Agree, you need to quote your source.
It is not polite to steal other people's work without attribution. For all we know, you are taking it out of context. (
Addendum: As others have noted, the source material can be found
here. All quotes below are taken from that message. The author has chosen a pseudonym.)
While we're waiting for that, there are a number of amateur oversimplifications in this derivation that need to be corrected. Still, I appreciate the unknown author showing some math for a change -- this is head and shoulders above the usual
"but I know what it should look like" crap typical of WTC deniers. Because the math is shown, it is easy to see where they went wrong, and together we can make some progress.
As I've posted before, a good baseline paper is
"Why Did the World Trade Center Collapse? Science, Engineering, and Speculation,", Eagar and Musso, JOM, 53 (12) (2001), pp. 8-11, readable online here:
http://www.tms.org/pubs/journals/JOM/0112/Eagar/Eagar-0112.html
Now, let's pick this apart.
Unknown Source said:
What we propose to do, is to pretend that the entire 10,000 gallons of jet fuel was injected into just one floor of the World Trade Center, that the jet fuel burnt with the perfect quantity of oxygen, that no hot gases left this floor and that no heat escaped this floor by conduction.
One can find much better estimates of the actual fuel present, since the amount put on the plane was logged... No matter, laziness on the author's part does not change the final outcome.
Since we do not know the exact quantities of oxygen available to the fire, we will assume that the combustion was perfectly efficient, that is, the entire quantity of jet fuel burnt via reaction (1), even though we know that this was not so. This generous assumption will give a temperature that we know will be higher than the actual temperature of the fire attributable to the jet fuel.
You'll notice in my reference that it is accepted that the fire was not optimal, and burned quite a bit cooler than it could have under ideal conditions. This is not news, but the author is correct in pointing this out.
That is, we need to calculate the energy needed to raise:
39,857 kilograms of water vapor to the temperature T° C,
97,429 kilograms of carbon dioxide to the temperature T° C,
349,680 kilograms of nitrogen to the temperature T° C,
500,000 kilograms of steel to the temperature T° C,
1,400,000 kilograms of concrete to the temperature T° C.
And here it falls apart. The author is assuming that the
entire floor had to be heated to some particular temperature. Wrong! The heating was uneven. In fact, if you check my source, the uneven heating was one of the major contributors of the collapse.
Because the fire wasn't even, the author of your piece has grossly overestimated the thermal inertia of the affected materials. The estimate is therefore invalid.
So, if we assume a typical office fire at the WTC, then the jet fuel could have only added 280 - 25 = 255° C (at the very most) to the temperature of the fire. [...]
We have found that it is impossible the jet fuel, by itself, raised the temperature of this floor beyond 280° C (536° F).
These two paragraphs, only a few lines apart, are inconsistent. Off the top of my head, I would buy that the jet fuel might only add 250 C or so to an "ordinary" (fully involved, engulfing everything on several floors) office fire... but that "ordinary" office fire is plenty hot on its own. So, say, 250 C added to a baseline of
several hundred degrees C. I'd buy that.
But in the summary paragraph, the baseline office fire is forgotten. The jet fuel
by itself might not have, but it
wasn't by itself, nor did it have to heat the entire solid mass of the floor. So the summary conclusion is irrelevant to the real problem.
We all accept that the fire temperature was sub-700 C or so, even at its hottest parts. This derivation hasn't proven otherwise.
And now in the final act, the agenda becomes clear:
It is not even close to the first critical temperature of 600° C (1,100° F) where steel loses about half its strength and it is nowhere near the quotes of 1500° C that we constantly read about in our lying media.
"In the mid-1990s British Steel and the Building Research Establishment performed a series of six experiments at Cardington to investigate the behavior of steel frame buildings. These experiments were conducted in a simulated, eight-story building. Secondary steel beams were not protected. Despite the temperature of the steel beams reaching 800-900° C (1,500-1,700° F) in three of the tests (well above the traditionally assumed critical temperature of 600° C (1,100° F), no collapse was observed in any of the six experiments."
Quote from the FEMA report (Appendix A).
So, once again, you have been lied to by the media, are you surprised?
I haven't seen a legitimate article that claimed "1500° C," nor was such a temperature necessary. The author needs to substantiate that the "lying media" in fact lied.
The Cardington experiments may or may not have been at all relevant to the WTC situation. I can build a steel structure that won't collapse even at much higher temperatures, say if I'm building a bank vault -- does that mean that
all steel buildings should withstand that kind of treatment? Absolutely not.
So in conclusion, this analysis is flawed, and it is easy to see where and why. I would prefer to respond to the original author, but you would have prevented me from doing so.
ETA: Added link to original article, now that it has been found.
