10C10.35 - Pulse Jet Engine

Code Number:
Demo Title:
Pulse Jet Engine
Action Reaction, Jet Engines
Area of Study:
Pulse Jet Engine (Dyna-Jet), Lighter Fluid (Fuel), Induction Coil, Propane Torches, Eye and Hearing protection, and Air Compressor (If Needed).

See also 1N10.75 in Mechanics.

Place the engine cart behind the bench so that it is well away from the students (it gets very hot when running).  Hook the air line for the engine to the compressed air in the lecture room.  Fill the fuel tank with lighter fluid (this gives about 25 seconds of run time).  Pre-heat the combustion chamber with the propane torches so that portions of it glow red hot.  Continue to heat the chamber until the engine starts.  Turn on the induction coil and then carefully turn on the compressed air so that the air/fuel mixture is forced into the engine by way of the engines "venturi".  When the correct flow rate is reached the engine will pop and then run continuously.  At this time the pre-heating with the torches can be discontinued, the spark coil turned off, and the compressed air flow can be turned off.

This engine is very loud so be sure to tell everyone in the audience to cover their ears.  It is very impressive to turn out the lights when the engine is running as the combustion and exhaust chambers glow red hot, and you can also see the shock wave striations in the exhaust gasses exiting the engine.

  • Doug Stith, "The Resonating Raft", TPT, Vol. 54, #9, Dec. 2016, p. 570.
  • Brandan-Gillogly, "Hot Rod Anything! Behold, Thrust!", Hotrod Magazine, May 2013, p. 16.
  • "Build a Pulse Jet", Popular Mechanics, Apr. 2011, p. 76.
  • Seth Porges, "Welcome to the Brooklyn Academy of Mechanical Arts and Ballistic Sciences", Popular Mechanics, May 2010, p. 75.
  • J.H. Lemelson and R.F. Probstein, "Model Jet Planes Top 140 m.p.h.", Popular Science, Aug. 1948, p. 164.
  • "First Jet Engined Flight", Guinness World Records, 2003, p. 154.

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