Interesting study Moose.
I'm not sure the hydrogen would have enough residence time with the fuel to impact the cetane number of the fuel.
The hydrogen would likely combust before the main fuel. I'd be willing to bet that you'd get knocking and a bunch of unburned fuel if you actually ran your tests and watched the outputs.
I was sort of under the impression that higher hydrogen content improves the octane number, not the cetane number... and that the cetane number is what one has to key on when predicting autocombustion.
Any clarification would be excellent!
As for hydrogen, it will have its utility.
You could create and move fresh water to a water short area via electrolysis and pipeline transportation of the produced hydorgen. On the other end, you'd combust the hydrogen to create fresh water and re-capture some of the electricity that was input into the process. I've got a project that I am working on in the back of my mind to this end...
I don't see a hell of a lot of utility for hydrogen when it comes to transportation. Its energy denisty is too low and the investment in infrastructure to make this happen is a significant barrier.
ESPECIALLY when you consider how close we seem to be on manufactured oil (i.e. biomass fuels). What's the economic incentive for hydrogen when you have a renewing supply of oil? None. (not saying that renewing supplies of light oil are right around the corner, either...)