Converting a Small Engine to Run on Hydrogen: Challenges & Questions

[mattpbarry]

For a Science Expo project I will be converting a small engine to run off hydrogen. I have in mind a cheap four stroke water pump. My father said he is willing to let us use http://unitedpower.en.alibaba.com/p...linder_engine.html?tracelog=cgsotherproduct1" but we may just buy a new, smaller engine (about ZAR 350). I have done some research and have come across a number of concerns I would need help with.

Firstly there is the issue of fuel delivery. I assume the carburetor in the motor uses a float valve and will therefore not work with a gaseous fuel. Is this a major concern? What do LPG engines use? I have heard about spark plug fuel injectors but I don't know if anybody makes the commercially. I want to do minimal damage to the engine so drilling new holes for direct fuel injectors is out of the question. What should I use? Also is pressure a major concern as well? Would a regulator have to be fitted? Obviously things such as non-return valves and flame retardants would have to be used.

Secondly is the fuel tank. My school is willing to supply us with some hydrogen but obviously we cannot take their entire tank (which is quiet large) to the expo venue or home. So would it be possible on a small engine to use a balloon or a soda bottle as a fuel tank. We could do it in a network (i.e. multiple bottles) to increase storage if necessary but obviously pressure would become a problem. The fuel consumption on our engine is given as 417.1g/kWh for petrol. I don't know what the fuel consumption would be with hydrogen.

Finally engine timing. What would the ideal engine timing for hydrogen?

Any help/references would be most appreciated. Please feel free to raise any concerns you may have.

 

[Achy47]

First of all, congratulations on your project idea! Converting a small engine to run off hydrogen is definitely a challenging and innovative project.

In terms of fuel delivery, you are correct in assuming that the carburetor in the motor will not work with gaseous fuel. LPG engines typically use a different type of carburetor or a fuel injection system specifically designed for gaseous fuels. Spark plug fuel injectors are available commercially, but they may not be suitable for your project as you mentioned not wanting to drill new holes in the engine. One option could be to use a conversion kit specifically designed for small engines, which would include all the necessary components for converting the fuel system to run on hydrogen. This would minimize any potential damage to the engine.

Pressure is definitely a concern when using gaseous fuels, so a regulator would need to be fitted to ensure the correct pressure is maintained. Non-return valves and flame retardants are also important safety measures to consider when working with hydrogen.

As for the fuel tank, using a balloon or soda bottle as a fuel tank for a small engine is not recommended. These containers are not designed to handle the pressure of gaseous fuels and could pose a safety hazard. It would be best to find a suitable and safe fuel tank specifically designed for gaseous fuels. The fuel consumption for hydrogen will vary depending on the efficiency of the conversion and the specific engine, so it would be best to do some testing to determine the fuel consumption for your particular setup.

In terms of engine timing, the ideal timing for hydrogen will depend on the specific engine and its design. It is important to consult the manufacturer's specifications and possibly consult with experts in the field for guidance on this matter.

I hope this information helps and I wish you all the best with your project. If you need any further assistance, please do not hesitate to reach out to me or other experts in the field. Good luck!