difference between valved and valveless

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waynefitz89
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difference between valved and valveless

Post by waynefitz89 » Thu Oct 29, 2009 2:38 pm

as a student in c.i.t. (ireland) i've been given a project which involves building a pulse jet engine and coming up with a new application for the engine, but i'm having difficulty understanding the design factors ( power output etc, etc) of pulse jets mainly the difference between valved and valveless engines ( besides the obvious one has valves and the other doesn't) . i'm also having difficulty in understanding how the different dimensions effect the engine ( combustion chamber diameter, ete ,etc). any help with design information or applications would be greatly appreciated.

metiz
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Re: difference between valved and valveless

Post by metiz » Thu Oct 29, 2009 3:05 pm

If you just need to build a pulse-jet and figure out something different to do with it, I'd advice to just stick with that. The questions you ask can not realy be answered with x=1 and y=2; there's a lot that changes behavior in any given engine causing it to deviate from a given model.

Look in the free plans section on top of the valveless forum for some good plans. Look through the valveless forum itself for some more good plans. A real kicker is Beck Technologies 3lbs Thermojet. It's powerfull for its size and easy to build and start.
Last edited by metiz on Thu Oct 29, 2009 4:45 pm, edited 1 time in total.
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ace_fedde
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Re: difference between valved and valveless

Post by ace_fedde » Thu Oct 29, 2009 4:16 pm

And keep us posted about your project!! :D

Fedde
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waynefitz89
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Re: difference between valved and valveless

Post by waynefitz89 » Wed Apr 28, 2010 7:28 pm

well we've made the thunderchine lovly design what more could we want.
but with that comes the major problem cant get the thing to sustain on its own and it due tomorrow for an exhibition

Bruce Simpson
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Re: difference between valved and valveless

Post by Bruce Simpson » Wed Apr 28, 2010 11:23 pm

waynefitz89 wrote:well we've made the thunderchine lovly design what more could we want.
but with that comes the major problem cant get the thing to sustain on its own and it due tomorrow for an exhibition
There are some significant issues with the Tunderchine. I had the same problems with the one I built -- wouldn't start very easily at all and would not sustain reliably.

On investigation, it's a very "borderline" design so even when built with great precision it'll never be a reliable engine. Too much emphasis on getting maximum power output and not enough consideration for the small factors that can really play havoc with one's theoretical model.

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