Technically you could use any agent, as long as it behaves as an oxidant either before or during combustion. So we could use things such as: nitrogen tetroxide, sulfuric acid, nitric acid, sodium trioxide, hydrogen peroxide, perchloric acid, and so on...
Yet, when we factor in such things as: ease of storage, toxicity, effectiveness, expense, corrosiveness, exhaust byproducts, and all other things associated with the general health and well-being of human life... you end up with good old nitrous oxide.
A *very* small flow of pure oxygen works wonders with some extra fuel ala nitrous. You don't need much. Works even better if you use methanol as the fuel supplement. Just use a small hose discharging into the front of the air pickup for the O, and retard the timing, etc.
Nitrous does work better (charge cooling)and safer, but the installation is a bit more involved.
Water injection can be used it cools the charge and if a small amount is use the water will increase the explosive charge of the fuel being used. There are many systems on the market today.
dilute H2O2 seems likely? Sally supply sells a clear "developer" that called 40 strength. I think its about 15% H2O2. Has anyone tried this????? Seems like it would mix with acetone or alky.
wildbill805
I have read the turboice site and it is the most informative site I have seen on water injection.
I suggest you re read it as it seems to me that it reinforces my view that:-
Water injection suppresses knock.
It does not supercharge.
Under some circumstances it might improve VE by cooling the charge in the manifold a little, but this is not supercharging.
Supercharging is FORCED induction, or the addition of extra oxidising agents.
Water is not an oxidising agent, nor a fuel.
I would check, but alcohol and hydrogen peroxide might be unstable, and therefore dangerous.
Also, care would need to be taken to ensure that there is no attack on fuel system components.
I think from memory, that peroxide is normally sold at a pretty high ph. If so it will rapidly attack aluminium components.
I am reluctant to make suggestions here as it might encourage dangerous experiments, but other strong oxidising agents are Sodium Hypochlorite, Sodium Peroxide, Sodium Chlorite (not Chloride), Peracetic Acid and Sodium Chlorate.
All these chemicals have been known for a long time, as has the fact that fuel and strong oxidising agents makes a lot of power. The fact that they are known, but not used suggests that there is a problem with their use. I suspect that the problems are danger to users, economy, difficulty in controling the reaction in a combustion chamber, by products of the reaction, and corrosion of components.
pat and wildbill thanks for visiting my site and reading over the paper, I am glad it is spreading as it is input from others that really improves it as time goes by.
To clear up what wildbill may have been getting at is I believe in reference first to Sir Ricardo's work showing increased BMEP with water injection (with reduced maximum pressure) and second to Harris' and my reference to the work of Glassman (Combustion, 3rd ed.). These two actually serve to support each other.
Glassman goes through each step of the chemical process behind hydrocarbon combustion. The part I find compelling and actually finely cleared up in my mind exactly why water injection works is based on Glassman's "wet method" for the improved oxidation of CO => CO2 plus his conclusion that the presence of excess hydrocarbons (overly rich settings frequently tuned in turbo applications) inhibits the oxidation of CO2.
This part has not made it to my paper yet and I think Harris in being brief missed to communicate an important item:
"... thus one can conclude - correctly - that hydrocarbons inhibit the oxidation of CO.
It is apparent that in any hydrocarbon oxidation process CO is the primary product and forms in substantial amounts. However, substantial experimental evidence indicates the oxidation of CO to CO2 comes late in the reaction scheme. The conversion to CO2 is retarded until all the original fuel and intermediate hydrocarbon fragments have been consumed."
*Combustion, Third Edition, Glassman, p. 76
While water injection provides additional reactants for Glassman's wet method of CO oxidation. Through the following reaction:
"CO + OH ==> CO2 + H
H + OH ==> H20
H2O + O ==> H2O2
H2O2 ==> OH + OH"
*Harris' EFI note - not exactly in the form that Glassman presents but close and not being an engineer probably equivalent.
According to the chemical properties a majority of the energy released from hydrocarbon combustion is this oxidation of CO, which happens to be a slow and late reaction in the process. The presence of additional water encourages this process and meaning that the reaction occurs more frequently per unit of time. From a layman's point of view and from the view of actually matters in the combustion in a motor - these more frequently occuring reactions result in the inference of increased power. This is because it occurs late (around the time of BMEP) and releases more energy than any other reaction before hand.
When you consider the implications of Glassman's work, then Sir Ricardo's results are more easily understood. WI is causing more reactions to occur right when you need them too late in combustion just ATDC at BMEP.
From a power output view - the result wildbill refers to is observable.
From an equilibrium reaction view - there is no more total energy released as a result of water injection than without. (Though there is more energy released from a 12-13 AFR than there is from say a 10-11 AFR that some turbo tuners using fuel to cool the cylinders end up at. This is because significant amounts of CO do not oxidize to CO2 in the cylinder during combustion.)
In the end I guess I would say that the same energy is released, but the most important energy release becomes more concentrated around BMEP.
This is one of those topics I understand in my head - but I am over my head explaining it. I hope this made sense and that others provide any clarity or corrections.
Of course above I meant that excess hydrocarbons inhibit the oxidation of CO not CO2 when I first mention it.
Also in reference to another earlier question I think weak dilutions of H2O2 have been tried based on what I heard but can't find a study. I also think the conclusion was to the extent it was beneficial it was too difficult to implement generally because of the instability of H2O2 even in "stabilized" solutions. If it could be done Glassman's work on the reactions definitely show that it would be beneficial at a few stages of combustion.
I've assumed the water is an inert carrier (except for latent heat).
The idea is to use a half venturi siphon[in intake plenum]drawing from a seperate ss tank. testing the siphon this weekend. looking for max .75"hg drop on the venturi.
guess at that point i will try sally's h2o2! using a 2.3l ford ranger.
the original question was to gather ideas on other loosely coupled O molecules.
I have a question.
At what temperature does water, break down to its component parts? H2O ----> H2 ----> O
If you spray water on a Magnesium fire it flares up more, why? Because the basic elements are liberated. And you have more O feeding the fire. And I'm sure that H doesn't just sit there watching.
I feel with water injection there are many things going on.
Under normal atmospheric conditions, water will begin to liberate hydrogen and oxygen at approximately 2250 C. Increasing the pressure only results in a rise in the temperature requirement. It is for this reason that hydrogen manufactures rely on chemical reactions or electrolysis to liberate the atoms.
Obviously the temperatures required are well above the temperatures experienced in the combustion chamber. Any liberation that may take place, is most assuredly due to a chemical reaction.
In any event, I would not consider water injection to act as on oxidizer. Power output of a water injected engine is not consistent with a large degree of oxidation occurrence. In my admittedly limited experience with water injection, I did not note any significant benefits when water was injected into an engine that was operating well within the detonation limits of it's fuel.
I was taught that the heat taken in by evaporation of the water caused charge cooling which helps prevent detonation; in a similar way to a modern intercooler on a forced induction engine.
Methanol can be mixed in with the water which helps make up for the power lost by adding just plain water.
