A pulsejet engine is a type of jet engine in which combustion occurs in pulses. A pulsejet engine can be made with few or no moving parts,and is capable of running statically,it does not need to have air forced into its inlet typically by forward motion.
source/image(PrtSc): Robert Maddox
Pulsejet engines are a lightweight form of jet propulsion, but usually have a poor compression ratio, and hence give a low specific impulse./Robert Maddox
In this build video I am building my Maddoxjets 100 pound thrust pulsejet engine running on gasoline.This engine runs on gasoline and uses two high pressure automotive fuel pumps.This is a great engine to run just for fun on a stand or for mounting up on a go kart or motorcycle and I have used.
One notable line of research of pulsejet engines includes the pulse detonation engine, which involves repeated detonations in the engine, and which can potentially give high compression and reasonably good efficiency.