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Rotary Pulse Jet Engine


Rotary Pulse Jet Engine
The Concept IC Engine
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The Pulse Jet Engine
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click on image to start animation:-


The image shows an alternative method for raising and lowering of the pistons in order to compress fuel and facilitate fuel/air intake. This design uses only 12 moving parts in the whole engine. The central stationary cam maybe modified in shape to include a cooling cycle for the combustion chamber The central stationary cam is fixed onto the two halves of the outer housing allowinbg free rotation of the inner rotor.Click on image to see animation.

Outlined at this site are two brilliantly innovative engine designs , the first is the "Rotary Pulse Jet Engine " an animation of which is given at the top of this page . This engine uses The Pulse Jet Technology (Click on link to see how the pulse jet works.) , developed by the Germans for their V2 bombers or "buzz" bombs , to power the engine.

As is illustrated in the animation , the combustion cycle of the Rotary Pulse Jet Engine works as follows:-

(1) A fuel- air mixture is forced into the combustion chambers by the vacuum effect created bv the piston moving down the cylinder , entry of fuel may also be aided by a turbo-charger.

(2) The fuel- air mixture is then compressed in a sealed environment by closing of the intake valve and the upward movement of the piston.

(3) The compressed fuel-air mixture is ignited resulting in rapid expansion of the fuel.

(4) The heated fuel-air mixture is explosively ejected through a nozzle resulting in the
rotation of the rotor in the direction of rotation.

The advantages of such an engine are that :-

(a) It eliminates the need for linear to rotary conversion.

(b) It has the power of a jet engine but uses an intermittent instead of constant system of combustion, resulting in lower fuel consumption.

( c ) A pulse - jet engine has a much lower rpm 50 - 60 cycles per second , than a turbine
25,000 - 40000 rpm, which means that the transmission is easier to link and design

(d) The greatest advantage of the Rotary Pulse jet engine is that every phase of its power output can be controlled and therefore makes it ideal for linking to a computer to get maximum performance.

The basic design of the Rotary Pulse jet engine is extremely simple and would require only 40% of the parts needed in a conventional IC engine. The rotor and shaft inclusive of the pistons could be made far lighter than the weight needed to be moved in a conventional engine such as the crankshaft , fly-wheel , cam-shaft , connecting rods and so on , thereby giving the engine a much greater size to power ratio.
Exploded view of the Rotary Pulse jet engine:-


As can be seen in Figure 1. The Rotary Pulse Jet Engine is very simple in design , it consists of a rotor , enabled for movement in one direction only , fixed to an axle of which it is an integral part , revolving inside an outer housing. The edge of the inner rotor contains variable volume combustion chambers which contain spark plugs and pistons , the spark plugs are provided high voltage through the outer housing in much the same way that the rotor in the dulco system in conventional engines supplies high voltage to each cylinder in turn , the pistons are used to facilitate intake of fuel and air by creating a vacuum and to compress the fuel -air mixture , they are not used to transmit power as in conventional engines. Each combustion chamber is equipped with an intake valve and an exhaust nozzle. The valves are opened and closed through interaction of the rotor with the inner surfaces of the outer housing, similarly the pistons also are moved up and down the cylinders by the interaction of the piston shafts with the stationary central cam , this means that there are only 12 moving parts in the whole engine , compare this with the more than 400 plus moving parts in an IC engine. The pistons are held in place by their position on the cam there is no need for ratchets,to hold them in place during ignition and to release them during intake of fuel. Fuel is supplied to the inner rotor through the outer housing and used fuel products are similarly routed through the outer housing.Lastly , there have been a lot of questions on the size of the engine. Using 5.5" dia cylinders with a dispacement of 2" and a compression ratio of 9.5 : 1 the size of the engine will be 18" in diameter , this can be reduced to 14 " if the combustion chamber is displaced relative to the cylinder. It must be noted that the cylinders and pistons are completely isolated from the combustion chamber through the use of a one way valve and the pistons do not therefore come under any mechanical or heat pressure.

Click here to see details of home experiment:-