heat resistant mortar

[Dang911]

Has anyone seriously considered building a pulse jet out of clay. You could even build one out of cement if you made a nice mold. They might be a little heavy, but they would have very high efficiency. If vibrations are a concern, I'm sure a thick enough wall could withstand all the shock of a normal pulse jet.

[tufty]

Has anyone seriously considered building a pulse jet out of clay.

That's what we're talking about, kinda. Ceramics that are designed for high-temperature applications.

You could even build one out of cement if you made a nice mold.

Cement (At least of the non-refractory type) has a distinct tendency to explode when treated to high temperatures. At best you'd have massive spalling, at worst you'd get bits of cement flying everywhere. A pulsejet made from a block of refractory cement would likely work, but would be rather expensive to construct, and you'd have to be very sure that any moisture was driven out before firing it up - the thicker the refractory the more moisture you have and it takes ages to fire it.

Similarly ceramics, the thicker something is, the harder it is to fire without cracking. I'd personally think that thinner rather than thicker is the way to go.

Simon

[metiz]

its "openhaarden kit" translated thats something like "fireplace kit" its heat resistant to 1250 degrees c bonds to metal and stone (amongst others) and is (usually) used to fill up cracks in a fireplace. it costs about €8.50 per 200ml thats about 5 pounds.

[kid jansen]

I doubt that kit used for fireplaces is temperatureresistant till 1250°C.
I know that stuff, I used it for "glueing" together my uncle's barbeque.
It should be pretty temperature resistant, since charcoal in a stone barbeque can reach high temperature, but 1250°C is really high.

[metiz]

I can't help it, thats what it says

*edit* kid jansen check www.bison.nl then go to "producten" type in "kit" choose "openhaardenkit" there you can see the specs and even a picture of one of those bottles saying "1250 c"

[kid jansen]

I see, but still I doubt it, perhaps I should test it once. If got a digital thermometer and a soldering torch, and I must have some pieces of sheet metal as well.