Reactions following injection of water M4 BMW ...

Water injection in thermal engines and the famous "pantone engine". General informations. Press clippings and videos. Understanding and scientific explanations on the injection of water into engines: ideas for assemblies, studies, physico-chemical analyzes.
Janic
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Re: Reactions following the BMW M4 water injection ...




by Janic » 09/05/17, 08:29

one does not prevent the other, it's just a technical question and therefore experimentation and mastery of the process and Audi as BMW are in their infancy (reminder Renault had used it in F1 memory!) However, these injections have little connection with the Gillier Pantone system which remains the simplest system and within the reach of any handyman.
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Re: Reactions following the BMW M4 water injection ...




by izentrop » 06/10/17, 23:22

Tests of the BMW M4 GTS 2016 by motor legend. http://www.motorlegend.com/essai-voitur ... 19355.html
A motor more talkative than ever

This is the same block as the normal M4, with direct injection, two turbos, Valvetronic variable valve lift or double Vanos. But it also receives a new system of cooling by water spray in the intake manifolds. This lowers the temperature of the air admitted into the cylinders by about 25 ° C, allowing a substantial increase in compression rate without the risk of knocking. Suddenly, the power jumps from 431 to 500 ch, while the torque reaches the 600 Nm. Forced, performance progresses: the 0 100 km / h is performed in 3,8 s (4,1 for the normal M4),


There is no question of fuel economy, given the price of the model, it is the least of the worries of the buyer. Moreover it is logical that a power gain is accompanied by an increase in consumption and not the other way around.

For the M4 GTS 2017, even discusses BMW:
The technology of motor racing on the road: the BMW M4 GTS is equipped with an innovative system of water injection, which has been proven on the BMW M4 commissioned as a Moto GP's Safety Car by boosting its power and his couple. This system is to spray a mist of water into the intake manifold of the intake module. The vaporization of water significantly cools the intake air, and consequently the final compression temperature in the combustion chamber, thus decreasing the rattling tendency. This feature allows the 6 gasoline engine M TwinPower Turbo in-line cylinders to be used with increased boost pressure and an early ignition point. Power and torque increase as thermal stresses decrease. http://www.bmw.fr/fr/new-vehicles/M/m4- ... 4-gts.html
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Re: Reactions following the BMW M4 water injection ...




by Remundo » 07/10/17, 10:35

it's a basic analysis, everyone knows that supercharged engines like cold air; but no word on the changes in combustion caused by the presence of water before ignition.

I always had the intuition that the presence of water H2O before and at the very beginning the combustion created fragments (free radicals H * * OH, various ions) which accelerated the dismantling of the carbon chains; said in simpler, more complete combustion, faster, less unburned.

for that, you don't need a lot of water, a vaguely distributed "fog" is enough. Too much water will have harmful effects, going as far as preventing inflammation. There is therefore an optimum to be found.
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Re: Reactions following the BMW M4 water injection ...




by Christophe » 07/10/17, 13:54

In agreement with Remundo, the effect of water injection is not limited to a cooling of the intake gases!

We could also cite the reaction of "hot carbon" which begins at 800 ° C:

C + H2O -> CO2 + H2

C + H2O -> CO + H2

It explains easily why a water injection engine emits less soot (fine and less fine particles ...)

Then the sprayed water has a relaxing effect: a droplet which vaporizes at 100 ° C gains 400 times its droplet volume ... the effect is certainly not negligible on the SME ... And before 100 ° C it contributes to increase the compression ratio: the water is not compression (in "basic" physics)

BMW engineers (and others) know all this very well (and if they do not know it is that they are sacred spots!) : Cheesy:
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Re: Reactions following the BMW M4 water injection ...




by izentrop » 07/10/17, 15:22

JEAN-LUC MOREAU keeps repeating in his review http://www.auto-moto.com/actualite/envi ... 43967.html
But it is the only one to proclaim it. In the other magazines auto (serious) one speaks only gain in power.

The system sold by breton touted in another subject is based on the redox magnesium and assert an average saving of 20 to 25% fuel. https://www.eco-leau.com/le-kit-hybride4all/

Why do not we find real engine tests with or without a test bench? (with real scientific protocol)
This is good because there is no gain on an already optimized engine.

Not to mention that sending water into the intake may create oxidation and mix with the oil to make mayonnaise. : Twisted:
In the BMW case, the injection is made only in case of extreme solicitation, so just a commercial argument.

Apparently, the real magnesium engine has not given away https://fr.wikipedia.org/wiki/Moteur_au_magn%C3%A9sium
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Re: Reactions following the BMW M4 water injection ...




by Remundo » 07/10/17, 17:00

Christophe wrote:In agreement with Remundo, the effect of water injection is not limited to a cooling of the intake gases!

We could also cite the reaction of "hot carbon" which begins at 800 ° C:

C + H2O -> CO2 + H2

I think it's more like CO + H2

otherwise, on a healthy engine, no "mayonnaise" that holds up ... combustion produces water, even when there is no water injection.
BMW engineers (and others) know all this very well (and if they do not know it is that they are sacred spots!) : Cheesy:

What is interesting is the hardening of anti-pollution standards that brings them on it. Apparently it allows to have less costly and energy-efficient depollution systems by throttling the exhaust system (like FAP, Adblue and all kinds of gas plants ...)
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Re: Reactions following the BMW M4 water injection ...




by Christophe » 07/10/17, 18:43

Oops forgiveness yes CO ... not well awake ... the night was long ...

But the CO will rebrul quite quickly as the H2 to form CO2 and H2O ...

CO is the main "fuel" of lean gas in gasifiers ...
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Re: Reactions following the BMW M4 water injection ...




by Christophe » 07/10/17, 18:47

izentrop wrote:JEAN-LUC MOREAU keeps repeating in his review http://www.auto-moto.com/actualite/envi ... 43967.html
But it is the only one to proclaim it. In the other magazines auto (serious) one speaks only gain in power.


Good article, but where is the video?
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Re: Reactions following the BMW M4 water injection ...




by Christophe » 07/10/17, 18:56

izentrop wrote:Not to mention that sending water into the intake may create oxidation and mix with the oil to make mayonnaise. : Twisted:


We have never seen an engine break down faster when it was running in fog or mist ... but an engine that does not run for a long time does not like storage in too much humidity ... of course. ..
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