2014 intercooling

[Ferraripilot]

A mini intercooler just behind the driver's head or between the fuel tank partially in the path of the intake flow could make sense. Coolant from the traditional radiator system could be shared with the liquid to air intercooler perhaps with all coolant filter in through the intercooler first prior to entering the engine.

I just cannot forsee these massive air to air units we've seen conjectured in early renderings taking up an entire sidepod making sense. One sidepod for an intercooler, and the other for a traditional radiator? I can't see it.

[Pierce89]

You can't have a fuel limited racing series and then have a turbo charged engine without an intercooler.
The intercooler directly affects the fuel efficiency of the engine. I think we had this discussion in the engine thread.

Right you are. I was only making it clear, that on low boost systems, there's not much difficulty in running without an intercooler, because someone claimed it was very difficult to run a turbo without an intercooler.

[RicerDude]

A mini intercooler just behind the driver's head or between the fuel tank partially in the path of the intake flow could make sense. Coolant from the traditional radiator system could be shared with the liquid to air intercooler perhaps with all coolant filter in through the intercooler first prior to entering the engine.

I just cannot forsee these massive air to air units we've seen conjectured in early renderings taking up an entire sidepod making sense. One sidepod for an intercooler, and the other for a traditional radiator? I can't see it.

An intercooler, even a really small one would still most likely be wider than the turbo air inlet required for next year so it will just be disturbing airflow to the rear wing. And seeing as rear down force wont be in abundance next year I find this solution highly unlikely.

[Ferraripilot]

An intercooler, even a really small one would still most likely be wider than the turbo air inlet required for next year so it will just be disturbing airflow to the rear wing. And seeing as rear down force wont be in abundance next year I find this solution highly unlikely.

The intercooler would be mounted internally within the body work either above the fuel tank, just behind it, or just behind the driver's head. It won't be at all visible or alter bodywork in that area as we know it to be.


The beauty of a liquid to air intercooler is they can be designed in many different ways.

[timbo]

Here's paper on intercoolers in gas turbine (Brayton Cycle) it actually says intercoolers hurt thermal efficiency:
http://web.me.unr.edu/me372/Spring2001/ ... ration.pdf

[wuzak]

Here's paper on intercoolers in gas turbine (Brayton Cycle) it actually says intercoolers hurt thermal efficiency:
http://web.me.unr.edu/me372/Spring2001/ ... ration.pdf

Yes, that is true. But it is slightly different with piston engines (otto cycle), since the extra heat can cause problems for combustion.

[timbo]

Here's paper on intercoolers in gas turbine (Brayton Cycle) it actually says intercoolers hurt thermal efficiency:
http://web.me.unr.edu/me372/Spring2001/ ... ration.pdf

Yes, that is true. But it is slightly different with piston engines (otto cycle), since the extra heat can cause problems for combustion.

Agreed, but without the limit of ON in fuel, and high pressure multi-phase injection is it a problem that can be solved I wonder?

[ringo]

Here's paper on intercoolers in gas turbine (Brayton Cycle) it actually says intercoolers hurt thermal efficiency:
http://web.me.unr.edu/me372/Spring2001/ ... ration.pdf

Not exactly. Depends on where the intercooler is placed.
It's not black and white. The compression work is reduced, not the thermal efficiency.
It can be shown thermodynamically why intercooling between compression stages increase efficiency.

You have interpreted the documented incorrectly.

[wuzak]

Here's paper on intercoolers in gas turbine (Brayton Cycle) it actually says intercoolers hurt thermal efficiency:
http://web.me.unr.edu/me372/Spring2001/ ... ration.pdf

Not exactly. Depends on where the intercooler is placed.
It's not black and white. The compression work is reduced, not the thermal efficiency.
It can be shown thermodynamically why intercooling between compression stages increase efficiency.

You have interpreted the documented incorrectly.

The intercooler reduces the temperature of the air exiting the compressor and entering the combustion chambers. That means lower temperature on the entry to the turbine, which means lower thermal efficiency.

This can be recovered by using reheat - burning a little more fuel in the exhaust and running it through a second turbine.

And/Or regeneration. Regeneration is taking the waste heat from the exhaust and using it to increase the air temperature after the compressor. This results in higher temperatures at the turbine or less fuel required to reach the same temperature.

Intercooling between compressor sets (high and low pressure, rather than every individual stage) does lower the compressor work required, but does not increase the overall efficiency of the turbine.

It is also irrelevent for most reciprocating turbo engines. Intercooling in turbo engines really is aftercoling, since in most cases there is only one stage of compression. It is added to keep the intake air at a temperature that won't induce detonation in the engine.

[wuzak]

Here's paper on intercoolers in gas turbine (Brayton Cycle) it actually says intercoolers hurt thermal efficiency:
http://web.me.unr.edu/me372/Spring2001/ ... ration.pdf

Not exactly. Depends on where the intercooler is placed.
It's not black and white. The compression work is reduced, not the thermal efficiency.
It can be shown thermodynamically why intercooling between compression stages increase efficiency.

You have interpreted the documented incorrectly.

The intercooler reduces the temperature of the air exiting the compressor and entering the combustion chambers. That means lower temperature on the entry to the turbine, which means lower thermal efficiency.

