Go Down

Topic: For Sounding Balloons or Red Bull Stratos: Why not use hydrogen over helium (Read 7276 times) previous topic - next topic

Coding Badly

And there was oxygen and a spark, even if the hydrogen made the spark. 


Wow.  Your hubris is amazing.  Consummate professionals, who have direct access to the evidence, determine the plant explosion occurred without an initial spark, and yet you somehow divine they are mistaken.  Please, tell us the source of your magic power?

While you contemplate your response, bear in mind it took me fifteen seconds to find this reference... Negative Joule-Thomson coefficient; leaking gas warms and may spontaneously ignite.


Getting back on topic: The primary goal with any high risk project is to eliminate and reduce as much risk as possible.  No sane person would deliberately add more risk.  With helium available, no sane person would use a hydrogen balloon for Mr. Baumgartner's jump.

GoForSmoke

It's called knowing basic quantum mechanics and perhaps it's how you define 'spark'. What do you think happens when molecules get hot anyway? They're not billiard balls. Orbitals get high and photons do fly.

Were you there when I learned physics and chemistry through experiments?

Be sure in the legal finger-pointing sense 'spark' is usually something that comes from outside. Kind of like how around 1980 in court, 8086 code was not 8088 code though the same PCDOS ran on both.
Nick Gammon on multitasking Arduinos:
1) http://gammon.com.au/blink
2) http://gammon.com.au/serial
3) http://gammon.com.au/interrupts

cyberteque

I still think this is part of the "bad press" hydrogen got because of the Hindenburg.
Has anyone seen a documentary where a JPL engineer first put forward the theory about the Hindenburg's "skin" as a possible source of it's demise?
Canvas, doped, with iron oxide on the inside and aluminium on the outside, can anybody spell "thermite"?

People were allowed to smoke on the Hindenburg, they just were not allowed to use a naked flame to light up with.


AWOL

SlightIy OT: I  once read an essay (it may have been by Primo Levi) about not smothering a petrol (or I guess any flammable fumes or gas) leak with a CO2 extinguisher - the rush of ice crystals through the nozzle, and the drying effect on the air can cause static charges to build up and spark.
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

cyberteque

Back in high school, the fire brigade came to refill and test all the extinguishers.
One of the firemen put a few inches of water in a bucket, then gave the inside of the bucket a long burst out of a CO2 extinguisher.
Then got me to touch the surface of the water.

The big fat spark that got me REALLY hurt!!

That was when he told us about the dangers of using a CO2 extinguisher on flammable liquids, gas leak fires or fine powder fires.

This is why you won't find CO2 extinguishers in grain silo's, grain elevators or flour mills.

GoForSmoke

High pressure dry or nearly dry air (not the canned non-static mix) makes static when sprayed. It's a great way to zap, errrrr, test chips. I clean my PC with a vacuum cleaner taking care not to touch the nozzle to anything for that reason, also I'm too cheap to buy the canned stuff.

Nick Gammon on multitasking Arduinos:
1) http://gammon.com.au/blink
2) http://gammon.com.au/serial
3) http://gammon.com.au/interrupts

Riva



Joule-Thomson appear to disagree with you...
http://en.wikipedia.org/wiki/Joule%E2%80%93Thomson_effect

I have first-hand knowledge that escaping hydrogen can ignite in the way I've described.


And the lack of eyebrows to prove it   XD

focalist

If you have ever experienced a gaseous fuel-air detonation, you know why.  Preserving Helium isn't as critical as the sheer scale of forces involved.  Trust me on this one, the risks are so severe that the costs and engineering in using Helium efficiently are worth cost considering the destructive force waiting inside a Hydrogen balloon or dirigible, etc.

In addition, I hold out hope that helium production via controlled fusion is on the horizon.  That horizon may be fifty year, a hundred, or ten-  but it will happen.  I'll even hold out for Fusion as a power source.  In the final analysis, it was clear that those guys a few years back (Pons and Fleischmann I think their names were) saw SOMETHING.  Their basic idea wasn't totally crackpot, they just assumed some things were as they thought before they went public.  Be it microcavitation, or even just Tomakak-esque energy dumps on a target, we will get controlled fusion within a few decades.. I'd like to see it in my lifetime, and I think that's not only possible, but likely.  Then, we have Helium as a "waste product" of virtually unlimited energy..
When the testing is complete there will be... cake.

