roughly how a jet engine works

  • left fan pulls in atmospheric air to feed into the combustion engine. extra air goes around the engine and also produces thrust
  • air gets compressed, then fed into the combustion engine. since combustion needs oxygen, compressed air is better since there is more oxygen per unit volume and therefore you can burn more fuel with the same volume of air. another reason is that compressed air is also higher pressure than the atmospheric air that came in. buring fuel at high pressure produces more work than burning fuel at lower pressure, and that net difference produces more work than work than the work needed to compress the air.
  • hot combustion gas gets expelled rapidly, producing thrust and spinning the right fan, which powers the generator.
  • thrust comes from two places. (1) is from the air pushed backward by the bigger left fan and (2) is from the host exhaust gas leaving the combustion engine on the right
  • the left and right fan are connected electrically. this means that we use some of the combustion air to spin the right fun which captures energy to power the left fan, which spins and keeps air coming in.