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Author: Subject: 4 Students Burned At Maple Grove Junior High
smuv
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[*] posted on 2-12-2011 at 21:53
4 Students Burned At Maple Grove Junior High


During a chemistry demonstration. This will be great for chemistry education.

http://minnesota.cbslocal.com/2011/12/01/3-students-burned-a...




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[*] posted on 3-12-2011 at 05:54


WTF, was it menthol or methanol? Haha. I wonder what he was trying to do and how he screwed it up so badly.



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[*] posted on 3-12-2011 at 10:50


Judging by the article, it was a whoosh bottle experiment.

And this is probably what happened, only with more liquid methanol thrown around.
<iframe sandbox width="420" height="315" src="http://www.youtube.com/embed/RNOrM8fbKxY" frameborder="0" allowfullscreen></iframe>




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[*] posted on 3-12-2011 at 12:48


Is it possible that, in the presence of air, methanol could be slowly oxidized into some some form of organic peroxide? This could potentially explain the unpredictable explosive deflagration.

For example, isopropanol is known to form organic peroxide in storage. Usually this does not present a hazard unless the isopropanol is anhydrous.
Quote:

Previously opened containers of Isopropanol (either in supplier containers or in wash bottles) tested positive for peroxides.

http://www.bnl.gov/esh/shsd/programs/Program_Area_Chemicals_...

It also appears that methyl groups are attacked much less readily than ethyl or isopropyl groups:

Quote:

studies have found that, compared to diethyl ether and diisopropyl ether, dimethyl ether formed no peroxides. Harsh conditions, ocmbined with exposure to UV light, presence of contaminants, and exposure to air, are needed to produce ant demonstratable amount of peroxide. The risk of peroxide formation from dimethyl ether under normal conditions is extremely small.

"Beyond Oil and Gas: The Methanol Economy" George A. Olah, Alain Goeppert, G. K. Surya Prakash, p225

This tendancy may likely extend to the related alcohols, in addition to the ethers.

[Edited on 3-12-2011 by AndersHoveland]
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[*] posted on 3-12-2011 at 16:43


You certainly don't need to invoke a theoretical methanol peroxide to account for this, only too much liquid methanol remaining in the bottle. The idea behind a whoosh bottle experiment (I agree with Endimion on this one) is that you are ignite a gaseous mixture of alcohol and air. Although highly energetic, it is relatively safe as long as it is isolated from other flammable materials and there is a way to control flying debris if the bottle splits. The presence of liquid methanol in the bottle makes this a much more dangerous experiment - the flying burning liquid is much worse than the gases.
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[*] posted on 3-12-2011 at 19:06


Whoosh bottle is really one of the dumbest experiments around, which becomes unbelieveably moronic if a glass bottle is used.
Such mixtures are to be ignited in narrow, thickwalled tubes, so that the forces involved are too weak.
The whole concept of the whoosh bottle is very stupid and goes against everything we know about dealing with explosive fuel-air mixtures.




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[*] posted on 3-12-2011 at 21:01


^ glad you weren't my chem teacher. you're no fun at all.



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[*] posted on 3-12-2011 at 21:02


Quote: Originally posted by Endimion17  
Whoosh bottle is really one of the dumbest experiments around, which becomes unbelieveably moronic if a glass bottle is used.
Such mixtures are to be ignited in narrow, thickwalled tubes, so that the forces involved are too weak.
The whole concept of the whoosh bottle is very stupid and goes against everything we know about dealing with explosive fuel-air mixtures.


I couldn't agree more. It defies common sense. I can see doing this with test tubes full of H2, but that's about it.

What also is incredible is that he's doing this to impress all the students, and they are standing close enough to get severely burned.

Say the whoosh had been successful. Then the students will want to go home and try this with gasoline! What a stupid demo. That instructor should be fired!




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[*] posted on 4-12-2011 at 08:26


This was on the front page of one of the <a href="http://www.startribune.com/local/west/134841058.html">local papers</a>. I fear this incident will fuel the movement to remove experimental chemistry from the classroom.
Quote:
"I'm sure he feels bad, he's obviously a teacher; he likes kids. We're not looking for blood from him," Gus Neuberger said. "But perhaps I think some policy changes and safety issues need to be addressed."

What needs to be addressed is the competence of the teachers.




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[*] posted on 4-12-2011 at 09:25


Quote: Originally posted by Rogeryermaw  
^ glad you weren't my chem teacher. you're no fun at all.


So by fun you mean exposing other people to danger and hitting another nail in the coffin of American experimental curriculum in highschools?

