This is where I started;
DixieProMod wrote:
I do NOW appreciate that keeping nitrous liquid, must be darn important. I thought I "understood" the principle of that, but didn't "appreciate" what it REALLY meant. I kinda' thought Trev might be a little crazy, when he initially told me to start running with 3 additonal lbs of fuel pressure, above what I normally ran (I ended up running 2+lbs more.) Even though the system made more power than the one it replaced, nitrous consumption actually went Down 25+%. To someone who has tuned 2 & 3 nitrous systems for years, this indicated a BIG change/difference. In otherwords, less nitrous ended up being more. I'm still kinda' thinking about that one.
It's only SINCE that i've tried to understand WHY..........
And it hasn't been, isn't and more than likely won't be easy !
Brett > Dead right, we've got so many "laws" colliding working out what's really going on 'aint easy, but like Denny says
Racetested wrote:
We are good at applying logic and common sense but I feel there is that void of physics not being fully undertsood. If we can learn more about physics that can be applied then look out as nitrous can take one major leap.
And he's right.
Trev, through whatever mystical means keeps on making nitrous faster (by using less) and as much respect as i have for his "UNcommon" sense it would be nice to have the theory behind it in black and white so to speak.....
I see you're not feeling yourself again just yet Trev, or i wouldn't be posting stuff you already know.......
Or are you making me do this for effect again ? I'm ill you know !
The circumstances surounding your sample matter a lot, being such a bad conductor it carries it's history with it for a good long while.
If the bottle you drew the sample from had recently been filled, it's entirely possible the contents had a physical temperature of maybe -20c but as the liquid contacted the bottle surfaces, that "boundary layer" was heated to "ambient" and that small total amount of liquid "boiled off" and created a bottle pressure equivilent to the ambient temperature.
OR simply the pressure differential of filling and the disturbance to the liquid created enough gas by reducing it's boiling point enough.
ERGO; The classic "fresh fill bottle, high pressure that drops like a stone during a run"
Liquid nitrous can be stored at ambient temperatures as long as the pressure is high enough, how much pressure would you need if it's temperature was low enough ?
Atmospheric maybe ?..................
Now prevent it transfering heat by putting it in a plastic cup, a liquid thats terrible at transfering heat let alone transfering heat from a layer of boiling off gas and I don't see 30 minutes as unreasonable.
Now did you think of dropping a temp probe in there while you stared at it ?
As far as temperature / bottle pressure goes we only need to apply enough heat to cause enough liquid to boil off and we have our pressure.
If the bottle was kept still and we drew from the bottom then 90% of the contents could be at critical temp, the bottle showing critical pressure yet we'd still have liquid at the outlet.
It's weird old stuff but at this point it's still behaving as any hot / cold, dense / less dense, gas / liquid would, cold and dense stuff at the bottom.
Once the entire contents were at critical temp we would start dispensing actual supercritical nitrous.
They were having this problem at one of the hybrid rocket competitions last year, they fill very slowly to get a maximum fill but without insulation and with high ambient temperature donor bottles they were going supercritical while on the launch pad.
Que lots of fizz with no pop !
Bear in mind these aren't sealed bottles as such and are very thin walled.
After quickly reading this through i've realise two things;
I still don't feel very well and don't make much sense.
None of this makes us go faster
And quit calling me educated ! I'm just a dumb grease monkey who's never done and isn't likely to do 8 seconds, but at least it's not a load of endless technobable that goes around and around without actually saying anything..............