Simple Calculations Showing the Official 911 Story is ImpossibleSubmitted by James_Madison_Lives on Wed, 12/22/2010 - 03:27
An explanation for the intelligent layman.
The impossibility of the official story of the WTC tower collapses on 911 can be shown by a relatively simple set of calculations. These will show that the fuel required for the steel structures to reach temperatures necessary for them to weaken to the point of catastrophic failure was simply not present. Discussions over the temperatures which the fires may have reached misunderstands the concept of heat transfer. Not only must the fuel, in this case office synthetics and kerosene, burn hot enough; it must burn hot enough, long enough, and over a wide enough area to heat the steel frame to the point of failure. Steel is an excellent heat conductor. The steel frames were well-connected with extensive cross-bracing and gusset plates, allowing for efficient conduction. Thus the heat applied to the steel would have dissipated throughout the entire structure, which consisted of about 96,000 tons of steel, according to most estimates. This is similar to how if you stick one end of a crowbar into a fireplace, you will quickly feel the heat on the other end. This is heat conduction. This well-known property of steel applies regardless of scale, whether we are talking about a crowbar or the end of an I-beam over a bonfire.
Every material has a property called a specific heat, which is the energy required to raise one gram or other weight unit of that substance by one degree. Whether it is water, wood, aluminum, steel, or any other metal, these are well-known and established scientific values. Heat energy is measured in calories, joules, or BTU, which like feet and meters, are simply different ways of measuring the same thing. By definition, the energy required to raise the temperature of one gram of water by one degree is called a calorie.
Some specific heats, in British Thermal Units (BTUs required to raise one pound of substance by one degree F):
aluminum: .22 BTU/lb.
copper: .09 BTU/lb.
iron: .11 BTU/lb.
Another well-established fact of science is that different fuels have different heat contents, that is, amounts of heat energy, measured in calories, joules or BTUs which a weight unit of that fuel can deliver.
Some heat-energy content values:
wood: 7870 BTU/lb.
paper: 6500 BTU/lb.
gasoline: 19000 BTU/lb.
How much heat is actually delivered depends on how "clean" the burn is, meaning how well-supplied with oxygen and how thoroughly it combusts. The kerosene in a jet engine is atomized, that is, sprayed into the combustion chamber as an aerosol and mixed with heated, compressed air, which fires a very efficient, clean burn into carbon and water. The role of oxygen in a burn is important. Open air fires are often described as taking place under "atmospheric" or "ambient" conditions, which means the air supply consists of only what is available in the surrounding environment. This is in contrast to combustion under a forced air supply which causes any fuel to burn much hotter and faster.
Anyone who has tended a fire knows that even if a fire is dying out, if you put a new logs into the coals and stoke them with a bellows or a newspaper, the coals will glow red hot and the new log will burst into flames. This same principle is how a blast furnace generates so much heat, so named because air is "blasted" through coal or coke, in order to melt iron ore or steel. Convection currents are still considered atmospheric pressure. The idea that convection currents can provide the kind of mechanically forced air supply needed to bring steel to high temperatures is nonsense. However, we will grant the assumption in the official story that convection currents somehow "sucked" air in from the gashes in the buildings and replicated the mechanically forced air supply of a blast furnace.
Using the specific heat of steel, let us calculate the amount of energy it would require to heat the steel in the towers to 1800F, a significant temperature increase even though steel does not melt until it reaches 2700F. Again, specific heat is the energy required to raise a weight unit of a substance, like water or steel, by one degree, and steel is an excellent heat conductor. The towers contained 96,000 short tons of steel, about 35,000 of those in the strong central core, and most of the rest in the perimeter columns. The specific heat of carbon steel is .12 BTUs per pound. Doing a weight conversion from tons to pounds of steel, this means the energy required to bring this much steel to 1800F would be approximately:
1800 degrees F x .12 BTU/lb. x 192,000,000 lbs of steel = 41.5 billion BTU of energy
Much of the energy of the fuel in a blast furnace is lost to the atmosphere or heating of the interior walls of the melting chamber. The proportion of the energy in a burning fuel which is actually transferred to the target ore or scrap metal is called heat transfer efficiency. In the steel business, in a typical blast furnace, heat transfer efficiency is about 30 percent.
Burning office synthetics, acrylic carpet, composite upholstery, partitions, and computer plastics, yields a maximum of 38 million BTUs of energy per ton in an efficient, forced air burn. Therefore, if the total energy required to bring one tower's 96,000 tons of steel to 1800F is 41.5 billion BTU, and one ton of office synthetics potentially delivers 38 million BTUs, then making the very generous assumption that heat transfer efficiency in the towers approached that found inside a blast furnace, the number of tons of the office fuels needed to raise the temperature of the steel in a tower to 1800F would be:
41.5 billion BTU/(38 million BTU per ton of fuel x .30) = 3333 tons
Some of the burning material would have been paper, but paper contains less energy than plastic, about 13 million BTU/ton, versus 38 million/ton for plastic. Therefore, by assuming all the burning material was plastics, we are continuing to err on the side favorable to the official story.