I did all kinds of things for students, but never idiotic things like this one.




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[*] posted on 6-1-2012 at 07:45


Peroxydes only form when there are stabilizing groups arround the Carbon atom holing the peroxo group...
Such stabilization occurs with methyl groups; the more are present, the best...remember that peroxyde formation is a radicalar reaction and stability is thus in the sequence (CH3)3C° > (CH3)2CH° >> CH3-CH2° >>> CH3°
Methanol holds no stabilizing group and so oxydation immediately produce formol, formic acid or carbonic acid.
This explains why diisopropyl ether or ditertbutyl ether forms so easily peroxydes!




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[*] posted on 6-1-2012 at 12:16


Context?



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[*] posted on 6-1-2012 at 19:27


I remember doing the woosh bottle in chem class. Except we used isopropanol in a huge plastic bottle. It was lit with a very long rod with a candle attached, outside. That's how you do the woosh bottle with out getting burned.



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[*] posted on 9-5-2018 at 15:11


I was just watching ABC news and there was another whoosh bottle goes bang I suspect as it was mentioned ethyl alcohol and boric acid. It was a first year teacher. This link doesn't mention the chemicals but the live news did. But maybe it was unsafe handling of the alcohol somehow. They never explain things coherently on the news with stories like this.
https://abcnews.go.com/US/high-school-evacuated-chemistry-cl...

[Edited on 9-5-2018 by Morgan]
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[*] posted on 9-5-2018 at 17:04


Shades of the chem teacher who poured more alcohol with colorant onto what she thought was burned out. Don't remember how many she burned, but some needed skin grafts.

Let ME do your demo involving fire, I have learned how to be safe the hardest way.

(Edit)

Damn, this was right in my neighborhood. I have fired shows in that suburb.

[Edited on 5-10-2018 by Bert]




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[*] posted on 9-5-2018 at 17:15


reading the comments is depressing, kids are taught to be gutless whiners from day one it seems.

No wonder we're int he state we are! as a kid I been shocked set on fire hit by stuff, you shake it off, get patched up and keep going, and yet they said they where all hysterical and crying and huddled? WTF?

Are schools covered in foam now days with safe spaces at every corner and crisis councilor should a finger nail break?

Only one kid has a reason to be annoyed and that's the one still in hospital the rest should be told to get a grip and continue on with a big stamp saying "Welcome to life, it doesn't get any easier from here"

This should be used as a learning event of why it is important to not panick and have a plan of action!
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[*] posted on 9-5-2018 at 17:21


Quote: Originally posted by Bert  
Shades of the chem teacher who poured more alcohol with colorant onto what she thought was burned out. Don't remember how many she burned, but some needed skin grafts.

Let ME do your demo involving fire, I have learned how to be safe the hardest way.


this comes back to lack of exposure to life, too many people are retarded from being too coddled, so they lack the ability to think through situations and possible out comes and to accurately asses risk.

It is a feed back loop too and it needs to be broken imo, but we'll see more banning of activities, that will just make people even more retarded in their abilities, and more bans and well Idiocrisy was meant to be a comedy, little did they know they where foretelling the future!

It is harder to train an adult when they have not gained this ability as a child to appreciate the gravity of certain situations.

Don't get me wrong getting burned sucks, I been set on fire due to engine malfunction, but unless it is actually serious, it should be treated as the inconvenience it is, Vs perpetuating the poor me victim culture that is all the craze.

I hope they all make speedy problem free recoveries, annoying thing with burns is they tend to scare more so then other injuries, ate least at their age they will be very un noticable if it happens.

[Edited on 10-5-2018 by XeonTheMGPony]
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[*] posted on 9-5-2018 at 18:41


What descriptive skills ... but a few crumbs the other article didn't have.
"Bush said the students were gathered around as the teacher did a demonstration that involved mixing chemicals."
"There was a sudden flash fire lasting 3 – 5 seconds. Because there was no smoke it did not set off any fire alarms."
So why was the whole school evacuated?
"Nicholls said they had superficial burns on their arms from the chemical reaction caused by mixing boric acid and ethyl alcohol, which produces a small flame." Oh!
http://www.wkrn.com/top-news/merrol-hyde-magnet-school-evacu...
Also in the long audio, the dry chemical fire extinguisher if gotten in the eyes or on the skin could have become an irritant.

