On the Explosion Hazard and LAS. If the Ares I LAS can pull a crew away from an exploding SRM then I wouldn't be so sure that one couldn't be devised to protect a crew from a HTP stage.
Unlike LOX one, which can only burn ...
Can we use the correct terminology please?
Quote from: clongton on 03/23/2009 10:56 amCan we use the correct terminology please?From where I stand, gospacex did use the correct term - a "LOX one" as in engine means it has a fuel in addition to LOX. If the two are not well mixed, no detonation is possible. Any by definition, keeping both fuel and oxidizer (in this case LOX) in separate tanks prevents them from mixing. I don't see that statement as implying it's LOX itself that burns.
What did I just say above? He did NOT say "Unlike LOX, which can only burn" he said "Unlike LOX one [i.e. fuel/LOX combo], which can only burn". I'd think the vast majority of people here know oxygen doesn't actually burn, but maybe it's just my impression.
I have seen professors ask students to leave the class when they did that, and my request was for folks to take pains to use the proper terminology and use it correctly. This isn't a rap around a campfire. Perhaps I'm old school, but I like to know that the terms I see used in a technical discussion are actually there in the dictionary and continue to mean what they have always meant.
Quote from: gospacex on 03/23/2009 04:33 amUnlike LOX one, which can only burn ...gospacex, this is a general comment and not aimed specifically at you.I keep seeing this statement ("Unlike LOX one, which can only burn") and others like it all over the place, and while I know it's a fine distinction, it is *not* true that LOX (oxygen) burns.
Quote from: clongton on 03/23/2009 10:56 amQuote from: gospacex on 03/23/2009 04:33 amUnlike LOX one, which can only burn ...gospacex, this is a general comment and not aimed specifically at you.I keep seeing this statement ("Unlike LOX one, which can only burn") and others like it all over the place, and while I know it's a fine distinction, it is *not* true that LOX (oxygen) burns.You are right. My phrase was "Imagine a manned rocket at the pad fueled by HTP. Unlike LOX one..."Correct phrase should be "Imagine a manned rocket at the pad fueled by HTP. Unlike LOX fueled one..."(I'm not sure whether it's 100% correct to say "fueled by [some oxidizer]", but nothing better comes to mind)
Quote from: sbt on 03/23/2009 07:07 amOn the Explosion Hazard and LAS. If the Ares I LAS can pull a crew away from an exploding SRM then I wouldn't be so sure that one couldn't be devised to protect a crew from a HTP stage.SRM's don't detonate
a) Whether HTP actually Detonates in the true sense (i.e. reacts along a shock front) or if it deflagrates (or something else)?b) If the behaviour of bulk HTP in a stage is understood – does the 'whole lot go up' in one instantaneous bang or does the oxidiser disperse so that only part goes up?
Mind you, this is for info only, not because I actually believe that anybody is going to build a large HTP stage nor am I particularly advocating one – just doing thought experiments.
BTW, do you have data on HTP/C3H8 pair?
Propellants MR dp (kg/L) ve (m/s) Id (Ns/L)O2/H2 5.0 0.3251 4455 1448O2/H2 6.0 0.3622 4444 1610O2/H2 7.5 0.4120 4365 1798O2/CH4 3.6 0.8376 3656 3062F2/H2 14.6 0.6553 4704 3083O2/C2H6 3.2 0.9252 3634 3362O2/C3H8 3.1 0.9304 3613 3362O2/C3H4 2.4 0.9666 3696 3573O2/RP–1 2.8 1.0307 3554 3663O2/C7H8 2.4 1.0954 3628 3974HTP/C3H8 7.8 1.2284 3242 3982HTP/C3H4 6.5 1.2553 3319 4166HTP/RP–1 7.3 1.3059 3223 4209HTP/C7H8 6.6 1.3496 3288 4437F2/NH3 3.4 1.1770 4115 4843
Along the side of the case. It's a zipper.There's occasionally talk of being able to shut down a solid without destroying it by jettisoning the nozzle with ordnance, but that joint itself would be unsafe.