stole that idea from Mercedes.
Theoretically there is more control over the cooling of the engine with the water intercooler because there is control over a water pump which may be electrical.
Any rules regarding cooling pumps, and them being mechanical or electrical?

Mechanically driven. However, not sure coolant pump would need to deliver 10bar. Seems high to me so maybe they are electric? Reg copied below. Not sure about 2017 but expect same.

5.13 Engine ancillaries :
All coolant pumps, oil pumps, scavenge pumps, oil/air separators, hydraulic pumps and fuel
pumps delivering more than 10bar must be mechanically driven directly from the engine
and/or MGU-K with a fixed speed ratio.

Most radiators run no more than 1.8 bar absolute, so less than 10 bar isn't a problem.

No, I meant the regulation says any pump that delivers more than 10 Bar have to be mechanically driven. Therefore the question is, how much pressure does the water pump have to deliver? Under 10 bar and the option opens up to an electric pump. Over 10 bar and you have to use mechanical pump.

I strongly suspect a water pump in an F1 engine doesn't deliver 10 bar. What pressure do the engines water systems operate at?

[godlameroso]

No more than 2.1 bar, at least that I've seen

[tok-tokkie]

A radiator that can handle >10 bar wold be some piece of work. And for what thermal advantage? At 10 bar (gauge) the temp of boiling water is 184°C. Just what you don't want for a cooling device.

[ringo]

The inter cooler water can have a separate electric pump for it's circuit; while the engine's pump can remain mechanical. I don't think it needs to be on the same circuit as the engine coolant. I have seen the radiators used on some of the cars with multiple inlets and outlets suggesting multiple cores.
It's likely there are separate closed circuits that just share the same radiator body.

[hurril]

A radiator that can handle >10 bar wold be some piece of work. And for what thermal advantage? At 10 bar (gauge) the temp of boiling water is 184°C. Just what you don't want for a cooling device.

Why not? There are benefits to running a hotter cooling medium.

[godlameroso]

Doesn't aluminum begin to lose structural stiffness at ~200c?

[gruntguru]

Two points. Heat exchangers to handle 10 bar are not unusual. (The intercoolers on F1 cars take at least 3 bar.)

A 10 bar cooling system does not mean you need a 10 bar pump. If pump inlet is 9 bar and discharge is 10 bar - you have a 1 bar pump.

[ringo]

You have to develop that pressure somewhere. Something has to generate that 9 bar of pressure if you insist that's the suction pressure of the pump. It could be from heating the water, but that is not likely at all from 1 bar to 9 solely from heating. It would not be desirable.
But i don't think there is a need for such high pressure as the physical properties of the water wont change much.
Also you are looking at heavier construction with containing 10 bar pressure as opposed to 3 bars.