[Edited on 10-5-2018 by Morgan]
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[*] posted on 9-5-2018 at 19:39


Reminds me of a similar incident in 2006, where a methanol fire/explosion injured school students: https://www.youtube.com/watch?v=g6vR0BdRCNY



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[*] posted on 9-5-2018 at 19:49


I see what you're saying, Xeon, about "lack of exposure to life." Perhaps, if the teacher had taken more risks as a kid, maybe played with fire a little, he would understand how to manage these risks in the future. Also, the students maybe would have reacted less emotionally to the incident if our society was different. I don't know, some people are just by nature more easily disturbed. Going into hysterics AFTER a painful and frightening event will not cause any harm whatsoever. Now if it interferes with them managing the accident (e.g. putting out a fire, exiting the building, etc.) in the middle of it, then that is a problem, although I doubt we can change these personality traits by avoiding "coddling" and "victim mentality". Also, the first link Morgan gave only showed four comments, and none were by people who were at the accident, or who talked about children crying and huddling. Did you get some other source of information? Maybe it told more?

What really confuses me is what chemicals ignited, and what the damage was like. For ethyl alcohol, I'd expect something either like the accident Bert described with a bottle of alcohol poured right into a flame , or else a whoosh bottle with way too much fuel in it. Either way, the vapors could ignite and expand, pushing some liquid out of the bottle. To hurt 18 people, and to have to evacuate the building due to fumes, I'd assume the amount of fuel expelled was way more than this or this, but still less than this. Sorry for all the links; I guess that real life can be like an unrealistically explosion-filled Hollywood movie once in a while.:D:P

But, all these people got admitted to the hospital, but didn't have to stay there? That means they got burned significantly, but not catastrophically like someone in a room covered by flammable liquid. Perhaps a layer of vapor gathered along the floor, and just ignited in a flash? Also, they say they had "chemical burns?" Would boric acid/triethyl borate in ethanol really be corrosive to skin, or do they just mean "burns from flaming lab chemicals." Perhaps they will have more details later.

Edit: I walked away from the keyboard for about an hour before posting this, and didn't realize other people had replied. It sounds like they were probably going to make a colored flame, just like in the accident DavidJr linked to. Why it made a flash fire? Could have been vapors, a spill, an explosion inside the bottle, or something else entirely. Good point, Morgan, that some of the injuries (and the evacuation of the whole building) could have been from having to use a fire extinguisher in a packed classroom.


[Edited on 10-5-2018 by Vomaturge]
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[*] posted on 10-5-2018 at 04:25


Goat that video was horribal every thing don wrong! this is what I mean people are so badly ignorant about basic things in life due to lack of experience and teaching, had she laid down and the guy used his shirt to protect her face while waiter grabbed towel she'd been out in no time.

To every one here: If a fire ever flashes, STOP, think, then act never react! Calmly get a towel do not run, if time allows moisten it, lay it on the wire do not wave it like the guy did in the video, add more towels as necessary, can be a cloth blanket even.

and if you are on fire, first protect head, then drop and roll, or if you planed things properly get in the shower! First thing that should be in your lab if you handle flammable solvents.

https://www.youtube.com/watch?v=KBvMPAQHi50

If that happens kill power immediately and get every one as far away as possible as the out come is up to fate! hope to hell the gas just vents off to the wild!
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[*] posted on 10-5-2018 at 06:13


I recall a similar effect that might have occurred at the high school - a variation on a theme.
There's a drink called a flaming hurricane they used to make at Seville Quarter in my town popular during approaching hurricanes where 151 rum or Everclear is poured on the top of the drink and lit. One time the bottle of alcohol ignited ejecting the liquor lighting the bar and a few patrons on fire, thus the drink was discontinued at this locale.
https://www.agardenersforum.com/forum/ubbthreads.php/topics/...

When I was making sideways running jam jar jet snorkelers, it was important to angle the jet up enough so that the alcohol wasn't ejected like a flame thrower on the initial energetic first whoosh.
https://youtube.com/watch?v=ChtLqS7tRyo

Another possibility is that if a whoosh bottle was used it could have been weakened by too many previous demos. Also if you spark start or initiate the flame front from inside the bottle it's way more likely to go bang instead of whoosh.
And conceivably static electricity could have ignited the ethanol when pouring it. I once thought about making a Kelvin water dropper using methanol instead of water, in such a way as to light itself on fire merely by falling as droplets into a container, perhaps even starting up a jam jar jet this way.

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[*] posted on 10-5-2018 at 08:27


Yes, that one:

https://youtu.be/g6vR0BdRCNY

That's the one I was recalling.

