Cars use gasoline but jets use something closer to diesel, maybe kerosene, that’s less combustible. Wouldn’t they need a _more_ volatile or explosive fuel to get the most thrust for performance?
In: Engineering
You wouldn’t want your fuel to actually blow up, then the pods on those engines would explode every time you introduced fuel! You want a controlled burn to accelerate the gases and turn the turbine which turns a shaft that turns a huge fan in the front which puts basically *just enough* air through the low and high pressure compressors while the vast majority of the air moves around ducts and is never combusted. That is the principle operation of a turbofan engine.
That is the difference between a turbine reaction and a typical piston combustion engine. In a piston engine the ‘power’ phase needs to combust the fuel and air mixture with enough force to blow the piston down and the other ‘side’ of the crank up (thus causing another piston to go into compression or exhaust) and have enough twisting power so that if you connect something to the crankshaft you can impel motion. To do that you do need considerable explosive force. A turbine engine produces forward motion by moving air molecules that were in front of the engine to the back of the engine. The fan in front of the engine gobbles up a bunch of air and farts them out the back. It is why we sometimes call them ‘air eaters’. In order to do this we need to figure a way to turn the turbine blades which power the big fan in the front and the compression stages. A wind or water turbine can do this just by the pressure of the wind or the water, the mechanical force comes from gravity or the uneven heating of the earth, but a gas turbine slung to an airplane wing has to create its own. So, if you light up some pressurized air and fuel, you can blast the turbine with hot gases with enough energy to turn the whole shaft. It is more desirable to have a slower and more predictable burn than a fuel that will easily explode.
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