Project: realization of a test bench 2CV pantone engine

[izentrop]

With pantone, consumption may drop, but so does power. Besides, this is what the UTC Compiègne study concluded.
Holds, an old article from 2005 that sums up the situation well http://sourisdudesert.free.fr/index.php ... -paranoia/

[Flytox]

Pantones on 2cv have already been manufactured. You can for example consult the UTC of Compiègne https://www.econologie.com/etude-moteur- ... -3377.html.
Here the plans https://www.econologie.com/plan-du-moteu ... -3384.html.
Now you have everything on a platter;)

The realization of UTC is very nice ..... but did not advance the schimbilick much. They did not measure anything tangible, nor used the engine under load (interest ???????????????) and the exhaust system with all these 90 ° elbows etc ... is a nice nonsense, just capable of suffocating ... an already sluggish engine ... A test bench .... it is not only an engine support outside the car.

I do not yet know how to achieve all the functionality of a test bench despite everything I would like to create the resistant flow with an alternator which would supply batteries. you will understand that this system would be significantly less expensive than a powder brake sized for this application.

Charging batteries seems to me much more complicated to manage and expensive than using simple resistors. There may be even simpler.
Use an output from the gearbox to rotate a shaft and at the end an overhead propeller or in a fleet tank or pump. You can adjust the speed of the propeller with the gearbox. We can find the characteristics of the receiver and calculate precisely the power absorbed just by measuring the speed of the shaft. In addition, the propellers follow a cubic power type law and therefore self-regulate (no overspeed), no control electronics, etc.

[elephant]

Flytox said:

Charging batteries seems much more complicated to manage

Indeed: the charge current of a battery is not constant: it varies according to the state of charge.

On the other hand, pure resistive loads (electric radiators) are much easier to modulate and to objectify (a voltmeter and an ammeter are enough to evaluate the load)

[dede2002]

It should not be forgotten that the efficiency curve of an alternator is also influenced by the load and the speed.
The measurement will not be precise, except for a comparison of consumption at equal power and speed.

For an accurate measurement it is necessary to measure the torque (for example with a capstan and a load cell), the speed with a rev counter, the time with a stopwatch and weigh the fuel with an accurate balance. Torque is the most delicate measure, the others are easy.

[izentrop]

It should not be forgotten that the efficiency curve of an alternator is also influenced by the load and the speed.
The measurement will not be precise, except for a comparison of consumption at equal power and speed.

Precisely, set the engine so that it runs at the same speed with the same load, with or without pantone, for the same duration and measure the difference in consumption.

Of course, in both cases, we first adjust the richness and ignition settings (if any) with the onions.
There can be measurements at different speeds provided that each measurement point is identical in speed and duration and measurement of the corresponding consumption.
http://www.pmga.eu/aimant-permanent/ren ... -compares/

For example 15 min at 1500 rpm, we note the consumption
Then without changing the load, we do the same test with the Pantone device.

I hope I didn't get too annoyed with my rehearsals

[elephant]

We agree: if we do not have too much time, which is often the lot of students, working by comparison on a few points could be effective.

Nothing prevents either, if you have a real electrical charge (and therefore a voltmeter and an ammeter) to make comparisons at equal charge. In this case, it does not matter the efficiency of the alternator: the engine supply is adjusted to obtain the same speed at equal load.

I suppose it is not excluded that the power / speed curve of the engine is modified.

[Flytox]

Whatever system absorbs the power, it must be able to reproduce the same load profile for the version "with" and "without" Pantone.
"Load profile" in the sense that it makes sequences of accelerations stabilization slowing as a "normal" use of a vehicle. If it's just doing a few stabilized points in rpm / load, it's not worth it, the previous testers have not illustrated anything really different.

For a load variation with a ducted aerial propeller, for example, the air inlet can be gated to vary the power absorbed. It should not be too complicated to make a sort of shutter "drawer" whose movement can be perfectly reproducible / programmed to simulate the cycle you need. This system can be mechanically coupled or not to the gas control on the carburetor etc ... It is enough to know precisely the ambient temperature, the atmospheric pressure, the speed of the shaft and the instantaneous fuel flow and you can calculate everything / compare powers, consos etc ...

[camel1]

Hi Guillaume, hi everyone!

Passing on Econology - not often these days, I allow myself to dig up a subject that I had created 6 years ago now ...

Our bench is stored, still operational, even if the study is on standby for an indefinite period ...

My conclusion ? Good luck, but I am afraid that you do not have time to arrive at a convincing result, and that you do not come to conclude that "the Pantone is an urban legend".

The only staggering result we got was on an old 220 D merco, with Didier.
If you want to know more, go here for the bench:
https://www.econologie.com/forums/realisation-du-banc-moteur-de-test-de-reaction-directe-t8466.html
and there:
http://reaction.directe1.free.fr/banc.htm

And here for the merco:
http://reaction.directe1.free.fr/Merco220D/merco.htm

These different achievements took me thousands of hours, between hard and soft, not counting the tests themselves ....

Good reads, and good thinking!

Regards

Michel

[Christophe]

Hi Michel, glad to see you back here!

BMW engineers have also worked well on the issue (with the means they have ...) and we released a car with water injection: https://www.econologie.com/forums/injection- ... 13753.html

A series assembly is mentioned!

Here are 2 of their patents, 1 of which contains a very interesting diagram on the management of water injection: https://www.econologie.com/forums/brevets-bm ... 13760.html

All the other manufacturers have certainly also worked on the question ...