Wiki entries? Really? Diesel engines are compression ignition, glow engines function from a chemical reaction with the fuel.
Actually, no. It's a mechanical catalytic reaction, not chemical. Heat from the compression stroke is still required for ignition. It's a diesel engine, albeit a different one.
There are distinct differences between a "diesel" and a "glow" engine, but the topic is RC diesel engines. As has been said, typical model diesel fuel is kerosene, castor oil, and ether. Some add ignition improvers as some engines are harder to get started and idle without it.
Model diesels have an advantage over glow engines in that the fuel is more completely combusted so there is less waste, diesels require less fuel to do the same amount of work as a glow, and the engine produces a substantial amount of torque compared to glow. The downsides are the smell - it really hangs on you, and you have to adjust not only the carburetor, but the compression screw as well. In an airplane scenario, thats easier to do than a car being that the loads imposed on the engine are so vastly different. IMO, a diesel would be much better suited for a rock crawler or non-racing MT, 1/8th scale or larger. However thats only if one really wanted to experiment badly..
In the airplane world, its not unheard of running 12x6 and 13x6 props on a .25/.30 diesel. My buddy's PAW .15 turns a 9x6 at 10,000-11,000rpm. My .29 glow, twice the size of the .15 turns a 9x6 at just shy of 13,900 on an untuned full-wave pipe. I find the PAW .15 numbers impressive. A sport glow .15 would be turning an 8x3 or 8x4 or even 7x4's if you want some real rpm from it.
I dont think Diesels should be put in cars. Converting a car glow engine over to diesel would likely require plugging of the boost port in the case, and using a much smaller carb. The timing on car engines is pretty gnarly compared to model diesels. many diesels dont have a boost port to start with.
Just my take on it..