Water-Diesel Mix: Opinions and Reviews

Hello!

Just now, there was a report from a researcher in Cologne who wants to dilute diesel with water.

Here's a link I found about it:

http://www.rp-online.de/public/article/nachrichten/wissenschaft/technik/52658

What do you think about it?



Best regards,
MisterX.

Ja ist klar. Ich strecke den Diesel mit 50% Wasser und mein AUto verbraucht weniger. So far, so good.
Let's think about where the propulsion, or kinetic energy, comes from. Perhaps it's because fuel is burned, converting thermal energy into kinetic energy. So, if I only burn half the fuel, I would only have half the propulsion. I think that's a very simplistic calculation. Also, I'd like to see a gasoline engine that runs without any problems with a 50% water content.

Hi,

An interesting thing that has already been tried with gasoline engines.
A few years ago, I heard about an American who, using an emulsifier, created a mixture of 55% water and 45% gasoline. The test vehicles ran perfectly with this mixture, without significant loss of performance.
I don't know what became of it. It's likely that the oil industry bought the patents and simply shelved them.

The same principle likely works with diesel fuel. However, I imagine there might be issues with the lubricity of such mixtures, which could necessitate special additives to ensure that the ESPs (likely referring to Exhaust Gas Recirculation systems) can withstand them.

I would also use such a blend to refuel my diesel vehicle at today's diesel prices, provided it doesn't cause any significant drawbacks. The primary goal must be climate protection. Perhaps something like this could also be offered at a lower price, but that will likely only be possible when a real market for it exists.

So, we'll just have to wait and see. Hopefully, the story is true and it really will become an alternative. The public interest then just needs to be great enough that politicians take notice and introduce it...

Greetings.

Eike.

Hmm, would it be possible to mix it yourself? Like, taking only half of the fuel from the gas station, adding an additive, and then putting tap water into the tank? What about rust?

hmm, and would it be conceivable that one could perhaps mix it themselves? So, taking only half of it at the gas station, adding an additive, and letting the good old tap water run into the tank? What about rust?

Hi,
Tap water is probably not suitable because, depending on the region, it contains a relatively high amount of lime, which remains as dust during combustion and then exhibits an abrasive effect. Moreover, in newer vehicles, this could likely clog the particulate filters.
So, it will probably be distilled water. Another question is how the juice will behave in the winter. But it's also possible that it will only be offered during the warmer seasons.
Greetings.

Eike.

Hi,
Buy me a used Kärcher from iih-Bäh! soon, and then I'll drive around with clean water!

What is all this supposed to mean?
Besides the fact that the injection timing can probably be advanced slightly due to the cooling effect and resulting reduction in NOx emissions, there isn't much else that can be saved. It sounds like a perpetual motion machine.

To even think of such things...

I have some really great pictures of fuel injection systems that only received a few percent water in the diesel.

That's where the rust blooms...

cheerful Bosch-sponsored...

CU Gremlin.

matthiasTDI96 wrote:

Let's consider where the propulsion, i.e., the kinetic energy, comes from? Perhaps it's because fuel is burned, converting thermal energy into kinetic energy. So, if I only burn half the fuel, I would only have half the propulsion. I think this is a very simplistic calculation.

The engine, based on a rough estimate, only transfers about 1/3 of the combustion energy to the crankshaft. The rest is lost as heat in the coolant and exhaust. If a portion of this heat were used to evaporate water, thereby generating additional pressure, the efficiency could be improved. On the other hand, heat is extracted from the expanding hot gas during the power stroke, which in turn reduces the pressure. It's necessary to calculate and see what the actual net result would be. However, achieving the same power output with 50% water seems utopian to me. That would represent a peak efficiency of 85%. That would completely revolutionize fuel cell vehicles.

In terms of efficiency, I think it's a very simplistic calculation because water has a very high specific heat of vaporization, and therefore removes a lot of heat from the surroundings when it evaporates.

In terms of performance, there's no question: if the resulting calorific value of the fuel decreases, the maximum achievable engine power also decreases. Therefore, in my opinion, it would be sensible to operate the engine with the emulsion – if at all – only in the partial load range, in order to maintain its maximum performance and, consequently, its power-to-weight ratio.

Regarding the issue of the EGR system, a slight increase in efficiency might be possible under partial load conditions. If the EGR system were completely replaced by emulsion injection (as a method for NOx reduction), the disadvantages of the EGR system would also disappear. Furthermore, the start of injection can be optimized for efficiency.

I would be interested in understanding how the vaporization heat of the injected water and the reduction in expansion work related to the volume increase of the vaporized water, as well as the increase in expansion work, behave.

Is this a case of compensation? Is this a zero-sum game? Or does one effect or another dominate and alter the overall balance?

Thermodynamicists, please respond!

Best regards,

Before I spend too much time worrying about it, I'll wait until those kinds of cars are available for purchase.

The BMW 750 HL is pioneering the use of hydrogen injection.
Having a car like that in my possession, with a gas station right next to it, would be a dream.