Thx Steve
Perhaps the geet has to be good and hot before switching over to diesel or oil.
Perhaps build a second bubbler so you can switch between fuels, with engine running, using taps/vaulves.
So as the rod length decreased the outer tube temp went up.
I think this is because less heat is being abzorbed by the inner tube.
Because the rod causes the gas molicules to speed up and collide with the tube surface more; absorbing more heat.
(Water absorbs heat better than almost anything else)
This restricion also means that the engine has to do more work sucking in the gas and may seem to run out of breath.
Work that gould be set to a usefull task.
When the rod was removed; the restriction was removed, which is why your genset was happiest.
I fear that your geet may just be pyrolysing/vapourising the fuel with very little Autothermal reformation going on.
The french are also using waste exhaust heat to pre boil the water before feeding it to a geet.
I think this increases the amount of Steam Reformation that happens in the geet.
Another way of getting more heat into the intake gas, without the restriction is increasing surface area.
Finned, spiral, heat exchanger tube is available.
However; I would try a 'propeller' in stead of a rod to get the gass to spiral and thus to come into contact with the tube surface more.
You should see a small drop in outer tube temp if you try this.
Its possible that the geet was simply changing your diatomic H2 to monatomic H+H which is why it ran on less H/2.
This in itself would be a valuble lesson:
You can use waste exhaust heat to get more out of your Hydrogen.
Whats the metal catalyst for this again?
Hope that helps with your think Steve.
