Water Temps

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
Scootin159
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Water Temps

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What water temps do they run in modern F1?

I was thinking about this today, and was thinking it may seem obvious, but they probably don't run the same temp range as a production vehicle. My thought process is that if a hotter radiator will see a larger temperature delta to the cooling airflow, and therefore will transfer more heat to the air. Theoretically this allow for more total cooling potential from a smaller radiator, and therefore less drag.

However, if everything was that simple, why don't see road cars with high coolant temps, and tiny radiators? There must be some drawbacks, and these are what I thought of:

1) Higher water temps, mean higher engine operating temps. That means your tolerances would need to be designed for that higher operating range. A road car needs to work at -20*, as well as at operating temp, so the lower you make that upper bound, the less range you need to cover. F1 cars on the other hand never operate below operating temp, as they pre-heat the coolant before startup.

2) Those higher operating temps will also mean you need to select materials that are stable at those temps. I know super-exotic materials like Berrylium are now banned in F1, but I still imagine they aren't using the same materials as road cars.

3) In order to go over 100*c, you need to run a pressurized system. The higher the temperature, the higher the pressures required. On a road car, a system with super critical 500* water would be a huge safety hazard. On F1, that's probably more acceptable.

4) Higher operating temps would also mean more heat transfer to the in take air through the intake manifold itself. This can probably be mitigated with heat shielding though.

5) Higher operating temps could also cause combustion issues. Wouldn't pre-detonation be more likely when your air-fuel mixture meets a hotter piston/cylinder head?

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hugobos
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Re: Water Temps

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There is a mandatory pressure relief valve set at 3.75barg on the coolant head tank. This puts the water temperature at max 150 deg at 3.75barg. Suppose the system is pressuring up to 3 barg the water temperature would be 143 degree Celsius. So max temperature is between 143 and 150 degrees. I do not know if lower pressures are used, but I suspect the mandatory relief valve is there because higher pressures would be beneficial.
Any technology distinguishable from magic is insufficiently advanced

Hoffman900
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Re: Water Temps

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For comparison, NASCAR limits the coolant system pressure (and has to be water), usually around 26-33psi. This puts operating temps in the 260-280* F range. NASCAR does this to influence the amount of tape the teams use on the grill.

Prior to the pressure rule, teams were running upwards of 80psi systems with coolant temp approaching 300* F.

It’s all about aero. Less you have to put through the radiator, the less in the engine bay… it’s better to manage it over and around the body.
Last edited by Hoffman900 on Tue Sep 28, 2021 9:25 pm, edited 1 time in total.

Jolle
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Re: Water Temps

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hugobos wrote:
Tue Sep 28, 2021 9:03 pm
There is a mandatory pressure relief valve set at 3.75barg on the coolant head tank. This puts the water temperature at max 150 deg at 3.75barg. Suppose the system is pressuring up to 3 barg the water temperature would be 143 degree Celsius. So max temperature is between 143 and 150 degrees. I do not know if lower pressures are used, but I suspect the mandatory relief valve is there because higher pressures would be beneficial.
A lot of these rules (as they fall into the same category as the mandated bore, stroke, V angle, etc etc) are not only that another solution might be beneficial but most of all, so that manufacturers don't have to develop all the different options and therefore save a huge amount of costs.

just imagine if there was just the rule "max 1600cc, turbo allowed and 100kg/h fuel", they would develop at least ten configurations to get an idea what is the best option.

Hoffman900
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Re: Water Temps

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It’s also a safety thing.

You don’t want a system with over a 100psi of 300* F + water rupturing. It would turn to steam instantly upon rupture (more like a bang) and be potentially fatal.

A lot of steam locomotive crew died this way.

michl420
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Re: Water Temps

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Jolle wrote:
Tue Sep 28, 2021 9:25 pm
hugobos wrote:
Tue Sep 28, 2021 9:03 pm
There is a mandatory pressure relief valve set at 3.75barg on the coolant head tank. This puts the water temperature at max 150 deg at 3.75barg. Suppose the system is pressuring up to 3 barg the water temperature would be 143 degree Celsius. So max temperature is between 143 and 150 degrees. I do not know if lower pressures are used, but I suspect the mandatory relief valve is there because higher pressures would be beneficial.
A lot of these rules (as they fall into the same category as the mandated bore, stroke, V angle, etc etc) are not only that another solution might be beneficial but most of all, so that manufacturers don't have to develop all the different options and therefore save a huge amount of costs.

just imagine if there was just the rule "max 1600cc, turbo allowed and 100kg/h fuel", they would develop at least ten configurations to get an idea what is the best option.
You are right BUT there is a cost cap now, and most of that development would be done on a computer.