GoForSmoke

Could you harvest more helium from the solar wind? Fusion involves very small amounts of changed atoms for very large amounts of power.

I have a friend still alive who flew anti-sub blimps in WWII. He describes the Goodyear blimps as toys. But how many Niagara-year-power-equivalents it would take to fill one of those toys is beyond my abilities to calculate any more. IIRC it would start with ergs per He atom and proceed through Avogadro's number x 2 atoms per 4 grams of He... that's a LOT of atoms but then ergs are so small compared to the power generated, I get lost.

What's that old line about powering a city for a year on a liter of sea water?


Nick Gammon on multitasking Arduinos:
1) http://gammon.com.au/blink
2) http://gammon.com.au/serial
3) http://gammon.com.au/interrupts

AWOL

Quote
What's that old line about powering a city for a year on a liter of sea water?

Not sure, but there's a story online about the US Navy wanting to turn seawater into fuel, at a cost of about four times the cost of natural sources.
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

GoForSmoke

Does that include the cost of either coming in to base to refuel or maintaining and using ships to carry fuel in that have to go back to base to refuel? Or the strategic advantages of not having to refuel just certain ships like submarines at known ports? Because they don't have to do that for the whole fleet.

OTOH we could be green and go back to sails. ;^) Not for all the ships, just the real big ones, LOL!

The scientist holding up the beaker of water and saying this could run a city for a year or something like is an old stock cold fusion scifi line. I just forget how much it's based on numbers.

I saw a thing where Russian scientists had found at Chernobyl that some of the lead shielding had been turned to gold through radiation exposure. Not much I suppose and from what they said the gold was strongly radioactive.
Nick Gammon on multitasking Arduinos:
1) http://gammon.com.au/blink
2) http://gammon.com.au/serial
3) http://gammon.com.au/interrupts

Chagrin


SlightIy OT: I  once read an essay (it may have been by Primo Levi) about not smothering a petrol (or I guess any flammable fumes or gas) leak with a CO2 extinguisher - the rush of ice crystals through the nozzle, and the drying effect on the air can cause static charges to build up and spark.


Like the dryness of acetylene when it comes from the tank. Can be quite sensitive to static and create - surprises.

I do wonder how they managed to use hydrogen for balloons back in the day. They must have had some method of hydrating the gas when filling those blimps.

JoeN



SlightIy OT: I  once read an essay (it may have been by Primo Levi) about not smothering a petrol (or I guess any flammable fumes or gas) leak with a CO2 extinguisher - the rush of ice crystals through the nozzle, and the drying effect on the air can cause static charges to build up and spark.


Like the dryness of acetylene when it comes from the tank. Can be quite sensitive to static and create - surprises.

I do wonder how they managed to use hydrogen for balloons back in the day. They must have had some method of hydrating the gas when filling those blimps.


This reminds me of a sad story from a few years ago about a hair dresser having a large bottle of hydrogen peroxide in the passenger compartment of her vehicle which exploded and killed her, probably because of an open source of flame...

http://www.foxnews.com/world/2010/03/25/uk-teen-dies-blast-cigarette-sparks-hair-bleach/
I have only come here seeking knowledge. Things they would not teach me of in college.

cyberteque

you have to wonder what concentration her bottle of bleach was!

On the turkey farm we used "Oxonia", a mix of 33% hydrogen peroxide and 33% peracetic acid to clean, sanitise and dissolve crud in our drinker system.
That was nasty stuff, even diluted 25:1 it burnt skin and you couldn't wash it off.
The guy who owned the place set fire to a paper water filter with it!

AWOL

Quote
Like the dryness of acetylene when it comes from the tank. Can be quite sensitive to static and create - surprises.
It is sometimes hard to figure out some peoples' thought processes. "Let me think - what is it that allows me to stick a balloon to the wall, and what is it that causes my welding torch to ignite?"
Ethyne-deniers are simply Darwin Award fodder.
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

Go Up