2021 Engine thread

[Cold Fussion]

The 140kg would be a limit, you dont have to run that as a mixture

But why specify a limit that is practically unattainable? Why is an engine airbox design arms race more interesting to anyone than an engine design arms race?

[Holm86]

It doesn't just work like that, you can't just set a rpm limit and a fuel flow limit on a naturally aspirated engine.
First of all the current formula works because you can both control airflow and fuel flow very precisely. You can't control airflow very precisely on a naturally aspirated engine.

Didn't they do precisely that from 2008-2013?

The formula you created there would be way too rich in AFR.
A 2 liter engine at 14.000 rpm consumes 14.000 liters of air per minute, at volumetric efficiency of 100%.
14.000 liters of air weighs about 18.1 kilogrammes at atmospheric pressure.
140kg/h of fuel = 140/60 = 2.33kg/min

It's harder to run excessively lean without forced induction.

So the air fuel ratio would be 18.1kg of air divided by 2.33kg of fuel which equals 7.8 and that's too rich.
And remember that the volumetric efficiency and air density are variables, variables you can offset by using a turbo, but not in a NA engine.

You're still limited by the fuel supply, so you can turn up the power but you won't make it to the end, unless of course the teams develop the heads and increase efficiency.

No, there was no fuel flow limit from 2008 to 2013, they could burn unlimited amounts of fuel, which is why they had to impose a rpm limit, because on a NA engine the only way to burn more fuel is to increase RPM go get enough air

And no, you wouldnt be limited by the fuel supply but the air supply at 14K rpm with 140kg/h of fuel.
You would never be able to burn those 140kg/h optimally

[Holm86]

The 140kg would be a limit, you dont have to run that as a mixture

But why specify a limit that is practically unattainable? Why is an engine airbox design arms race more interesting to anyone than an engine design arms race?

Exactly

[johnny comelately]

The 140kg would be a limit, you dont have to run that as a mixture

But why specify a limit that is practically unattainable? Why is an engine airbox design arms race more interesting to anyone than an engine design arms race?

Exactly

My aplogies, I did not see the NA in the original post. my assumptions were on turbo

[godlameroso]

It doesn't just work like that, you can't just set a rpm limit and a fuel flow limit on a naturally aspirated engine.
First of all the current formula works because you can both control airflow and fuel flow very precisely. You can't control airflow very precisely on a naturally aspirated engine.

Didn't they do precisely that from 2008-2013?

The formula you created there would be way too rich in AFR.
A 2 liter engine at 14.000 rpm consumes 14.000 liters of air per minute, at volumetric efficiency of 100%.
14.000 liters of air weighs about 18.1 kilogrammes at atmospheric pressure.
140kg/h of fuel = 140/60 = 2.33kg/min

It's harder to run excessively lean without forced induction.

So the air fuel ratio would be 18.1kg of air divided by 2.33kg of fuel which equals 7.8 and that's too rich.
And remember that the volumetric efficiency and air density are variables, variables you can offset by using a turbo, but not in a NA engine.

You're still limited by the fuel supply, so you can turn up the power but you won't make it to the end, unless of course the teams develop the heads and increase efficiency.

No, there was no fuel flow limit from 2008 to 2013, they could burn unlimited amounts of fuel, which is why they had to impose a rpm limit, because on a NA engine the only way to burn more fuel is to increase RPM go get enough air

And no, you wouldnt be limited by the fuel supply but the air supply at 14K rpm with 140kg/h of fuel.
You would never be able to burn those 140kg/h optimally

What air fuel ratios do you tune for in NA cars? I go for 11.7-12.2, some high strung NA cars I'll go as rich as 10.8.

But yeah 140kg flow rate is probably too much, sorry to have triggered you with a 20kg/hr overestimation.

[johnny comelately]

Didn't they do precisely that from 2008-2013?



It's harder to run excessively lean without forced induction.



You're still limited by the fuel supply, so you can turn up the power but you won't make it to the end, unless of course the teams develop the heads and increase efficiency.

No, there was no fuel flow limit from 2008 to 2013, they could burn unlimited amounts of fuel, which is why they had to impose a rpm limit, because on a NA engine the only way to burn more fuel is to increase RPM go get enough air

And no, you wouldnt be limited by the fuel supply but the air supply at 14K rpm with 140kg/h of fuel.
You would never be able to burn those 140kg/h optimally

What air fuel ratios do you tune for in NA cars? I go for 11.7-12.2, some high strung NA cars I'll go as rich as 10.8.

