Intake Cooling

[hardingfv32]

"A new article 5.6.8 of the technical regulations makes it clear that in the engine plenum air (defined officially as from plenum entry to cylinder head) temperatures must now hit a minimum target.

The rule states: "Engine plenum... air temperature must be more than ten degrees centigrade above ambient temperature. When assessing compliance, the temperature of the air will be the lap average recorded, by an FIA approved and sealed sensor located in an FIA approved location situated in the engine plenum, during every lap of the race."

IF... we assume that the FIA is responding to the possibility that one of the teams was cooling the intake charge, how would they accomplish this under the rules as we currently (2017) understand them?

Would there be a net gain in performance using something like water vapor cooling when you consider the extra weight involved? Some kind of liquid/gas refrigerant?

Brian

[J.A.W.]

Hmmm.. are there any rules specific to engine coolant heat-exchangers that forbid liquid-to-gas/pressure-release transitions?

Any 'latent heat' experiential engineers ready to give us a view as to potentially practicable applications in F1?

Glycerine has some interesting chemical properties, other than as a liquid coolant media.

[gruntguru]

I am sure there is a rule in there somewhere that forbids use of latent heat for cooling.

[bill shoe]

Some previous discussion in the Mercedes engine thread-

viewtopic.php?f=4&t=23688&p=733959#p733959

Includes speculation that fuel could be vaporized to provide intake-air cooling (fuel is the one fluid that is allowed to be used for this purpose, traditional assumption is this only occurs in combustion chamber at moment of injection, but maybe not good assumption).

Also speculation that dry-ice could be used for qualy or beginning of the race.

[e36jon]

Just as anecdotal information, the land-speed crowd is big on charge cooling. They aren't weight conscious, so there are lots of interesting fluid-to-air (intake) systems employed, often to great effect. Some are as simple as a big ice-chest in the trunk with simple plumbing through an intercooler...

I can't remember the class of cars but I also recall a case of misting the intercooler on peak demand for an extra boost in temp drop.

[stevesingo]

I remember reading that the 1988-89 Honda heated the fuel to 70degC or something.

Is there a gain to be had in air fuel mixing in cylinder by raising the fuel temp under the current regulations?

If there is, then there may be a case for using fuel in the wet side of a charge cooler to remove heat from the intake air and transfer it to the fuel.

Probably of limited use in terms of time as the fuel has no way of shedding the excess heat aside from conduction through the fuel cell walls.

Unless a fuel to air cooler is allowed.

[wuzak]

https://www.autosport.com/f1/news/13425 ... s-for-2018

Hotter air holds less oxygen than cooler air, meaning that the turbo will have to work harder, spin faster and compress more air to produce the same amount of boost than it would get if things were cooler.

Since the air is cooled after the turbo, I'm not sure how intercooling affects the turbo itself.

There can be other knock-on effects of warmer air too - it can increase the temperature inside the turbo, which causes a further loss of power, with the intercooler becoming less efficient too.

Surely with a bigger temperature difference the intercooler will be more efficient?

Does sound like the article is suggesting they are cooling the air before the compressor. Which would aid in the efficiency of the compressor. But the rule is specifically about the air after the intercooler. Not sure how you would get air to be 10°C above ambient at the intake of the compressor in any case.

[hardingfv32]

If the fuel is used for cooling does it matter that hot full is used in the cylinder injection process?

Brian

[AJI]

I remember reading that the 1988-89 Honda heated the fuel to 70degC or something.

I can't remember where I saw it, but iirc I think the reason they had to heat the fuel was due to its composition (84% toluene from memory) and to get around the fuel limit restrictions they super cooled it for extra capacity then re-heated?
I think it was only the turbo cars?
I'll try and find the source

Edit: I just found the source. It was TC on this forum. Amazing how google points you straight back to F1 technical...

viewtopic.php?t=14600

[wuzak]

I remember reading that the 1988-89 Honda heated the fuel to 70degC or something.

I can't remember where I saw it, but iirc I think the reason they had to heat the fuel was due to its composition (84% toluene from memory) and to get around the fuel limit restrictions they super cooled it for extra capacity then re-heated?
I think it was only the turbo cars?
I'll try and find the source

Edit: I just found the source. It was TC on this forum. Amazing how google points you straight back to F1 technical...

viewtopic.php?t=14600

The FIA banned the practice of cooling fuels in the 2000s. I think Ferrari was one using that trick.

[saviour stivala]

The FIA rule requiring teams to keep plenum air temperature above a minimum shows that there is/was scope for air in the plenum to be cooled in order to gain performance from the turbo engine.

[roon]

If it wasn't simply a reference to intercooling post-compressor, then we must look to expanding pressurized crankcase vapors or aerosols inside the plenum i.e. the engine sump breather. Which was mandated.

[sunitapr]

On the off chance that the fuel is utilized for cooling..Is it making a difference that hot full is utilized in the chamber infusion process?

[hurril]

I've always wondered if Mercedes aren't using the fuel to help with the cooling of their air-to-water intercooler because of the opportunities that its placement provides.

[roon]

I've always wondered if Mercedes aren't using the fuel to help with the cooling of their air-to-water intercooler because of the opportunities that its placement provides.

Might need a way to cool the fuel back down. By what means?