Thanks chaps.
Thanks to all for contributions. The application I am looking at is very small gas turbines for model aeroplanes and UAVs. In models they are very heavy on fuel consumption and I suspect that there are considerable amounts of unburnt hydrocarbons being cast to the wind. The scale issue arises big time with residence time in the combustors being very short indeed. I was wondering whether spraying water and methanol (commonly used for model IC engines) laced with nitromethane would allow the spray to atomise in the compressor and make the whole thing more efficient. I guess the only way to find out is to buy one and try it out. Be ready for loud noises in North Wiltshire!!