Saturday 6 December 2014

FUEL, FUEL DELIVERY SYSTEM, IGNITION

As part of the Lockwood-Hiller I will need to choose a fuel for it to run on and how I will provide this to the pulsejet.

Pulsejets seem to run on virtually any fuel, 'if it burns, you can probably run a pulse jet on it' (8.1).

Although they can run on virtually anything, propane seems to be the best option for me; with it's boiling point being so low, it can be supplied straight as a gas-propane pulsejets are 'one of the easiest to start' (1.2). It is also easy for me to source in compressed cylinders and doesn't require any sort of vaporizer or pump. 

To supply the fuel most people seem to use what is called a fuel rod to do this but an alternative is injecting the fuel down the intake through to the combustion camber. I'm going to opt for the fuel rod method as it's the one that's most documented and therefore familiar; however it will require more work.  This shouldn't effect the rest of the design so won't restrict any progress.

I also need to decide how to ignite the fuel-Bruce Simpson outlines how to use a spark plug (1.1), however, Colin Furze just ignites the gas using a blowtorch at the intake. I think I'm just going to use this method to keep construction simple for the time being.
The fuel delivery system will also need designing; although Bruce Simpson recommends 2 valves: one for idle and one for full throttle/finer adjustments (1.11), I just want my pulsejet to run so am just going to use a single one. If it runs I can always alter the delivery system in retrospect to improve performance.

No comments:

Post a Comment