Jolle
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Re: Water Temps

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michl420 wrote:
Fri Oct 01, 2021 10:33 am
Jolle wrote:
Tue Sep 28, 2021 9:25 pm
hugobos wrote:
Tue Sep 28, 2021 9:03 pm
There is a mandatory pressure relief valve set at 3.75barg on the coolant head tank. This puts the water temperature at max 150 deg at 3.75barg. Suppose the system is pressuring up to 3 barg the water temperature would be 143 degree Celsius. So max temperature is between 143 and 150 degrees. I do not know if lower pressures are used, but I suspect the mandatory relief valve is there because higher pressures would be beneficial.
A lot of these rules (as they fall into the same category as the mandated bore, stroke, V angle, etc etc) are not only that another solution might be beneficial but most of all, so that manufacturers don't have to develop all the different options and therefore save a huge amount of costs.

just imagine if there was just the rule "max 1600cc, turbo allowed and 100kg/h fuel", they would develop at least ten configurations to get an idea what is the best option.
You are right BUT there is a cost cap now, and most of that development would be done on a computer.
(At the moment) PU development isn’t part of the cost cap, plus computer simulations, although cheaper, are still bloody expensive. Another thought, we’ve seen how Mercedes found the possibilities in a quite strict PU rule book in 2014, imagine how far you can be behind if you get something structural wrong as the number of cylinders (think Yamaha vs Honda at the first year of the four stroke MotoGP)

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jjn9128
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Re: Water Temps

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There's a layout in an old racecar engineering which puts Twat from 60-72C depending on the cooler. It might be in one of the Caterham threads.
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hugobos
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Re: Water Temps

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Any technology distinguishable from magic is insufficiently advanced

J.A.W.
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Re: Water Temps

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Scootin159 wrote:
Tue Sep 28, 2021 3:54 pm
What water temps do they run in modern F1?

I was thinking about this today, and was thinking it may seem obvious, but they probably don't run the same temp range as a production vehicle. My thought process is that if a hotter radiator will see a larger temperature delta to the cooling airflow, and therefore will transfer more heat to the air. Theoretically this allow for more total cooling potential from a smaller radiator, and therefore less drag.

However, if everything was that simple, why don't see road cars with high coolant temps, and tiny radiators? There must be some drawbacks, and these are what I thought of:

1) Higher water temps, mean higher engine operating temps. That means your tolerances would need to be designed for that higher operating range. A road car needs to work at -20*, as well as at operating temp, so the lower you make that upper bound, the less range you need to cover. F1 cars on the other hand never operate below operating temp, as they pre-heat the coolant before startup.

2) Those higher operating temps will also mean you need to select materials that are stable at those temps. I know super-exotic materials like Berrylium are now banned in F1, but I still imagine they aren't using the same materials as road cars.

3) In order to go over 100*c, you need to run a pressurized system. The higher the temperature, the higher the pressures required. On a road car, a system with super critical 500* water would be a huge safety hazard. On F1, that's probably more acceptable.

4) Higher operating temps would also mean more heat transfer to the in take air through the intake manifold itself. This can probably be mitigated with heat shielding though.

5) Higher operating temps could also cause combustion issues. Wouldn't pre-detonation be more likely when your air-fuel mixture meets a hotter piston/cylinder head?
You are correct, but I'd add to your points by noting that F1 is not concerned with meeting road-traffic
emissions values, but max-efficiency in fuel burn, whereas ICE machines sold for public roads are very much compromised by the requirement to operate in the heat-range most congenial to post-combustion catalytic gas after-treament - as a priority, which is why they run via ~Lamba feedback loop - at the twin
expense of true power & fuel efficiency potentials.

F1 can manipulate the DI 'fuel bleed' via fairly sophisticated injection/ignition which is beyond the
lean-limit of regular SI road vehicle parametrics, & run really expensive fuels to boot...
"Well, we knocked the bastard off!"

Ed Hilary on being 1st to top Mt Everest,
(& 1st to do a surface traverse across Antarctica,
in good Kiwi style - riding a Massey Ferguson farm
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