03-03-2011, 11:06 AM
PRESENTED BY:
SACHIN BHAT
SHARATH KAMATH
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PULSE JET ENGINE
What is Pulse Jet ?
• Simple form of internal combustion engine
– Combustion occurs in pulses
» Termed deflagrations
» Characterized by sudden rise in temperature and pressure followed by a rapid subsonic expansion
– Propulsive effort is a rearward reaction to hot gases
HISTORY
• Patented in 1906 by Russian engineer V.V Karavodin
• In the 1933 German engineer Paul Schmidt re-discovered the principle.
• First jet-powered fighter aircraft was developed in 1944. It was the V-1.
• The V-1 was powered by the Argus As 109-014 pulsejet engine.
TYPES OF PULSE JET ENGINES
• Valved Pulse Jet Engine
• Valveless Pulse Jet Engines
PULSE JET ENGINES
• Comprises:
– Intake fitted with an one-way-valve
» Reed valves (valved)
» Aerodynamics (valveless)
– Combustion chamber
– Acoustically resonant exhaust pipe
VALVED PULSE JET ENGINE
• Air flows through the intake .
• Mixes with fuel.
• The valve is closed.
• The ignited fuel-air mix propels the craft
VALVELESS PULSE JET ENGINE
– No mechanically moving parts (valves)
– Aero dynamic valves
» Mass of intake air used as valve
– Thrust forces produced in two distinct but synchronized mass acceleration events per cycle
WORKING CYCLE
• Induction/Ignition
– Air forced through the front
– In most engines fuel is added through venturi
– Ignition within the combustion chamber occurs
• Combustion
– High pressure is raised by combustion of air/fuel mixture
• Exhaust
– The valve is shut sealing the intake holes
• Cannot exit forward through the one-way intake valve
– Exits through the exhaust tube, which provides the thrust
• Compression
– Low pressure is created within the chamber and fresh air is sucked in
– Some of the hot exhaust gases are sucked back into the engine
– Reflected high pressure wave from the tail pipe compresses the charge, which is ignited by heat from previous cycle
ENGINE DESIGNS
Argus As 104
Escopette
The Logan
Chinese CS
ADVANTAGES
Extreme simplicity
Low cost of construction
Extremely efficient combustion while producing almost no hazardous pollutants
Medium to largest engines can burn almost any flammable material
DISADVANTAGE
Poor fuel economy
High noise levels
High radiated heat levels
Smallest engines only successful with extremely fast-burning fuels
APPLICATION OF PULSE JET ENGINES
FUTURE OF PULSEJETS
