Operating principle of the GP Plus system: an instant steam generator to power a GP system (Gillier Pantone)
The “GP +” system is an evolution of water doping with bubbler, called the GP system (in honor of its first experimenter, the farmer Antoine Gillet) by replacing the bulky bubbler by a steam generator.
It is this assembly which was carried out at the Mayor of Vitry sur Orne.
This involves replacing the bubbler (see construction plan for a water-doped engine on this page) by an instantaneous steam generator (GVI) to compensate for the disadvantages of the principle of the bubbler (inertia and space in particular).
Principle of operation
It is an annular exchanger, positioned in the axis of flow of the exhaust gases, which come into contact with the inner and outer walls. Its dimensions (therefore its exchange surface) condition its ability to rise in temperature and its capacity to produce steam, knowing that we are looking to make, not dry and superheated steam but wet steam or rather a mist of heated water since the temperature remains below 100 ° C. This is explained by ionization theory.
In fact, it will be sized according to the engine capacity and its gasoline or diesel type (for the moment, it has only been tested on diesel, some experimenters are currently trying on gasoline, their experience feedback will come a bit later…)
Problems related to the use of a bubbler or evaporator
The idea which governed the design of the GVI, comes from the enumeration of the defects inherent in the principle of the bubbler:
- high thermal inertia (it is necessary to heat a large quantity of water, which introduces a significant phase shift between the production of steam and the "needs" of the engine, etc.)
- the fact that, precisely, the engine of a vehicle, unlike a tractor or a generator, works in variable load regime, and that consequently, the reactor must be able to react quickly to these variations, which the bubbler is unable to do ...
A little anecdote: some experimenters have noticed a loss of engine braking on descents. The explanation for this problem comes from the fact that the engine has produced significant work in the climb phase, gradually heating up the bubbler, which will start to produce full steam ... at the top of the hill, and which will continue to heat up. do it in the descent phase, where the engine should only produce braking ... this one receiving steam which will provide some work partially canceling the engine braking effect !!
- the very real problem of space in an engine compartment, which arises almost systematically for the director, with sometimes unfavorable distances forcing him to use long hoses ...
- implementation also complicated by the water heating system (by exhaust gas or connection to the cooling circuit, etc.)
- the actual manufacturing, which always remains a big chunk, in terms of raw material, manufacturing time, embodied energy, and development
The answer to these problems by Instant Steam Generator
The GVI seeks to respond to all of these problems:
- its small dimensions give it a very low thermal inertia
- its heating by the exhaust gases allows it to closely follow the engine load variations
- its integration into the exhaust line, as close as possible to the reactor inlet, elegantly circumvents the problem of space, as well as the possible recondensation of the steam in its path to the reactor ...
With the concept of GVI, we end up with a simplified "in line" design, which requires only a simple modification of the exhaust line, with an integrated reactor as close as possible to the outlet of the exhaust manifold, followed by the GVI. In terms of connection, the assembly receives a water inlet for the GVI, a tapping hose on the intake manifold, and an air inlet hose connected to the air filter. It's hard to make it simpler…
This type of construction therefore becomes accessible to many DIY enthusiasts, being very economical and very quick to manufacture ...