F1technical.net

SameSame wrote:

GhostF1 wrote:

SameSame wrote: Thank you for a very logical explanation.

Why does Hasagawa so often say that introducing a better combustion concept reduces harvesting?

In very basic terms. The turbo is driven by waste energy from combustion. But if the engine has become extremely efficient and harnasses more of that energy, there is less "waste" available to drive the turbo and therefore the MGU-H in which it is attached. So Honda are now forced to be clever and find other areas to claw more energy back to drive the turbo/MGU-H (Merc's Vortex Exhaust being one solution).

At least that's my understanding of it.

From what I understand of what Tommy Cookers said; the combustion efficiency is the same (TJI needed to keep the combustion efficiency the same) it is more the heat dilution that changes (less waste heat to coolant, what about sensible heat though?). And more turbine power is available due to higher mass flow rate of mixture but more compressor power needed to achieve lean mixture so net effect is zero?

I'm probably entirely wrong here, but I was under the impression that Hasegawa had been implying, pretty much most of last year, that any improvement in combustion would directly affect the energy of the exhaust gas. So I would probably of said the potential energy of the exhaust would be lower with an improved concept, therefore negatively impacting the turbines potential. This also goes back to the theory from last year that Honda had an engine mode that deliberately ran it in such a way that it created a denser combustion product (gas) that drove the turbo harder which allowed the MGU-H to increase harvesting potential. This also stemmed from some comments Hasegawa made, probably around Canada when the new turbo was introduced which he was quoted as saying "was required to claw back turbine efficiency after the combustion was improved".

godlameroso wrote:It's strange, when an air fuel mixture is ignited, the reaction actually loses some mass, which is converted to energy. So this reduced mass is creating energy by increasing its volume. Kind of counter productive don't you think? Makes having a turbo all the more sense when you think of it like that. What better way to compensate for the lost mass than by adding more mass?

Each combustion event releases about 2500J and total combustion mass is about 0.00012 kg.

E=mC^2 so mass lost m = E/C^2 = 1200J/(3E8)^2 = 1.3E-14 kg.
As a fraction of total mass in the combustion chamber this is 1.1E-14/0.00012 = 9.1E-11 or 0.0000000091%

The boost required to make up for the lost mass could be provided by a butterfly flapping its wings. Probably not legal though.

kasio wrote:

PlatinumZealot wrote:

godlameroso wrote:It's strange, when an air fuel mixture is ignited, the reaction actually loses some mass, which is converted to energy. So this reduced mass is creating energy by increasing its volume. Kind of counter productive don't you think? Makes having a turbo all the more sense when you think of it like that. What better way to compensate for the lost mass than by adding more mass?

Do not twist it too much. The reaction loses reactants. From a classical physics or engineering point of view no mass is lost in the control volume. The energy comes from chemical bonds in the hydrocarbon. Not nuclear mass loss as you are suggesting.

IMHO change of weight is due to micro particles which are emitted in nuclear deacy. (nuclear reaction). so in general mass of products is still same as mass or reagents.

Yes.. That is correct. Same thing i am saying. However the mass of reactants reduces as the reaction goes on. This is elementary.

Gentle people of F1 technical.

There is a graph that honda relased showing the superimposition of:

ICE power, and
MUGH regeneration

There is a point beyond where the ICE power is too high you will take too much energy via the compressor to feed the MGUH.

There is a nother point where the MGUH delivery to the MGUK is so high that it will cause higher back pressure in the turbine and also take enery from the compressor thus lowering boost and engine power.

The more efficient your ICE is means less heat loss and the less energy you have going to the exhaust gasses and the MGUH.

This is a good thing!

Becuase ICE energy is of a higher quality than the energy in the exhaust pipe and it directly goes to the crankshaft.

The MGUH will have less energy to harvest that is true. However because of the stronger ICE you will use less battery assist overall and also your fuel efficiency will be better too. Look at Mercedes for example. This is the direction to go in.

Well, that and the more efficient ICE tends to loose less heat to the cooling system as well as the exhaust, which means a net gain. And smaller sidepods with less cooling drag.

That and you have an unregulated engine lubricant concoction assisting combustion.

Some say.......they are filming whut AUS spec......

I would love a source for that.

Thunders wrote:I would love a source for that.

Near track observers and listeners

GoranF1 wrote:

Thunders wrote:I would love a source for that.

Near track observers and listeners

https://twitter.com/HondaRacingF1/statu ... 7367238657

It's today

I don't think there is a seperate oil combustion in the Honda engine. There is no evidence showing that and a seperate system wouldn't help because of the space problem.

Regarding the lower harvesting potential, I didn't read all posts here but I can help you with that:

The amont of air going through the turbine is only depending on engine speed, volumetric effiency (also controlled by throttle) and the Lambda. During combustion, no mass is lost or added by any reaction, this is simply impossible and will never be possible.