The maximum amount of kerosene jet fuel which could have spilled into the buildings was about 30 tons, which was the fuel load for each flight. It is clear now that this amount of kerosene present, which also delivers a maximum of 38 million BTU/ton, comes nowhere near the more than 3000 tons of burning fuel required to raise the temperature of the steel frames this much, which is why the jet fuel is rightly dismissed as insignificant. This is also assuming every drop was retained in the buildings and none was lost in the fireballs, another generous assumption.
The fires in the WTCs were confined to a small number of floors, according to extensive survivor testimony and simple observation. However, in order to grant the assumptions most favorable to the official collapse theory, we will posit that fires were rampant across the top thirty stories of each building, the upper quarter of each. Tower One was hit at the 78th floor and Tower Two at the 92nd. Given our known energy requirement, and knowing that each floor of the Towers provided office space for an average of 136 workers, this means that the carpet etc. burning in the engulfed floors would amount to nearly 1 ton per worker of paper, computer plastic, carpet and cubicle partition, all burning in an oxygen rich, blast furnace environment, or over 120 tons of burning carpet etc. per floor.
Making the assumption fires were burning on every floor of the towers, then each of the 15,000 workers in each tower would have to account for over 400 lbs. of carpet, upholstery, and paper, all burning at maximum efficiency under a forced air supply. This would exclude the metal parts of computers like metal chassis, as well as metal file cabinets and server racks.
It is unlikely that heat was transferred from fuel to steel with anywhere near the heat transfer efficiency of a blast furnace designed for such a process, so the values arrived at here would most likely have to be doubled, tripled, or more under more realistic assumptions.
It is hard to imagine how each worker in an office can account for one ton of combustible office synthetics (again, excluding metal.) This is the weight equivalent of a Nissan Maxima parked next to every other worker. That's a lot of carpet.
Finally, one challenge which could be raised to this analysis is the assumption that such a scenario requires all the steel in the building to be heated to the same temperature in order to exhibit onset of failure characteristics. But if we discard the known fact that steel is an excellent heat conductor, and would wick the heat to all parts of the steel structure rapidly and evenly, and that the entire 96,000 tons was absorbing energy, and suppose that somehow all the heat was concentrated around the points of impact, which somehow melted or buckled only in these places, then we run across another problem. The problem with this hypothesis is that it leaves the 90% of the steel frames below the points of impact with all their strength intact, which would have made a free-fall collapse through the path of greatest resistance utterly impossible. We cannot hold that a free-fall collapse was possible because the steel in the towers was greatly weakened by the heat, then at the same time hold that the heat was focused in one place. One cannot have it both ways.
The "straw man" often used by defenders of the official story is that skeptics are claiming "fire does not melt steel," which is clearly absurd. Fire melts or makes steel malleable all the time, in a blast furnace. As always with such oversimplifications, the issue is not whether fire can melt steel, but what kind of fire, burning how hot, how long, and over what area. As we have seen, how high the temperatures may or may not have gotten is only one consideration. You can raise the temperature of the steel in a very small area to melting very quickly with the 5000F point flame of a blowtorch. But you are unlikely to take down the towers with that blowtorch. It is total energy delivered which is important.
The official account of the three towers' collapses, even Building 7 which was not hit by a jetliner, centers around the ridiculous notion that somehow the steel frames lost enough of their tensile strength through heat to become like "clay," and that the top floors where the damage was the greatest finally "buckled" and started a chain reaction in which the accumulating weight and momentum of collapsing floors forced the rest of the steel frame down. But it can be observed that even clay has a tensile strength and does not squash itself flat at free-fall speed. Moreover the "momentum" from a light body, the upper floors, cannot "plunge" through the upward static resistance of a much heavier body, the massive central core which remained largely undamaged.
In any event, the speed of such an unlikely collapse would have to be considerably slower than free-fall, to account for the resistance of the "clay." Free-fall speed could only be attained by all of the steel in the structure reaching melting point of 2800F, a condition which would require the adding of even more tons of office materials burning with the heat and efficiency of a blast furnace. The only other way for a steel frame to come down at free-fall is for it to be cut into small pieces all at once or in rapid progression, so that the remains of the structure are falling through air. This is precisely what a demolition is.
Keep in mind 1800F is far short, by about a thousand degrees, of the melting point of steel of about 2700F. Much more fuel would have been needed to raise the temperature of the frames to the melting point. Even if the steel had weakened appreciably at this temperature, and we have seen that it is unlikely that this much fuel was even available, never mind burning, on the floors on which there were fires, chief WTC engineer John Skilling said the perimeter columns alone, which were not the structures' main support (the cores were) could handle an increase in live loads of 2000% before failure.
In order to focus the argument, speculation over how the towers did come down has been deliberately placed outside the scope of this essay. Our purpose is to establish once and for all, according to the basic laws of thermodynamics, how they could not have.
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