But yeah 140kg flow rate is probably too much, sorry to have triggered you with a 20kg/hr overestimation.

On some low strung (Harleys) you can aim at 12's in the right part of the map, but thats because....
I suspect that if we knew the true calibration of O2 sensors we would get a shock.

[godlameroso]

No, there was no fuel flow limit from 2008 to 2013, they could burn unlimited amounts of fuel, which is why they had to impose a rpm limit, because on a NA engine the only way to burn more fuel is to increase RPM go get enough air

And no, you wouldnt be limited by the fuel supply but the air supply at 14K rpm with 140kg/h of fuel.
You would never be able to burn those 140kg/h optimally

What air fuel ratios do you tune for in NA cars? I go for 11.7-12.2, some high strung NA cars I'll go as rich as 10.8.

But yeah 140kg flow rate is probably too much, sorry to have triggered you with a 20kg/hr overestimation.

On some low strung (Harleys) you can aim at 12's in the right part of the map, but thats because....
I suspect that if we knew the true calibration of O2 sensors we would get a shock.

I only tune with wideband 02, if my customers don't have one I tell them to get one and get back to me.

[gruntguru]

The AFR you get from a wideband O2 sensor is not the AFR seen in the combustion chamber. Exhaust composition includes scavenged mixture which will be richer than average in some engines and leaner than average in others (including DI systems like F1)

[johnny comelately]

and the roughly 3% unburnts

[godlameroso]

The AFR you get from a wideband O2 sensor is not the AFR seen in the combustion chamber. Exhaust composition includes scavenged mixture which will be richer than average in some engines and leaner than average in others (including DI systems like F1)

Close enough for the $6,000 turbo kits I usually tune. The unlimited budget folks can afford better sensors, those folks are by far the minority.

[johnny comelately]

The AFR you get from a wideband O2 sensor is not the AFR seen in the combustion chamber. Exhaust composition includes scavenged mixture which will be richer than average in some engines and leaner than average in others (including DI systems like F1)

Close enough for the $6,000 turbo kits I usually tune. The unlimited budget folks can afford better sensors, those folks are by far the minority.

in the end you go for power or rideability/ driveability anyway, its just important to be aware of what is happening in the background particularly when designing the better mousetrap

[1158]

So...

MGU-H to be dropped

The FIA also presented the latest version of its 2021 power unit regulations, noting only that the engine would be a 1.6-litre V6 turbo hybrid, with no MGU-H. This format was first outlined, with much more detail, on October 31 last year.

Although the decision to abandon the MGU-H shows that Liberty has not compromised on its stance about the energy recovery system, other elements of the 2021 package remain the subject of debate.

Sources have indicated that the FIA and Liberty have different views on some aspects of the final concept.

The FIA said that its Technical Department “will now meet with current and potential power unit manufacturers to discuss in more detail, with a view to concluding the 2021 regulations by the end of May.”

https://www.motorsport.com/f1/news/f1-r ... s-1027456/

If they are going to dump the MGU-H I'd like to see them go with unlimited energy recovery from the turbo (just a GU-H) with a much stronger MGU-K setup. Keep the total horsepower about the same.

I know F1 isn't about standardization but I think (if they want more engine suppliers) they would need to do a standard hybrid setup. Not ideal, but a way to help control costs and entice more suppliers.

As far as turbo setups I have always used cheap, fast, and reliable. You get to Pick 2. As my rule of thumb. I went fast and reliable.

[NL_Fer]

The longer i think of it, the more i am convinced that the 4 current manufacturers will not run without a some form of exhaust heat recovery. Most part of developed technology around lean-combustion will become useless if you cannot recover it from the exhaust.

Even Honda seems to got it sorted, they are not going to dump it after 2 years.

[AJI]

The longer i think of it, the more i am convinced that the 4 current manufacturers will not run without a some form of exhaust heat recovery. Most part of developed technology around lean-combustion will become useless if you cannot recover it from the exhaust.

Even Honda seems to got it sorted, they are not going to dump it after 2 years.

Let's hope they keep it. The knock on effect of dropping the H is enormous.
'Cost savings!', they cry. How changing platforms a year after everyone has perfected the current unit can cut costs is beyond me..?
They should freeze the ICE and open up the ERS a bit more. Perhaps a larger K and 8MJ deployment?

[Tommy Cookers]

petrol-electric it is then !! - with a 1600cc 'range-extender'