Asside from the basic stupidity of pouring more liquid fuel onto a fire, and having a needlessly large GALLON size jug in the near vicinity of a flame at all? Let alone OPEN in her hands next to several fires? Teacher mentioning possibility of the accident, then going ahead and DOING IT ANNYWAY?!

This (alleged) chemistry teacher did the demo indoors but not in the hood. When you burn methanol inefficiently (as it is in this demo), you release some FORMALDEHYDE. Additionally, the methyl borate generated in the green flame is not benign, I would bet this teacher had no clue regarding toxicity aspects of what she was trying to do.

Attachment: Methanol Fuel Safety - A Practical Guide.pdf (182kB)
This file has been downloaded 290 times

Thise who don't learn history are doomed to repeat it?

I have a collection of events where science teachers injured (and occasionally killed) students watching their demos involving fire and energetic materials. The WiZ (Donald Haarmann) also collected these, there are some posted on this forum.

The typical attitude of the teachers involved, trained in chemistry but NOT experienced with EM (or in basic safety related to their subject?) Seems to be : I have a degree in science! I know all about this chemistry!! That equals knowing exactly what I'm doing with this here explosive!!!

Then they do something showing themselves to be utterly ignorant of the potential consequences, such as a demo on chlorate & red Phosphorus where they try to grind several GRAMS in a porcelain mortar to demonstrate the reaction. They read about that one somewhere, sounded really cool. Boy, will they ever get the student's attention. Having splinters of porcelain blown into your face and eyes will do that-

Chemistry teacher Loren Bailey said Taylor was apparently mixing red phosphorus and potassium chlorate.

Quote: Originally posted by The WiZard is In  
LIQUEFIED AIR EXPLODES
Prof. Fay Mixed It with Red Phosphorus, with Startling Result
He And A Student Injured
New York Times, October 22, 1898.


Experiment Took Place at the Polytechnic Institute, and Explosion
Luckily Was Downward.**

Experiments with liquefied air in the laboratory of the Polytechnic Institute
Brooklyn, yesterday afternoon ended in an explosion which tore a hole through
the table, knocked out same panes of glass,: and severely injured the professor
in charge. The experiments tried yesterday In the Polytechnic Institute by Prof.
Irving W. Fay are entirely new. It was in trying the effect of mixing liquefied air
with red phosphorus that the explosion was brought about. Prof. Fay will
probably lose the sight of one eye and. will always bear the marks of the
explosion on his face. Lincoln Burrows, a student, was also burned about the
face, but not severely.

Four gallons of liquefied air were taken to the institute on Thursday
afternoon. Yesterday afternoon Prof. Fay, who is the head of the chemistry
department, lectured before the Chemical Society, composed of students in the
institute, and illustrated his lecture by some familiar experiments. When the
lecture ended, half a dozen of the students remained to observe. the professor
try some original experiments. Kerosene, alcohol, and turpentine were among
the objects experimented with, and they wore frozen by the application of the
liquid air. Then yellow phosphorus was taken up. The professor placed it to a.
glass beaker and poured some of the liquid air upon it. The effect was to change
the phosphorus to crystal in structure.**

The professor then determined to try red phosphorus. Red phosphorus has
al ways been held to be indissoluble, and it was the professor's idea that possibly
liquid air might dissolve It. He accordingly placed some of it to the beaker and
poured air upon it. He then poured the mixture on a piece of paper on the table
and bent over it to observe the result. His pupils also bent over it to study it, and
wait for his comments, but were not so near it as he. Burrows was by his side.
The liquid air rapidly evaporates, and in a very short time there was nothing on
the paper but a little pile of red phosphorus. The professor and students examined
it eagerly to note the changes
produced. After a moment he called their attention to the fact that the
phosphorus was a lighter shade of red. He thought at first that the combination
might have changed it to yellow phosphorus, but a further examination led him
to believe that it had became CO2 solid carbon dioxide. [?]

While making these comments the professor stirred the he phosphorus with
a glass rod. Suddenly there was a terrific explosion. The table rocked and shook,
the room was filled with smoke, and the ease in the windows were shattered.
The professor gave a cry of pain and clapped his hand to his eyes. His face had
been torn and burned and his thumb nail torn completely off. The explosion was
a downward one, fortunately for the professor and his pupil and it tore a great
jagged hole In the table. But for the nearness of Dr. Fay’s face to the
phosphorus he would probably have escaped without serious Injury.
Dr. Henry L. Cochran of 141 Clinton Street was hurriedly sent for by his
father Dr. David H. Cochran, who is the President of the Institute. Prof. Fay was
removed to his home, 544 Ninth Street. Burrows's injuries were so slight that he
was able to go home without assistance, after having his wounds dressed by the
doctor. Dr. Arthur Mathewson, an eye and ear specialist, was called In to attend
Prof, Fay at his home.