This can be recovered by using reheat - burning a little more fuel in the exhaust and running it through a second turbine.

And/Or regeneration. Regeneration is taking the waste heat from the exhaust and using it to increase the air temperature after the compressor. This results in higher temperatures at the turbine or less fuel required to reach the same temperature.

Intercooling between compressor sets (high and low pressure, rather than every individual stage) does lower the compressor work required, but does not increase the overall efficiency of the turbine.

It is also irrelevent for most reciprocating turbo engines. Intercooling in turbo engines really is aftercoling, since in most cases there is only one stage of compression. It is added to keep the intake air at a temperature that won't induce detonation in the engine.

[ringo]

The intercooler reduces the temperature of the air exiting the compressor and entering the combustion chambers. That means lower temperature on the entry to the turbine, which means lower thermal efficiency.

No an intercooler is not before a turbine. It is always between compression stages.

This can be recovered by using reheat - burning a little more fuel in the exhaust and running it through a second turbine.

Nope. I've done some turbo machinery theory many years ago, reheat is not for recovery. It's simply to raise the pre combustion temperatures. You can still use reheat on a system with no intercooler.

And/Or regeneration. Regeneration is taking the waste heat from the exhaust and using it to increase the air temperature after the compressor. This results in higher temperatures at the turbine or less fuel required to reach the same temperature.

What higher temperature does is reduce the amount of heat needed to be added by the fuel.

Intercooling between compressor sets (high and low pressure, rather than every individual stage) does lower the compressor work required, but does not increase the overall efficiency of the turbine.

You are trying to back out of the discussion now by muddling the discussion. Why are talking about efficiency of the turbine, when you were orginally talking about thermal efficiency?
The turbine efficency is fixed.

It is also irrelevent for most reciprocating turbo engines. Intercooling in turbo engines really is aftercoling, since in most cases there is only one stage of compression. It is added to keep the intake air at a temperature that won't induce detonation in the engine.

Let me reveal a secret to you.

first stage of compression: compressor (compressing air right?)

second stage of compression: piston (still compressing air correct?)

You know what i'm going to do to increase the efficiency? I'm going to put an intercooler between those 2 stages of compression on that piston engine, so that the pistons have more mass of air to compress.


There are 2 stages of compression in all turbo charged piston engines. I hope this clears things up for you.

[Moxie]

If you read my introduction you will see that I know just enough thermodynamics to really make a mess of things, so forgive me it this comes across as utter nonsense.

Furthermore, I get basic concepts like the Venturi effect, and the Coanda effect, and laminar flow, but I dare not suggest that I really know much about aerodynamics. Again, I find myself intimidated by the level of knowledge here...go easy on me if I make a mess of things.

It seems to me that since aerodynamics is affected by pressure and temperature, that it would behoove the engineers to use waste temperature to benefit air flow. Clearly the blown exhaust is out. But as the air around the car is the ultimate heat sink why would the engineers not place heat exchangers where they can positively affect air flow. In the 1970's Ferrari experimented with heat exchanger plates, unfortunately they were not efficient enough to cool the engine, and they returned to the use of traditional radiators. But consider this: using an inefficient hot plate where it can be of benefit may reduce the load on the traditional heat exchanger that is catching wind elsewhere, thereby allowing its drag to be reduced.

Watch out: here is where I may really screw it up: I know you all will correct me If I am wrong.

If I remember correctly adding temperature to the airflow upstream of the venturi constriction would increase mass airflow, thus lower the pressure in the constriction, i.e. more downforce.

Ok, so to tie it in with the point of this topic. At least one heat exchanger in an intercooler system could be a plate exchanger that sheds heat to the underbody.

Have your way with me...I'm ready for it.

[rjsa]

Here's paper on intercoolers in gas turbine (Brayton Cycle) it actually says intercoolers hurt thermal efficiency:
http://web.me.unr.edu/me372/Spring2001/ ... ration.pdf

Not exactly. Depends on where the intercooler is placed.
It's not black and white. The compression work is reduced, not the thermal efficiency.
It can be shown thermodynamically why intercooling between compression stages increase efficiency.

You have interpreted the documented incorrectly.

The intercooler reduces the temperature of the air exiting the compressor and entering the combustion chambers. That means lower temperature on the entry to the turbine, which means lower thermal efficiency.

This is so wrong. Compressing cooler air requires less work, just get back to your TD text books, you've got your channels crossed - time for a concept review.

[riff_raff]

There are trade-offs with intercooling. The intercooler adds weight, it creates intake airflow losses, and with low boost levels the size of the intercooler core required to achieve any appreciable drop in charge temperature can be quite significant.

An intercooler reduces the temperature of the air discharged from the turbo compressor, and it increases the density of the intake air charge, but it also reduces the pressure of the air charge at the intake valves.

[ringo]

I think that will be the major issue with an unconventional design with increased surface area for the heat exchangers.

What interests me though is what temperature will the teams want the intercooled air to be?

What determines the temperature that they will settle at for their engines. Or do they build as big an intercooler as possible and whatever intercooled temperature they get they work with.
Keeping in mind that they are free to play with pressure ratio, compression ratio, and intake temperatures.
What decides the design temperature?