Burning Model Rocket Engine In Liquid Nitrogen - 4K Slow Motion

[Winston]

Why? Because it draws YouTube viewer hits...

[video=youtube;E5r2N9yQi5A]https://www.youtube.com/watch?v=E5r2N9yQi5A[/video]

 

[fyrwrxz]

I'll admit-I HAD to watch! I'll also admit working with it and doing stupid stuff, which is as far as I'll admit....LOL!

 

[Nytrunner]

Has he already done it underwater? It'd give much better video representation.

So what are the thoughts on the casing failure? Extreme cold? slightly thin casing? It would have CATO'd anyway?

 

[K'Tesh]

Has he already done it underwater? It'd give much better video representation.

So what are the thoughts on the casing failure? Extreme cold? slightly thin casing? It would have CATO'd anyway?

The cold affects the propellant in a different way than the casing material. The propellant shrinks more than the paper, and thus the reaction can propagate faster than it is intended to... This causes an overpressure and... BOOM!!!

 

[cobra1336]

He has gloves on and a face shield....and shorts??

 

[Peartree]

But to answer your question, yes this has been done underwater. Not sure if it was this guy or someone else but I remember seeing it posted here somewhere.


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[K'Tesh]

But to answer your question, yes this has been done underwater. Not sure if it was this guy or someone else but I remember seeing it posted here somewhere.

It was done by the same guy...

 

[Winston]

The cold affects the propellant in a different way than the casing material. The propellant shrinks more than the paper, and thus the reaction can propagate faster than it is intended to... This causes an overpressure and... BOOM!!!

That's exactly what I was thinking - grain separation from the casing perhaps with the added "bonus" of cracks in the grain due to thermal shock and shrinking. I'm impressed that the ignition went so well, perhaps not so surprising for BP. Try that with composite motors which too often have ignition issues even at 74F ambient.

 

[tightwad]

This guy must have money too burn! :wink: Too bad he isn't flying rockets.

 

[KarlS]

He also did one in a vacuum. All are on YouTube, I think.