The cause of the explosion is a question as yet. The theory held by some
of those who witnessed it is that after evaporating the air broke up into atoms,
which combined with the atoms of phosphorus, thereby causing the explosion.


* Explosions don’t “happen downward” they expand in every direction.

** My theory – The BP of LN2 is lower than that of LOX, therefore, as the
nitrogen evaporated the mixture became oxygen rich, the super cold phosphorus
and remaining LOX and coming into intimate contact.


http://www.dailyfreeman.com/article/DF/20100120/NEWS/3012099...

And on, and on.


[Edited on 5-10-2018 by Bert]

[Edited on 5-10-2018 by Bert]




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[*] posted on 11-5-2018 at 08:01


That BBQ accident that leaves girl engulfed in flames was horrific. I hadn't seen that clip before. I guess it's an often mistake pouring flammable liquids out of bottles near a flame or hot surface.
It brings to mind something I discovered by accident. I used to build these jam jar jet snorkelers using paintball tanks with plumbing pipe threaded into them to increase the thrust. Invariably they eventually stop, either because the methanol becomes watery or the tank gets too hot throwing off the fuel/air ratio. So there's always fuel left in the tank when they stop. But the thick aluminum paintball tank and snorkel gets so hot that the remaining fuel evaporates such that you can relight the top of the snorkel, the bottle becomes a candle or torch flame of sorts, sometimes the flame 25 cm or so. So as the flame subsided one day, I tilted the bottle to pour out the fuel while the flame was still going. (Even with a leather glove the bottle is almost too hot to hold.)
There was a considerable amount of thrust as the methanol flashed to steam in the hot exhaust tube or snorkel. Not only that but I found that if you did that tilting the bottle sideways instead of downward, the paintball tank would shoot an audible fireball downrange about 5 meters long. The effect was rather exhilarating.
This particular tank with an extra long snorkel was more fussy to get running but when it did the longer snorkel also produced the best effect. To feel the heatwave and see the huge bright blast of fire so suddenly, all gone in an instant seemed phenomenal for so little fuel.
http://www.pulse-jets.com/phpbb3/download/file.php?id=14852&...
http://www.pulse-jets.com/phpbb3/download/file.php?id=14851&...


[Edited on 11-5-2018 by Morgan]
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[*] posted on 11-5-2018 at 10:09




As I mentioned, I learned the hard way about a lot of energetics and fire related safety. And I'm still learning.

When I was 12 or so, I was sent out to light the charcoal grill while my parents got the rest of our dinner ready.

The charcoal lighter fluid (deodorized kerosene) was in a gallon sized metal can with a plastic insert having only a small hole (1/8" perhaps? I never measured) as a flow control set into the neck under the screw down cap. I used just about the last of it, lit the grill and went away.

About 15 minutes later, I walked past the grill and darn, the charcoal had not lit. So, I picked up the nearly empty can of charcoal lighter and upended it over the grill- Which rewarded me with a bit of a fireball, since it HAD lit, down at the bottom of the pile of charcoal.

No injuries yet, it just surprised me.

I backed away, looked at the now vigorously flaming charcoal, lowered the can and started to walk away. Of course, the can had some drops of fluid on top which were now burning, I didn't notice- Until the fuel vapors inside the can lit.

The can didn't rupture. But the plastic insert inside shot out at a pretty high speed, it hit me in the last joint of my right thumb and bruised it, my thumb nail turned purple and fell off a couple of days afterwards. The "whoosh bottle" effect flame shooting out the neck of the can burned the hairs off my forearm, leaving me with a first degree burn about 10" long and perhaps 3" wide. Lime a bad sun burn, almost no blistering, but the skin peeled off a while later.

Spent the rest of the day with my arm in a bucket of cold water, listening to my parents telling me I was an idiot, I had been repeatedly told not to do that.

The kids up the street did something similar with an unauthorized "campfire" and a can of gasoline. That ended with one of them in the burn ward for skin grafts and a neighbor's tool shed burned down.

Liquid and gaseous fuels scare me more than commercial or military solid high explosives. The explosives stay right where you put them and don't usually detonate from fire or impact. Fuels leak, off gas or otherwise escape and go looking for an ignition source.




Rapopart’s Rules for critical commentary:

1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.

Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).

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