Calculation is like that:
MASSair = (displacement) * (engine speed) * (absolute boost pressure) * (normal air density) / 2
MASSgasoline = (MASSair) / (AF-ratio)
MASSturbine = MASSair + MASSgasoline

While having a more leaner combustion will give you a higher mass output at the turbine , you won't gain any harvesting potential. Yes, the power is higher, but you have to remember that the compressor size also has to increase and with that the power losses into the compressor.

Also, a higher ratio than needed will only give you a bigger turbine and compressor which isn't good for compactness at all, no matter where they are positioned. Since the efficiency is never at a maximum, both on compressor and turbine side, you want to keep these things not unneccesarily big.

Also remember: increasing the pressure of the exhaust gases with leaner combustion doesn't have any positive effect besides mostly compensating the bigger power losses of the compressor. Just remember: The amount of heating transfering to the air in the chamber will always be the same. if you just have more air, the air in the chamber won't heat up as much as before.

Now to the part of the harvesting. The potential is bigger on a normal combustion engine because of the slower combustion. This way, the time to transfer energy to the cylinder walls and not into the gas is lower and you have more pressure because the combustion isn't running as fast as before, therefor cooling of later.

When using something like TJI, you have a effect that is very much comparable to HCCI combustion. The pressure in the cylinder rises dramatically faster than before becuase combustion is finished much earlier. Now, you have a longer time with hot gases wanting to expand and loose their energy in the cylinder than before and the transfer of heat to the walls happens more intensively, thus the energy efficiency of the ICE gets much higher, while the energy that is left in the exhaust gases get's lower.

I hope you all could understand that

well, my guess is that .......
combustion gets slower with leaner mixtures (and combustion slowing and combustion becoming less efficient go hand-in-hand)
combustion speed is good with traditional race mixture strength (or the 20000 rpm big bore NA engines were losing potential power)

ie TJI or similar devices are used to speed the combustion of very lean mixtures to about that level
(and another poster has said they may alleviate a detonation issue by having less end gas)


@ glenn .....
regarding your recent post on even-firing etc .....
that one bank has a longer exhaust length port-to-turbo than the other so that the exhaust pulses are evenly spaced at the turbo .....
I take as agreement with my (exhaust length differential) view posted over years and lately (dual inlet or not/ 6 even pulses or 3 double pulses/cycle) ....

is this preservation and use of pulses compatible with your exhaust (ring) vortices post/your other type vortices post ?

ie I assume currently there's NA-style exhaust pulse 'extractor' effect by 'negative' pulses 'reflected' back into the cylinders at overlap
these pulse 'reflections' coming both from the header-header-runner junction and the runner-turbo housing junction

this is powerful 'free supercharging' - ie increasing turbine recovery by reducing the work needed from the compressor
and it is more beneficial to recovery at the higher boost/exhaust pressures of increasingly lean mixtures

this seems a crucial area for some research and progress ?

Tommy Cookers wrote:well, my guess is that .......
combustion gets slower with leaner mixtures (and combustion slowing and combustion becoming less efficient go hand-in-hand)
combustion speed is good with traditional race mixture strength (or the 20000 rpm big bore NA engines were losing potential power)

ie TJI or similar devices are used to speed the combustion of very lean mixtures to about that level
(and another poster has said they may alleviate a detonation issue by having less end gas)


@ glenn .....
regarding your recent post on even-firing etc .....
that one bank has a longer exhaust length port-to-turbo than the other so that the exhaust pulses are evenly spaced at the turbo .....
I take as agreement with my (exhaust length differential) view posted over years and lately (dual inlet or not/ 6 even pulses or 3 double pulses/cycle) ....

is this preservation and use of pulses compatible with your exhaust (ring) vortices post/your other type vortices post ?

ie I assume currently there's NA-style exhaust pulse 'extractor' effect by 'negative' pulses 'reflected' back into the cylinders at overlap
these pulse 'reflections' coming both from the header-header-runner junction and the runner-turbo housing junction

this is powerful 'free supercharging' - ie increasing turbine recovery by reducing the work needed from the compressor
and it is more beneficial to recovery at the higher boost/exhaust pressures of increasingly lean mixtures

this seems a crucial area for some research and progress ?

I don't understand you completely I think but in regards to the Vortex System, I do think that it should be possible with a more odd-firing system. I only did stationary simulations until now (had no time because I wanted to work at my own engine again ) but it seems like these trapped low-velocity air volumes should be stable even with back pulses because of the shape of these minichambers which blocks any travel of air to these pockets.

In terms of pulse charging by hitting the right pipe length with the right rpm, this should also work, but the effect would be lower on pressure charged systems. With odd-firing and one big pulse travelling to the turbine, this evect could be further dampened, or (what I don't really know) even more intesified, which could be possible since surface area will stay the same throughout the manifold.

http://www.autosport.com/news/report.ph ... er-failure