Scientific Theory for Controlled Demo Thread.

[sunflower]

Jet Fuel Made the WTC Fires Cooler

People assume that the jet fuel which ignited the fires in the Twin Towers made the fires quite hot. However, Thomas Eager, a Professor of Materials Engineering and Engineering Systems at MIT and a defender of the official story explains that the jet fuel actually made the fires cooler:

" . . . the fact that there were 90,000 L of jet fuel on a few floors of the WTC does not mean that this was an unusually hot fire. The temperature of the fire at the WTC was not unusual . . . .

In combustion science, there are three basic types of flames, namely, a jet burner, a pre-mixed flame, and a diffuse flame. A jet burner generally involves mixing the fuel and the oxidant in nearly stoichiometric proportions and igniting the mixture in a constant-volume chamber. Since the combustion products cannot expand in the constant-volume chamber, they exit the chamber as a very high velocity, fully combusted, jet. This is what occurs in a jet engine, and this is the flame type that generates the most intense heat.

In a pre-mixed flame, the same nearly stoichiometric mixture is ignited as it exits a nozzle, under constant pressure conditions. It does not attain the flame velocities of a jet burner. An oxyacetylene torch or a Bunsen burner is a pre-mixed flame.

In a diffuse flame, the fuel and the oxidant are not mixed before ignition, but flow together in an uncontrolled manner and combust when the fuel/oxidant ratios reach values within the flammable range. A fireplace flame is a diffuse flame burning in air, as was the WTC fire.

Diffuse flames generate the lowest heat intensities of the three flame types.

If the fuel and the oxidant start at ambient temperature, a maximum flame temperature can be defined. For carbon burning in pure oxygen, the maximum is 3,200°C; for hydrogen it is 2,750°C. Thus, for virtually any hydrocarbons, the maximum flame temperature, starting at ambient temperature and using pure oxygen, is approximately 3,000°C.

This maximum flame temperature is reduced by two-thirds if air is used rather than pure oxygen. The reason is that every molecule of oxygen releases the heat of formation of a molecule of carbon monoxide and a molecule of water. If pure oxygen is used, this heat only needs to heat two molecules (carbon monoxide and water), while with air, these two molecules must be heated plus four molecules of nitrogen. Thus, burning hydrocarbons in air produces only one-third the temperature increase as burning in pure oxygen because three times as many molecules must be heated when air is used. The maximum flame temperature increase for burning hydrocarbons (jet fuel) in air is, thus, about 1,000°C—hardly sufficient to melt steel at 1,500°C.

But it is very difficult to reach this maximum temperature with a diffuse flame. There is nothing to ensure that the fuel and air in a diffuse flame are mixed in the best ratio. Typically, diffuse flames are fuel rich, meaning that the excess fuel molecules, which are unburned, must also be heated. It is known that most diffuse fires are fuel rich because blowing on a campfire or using a blacksmith’s bellows increases the rate of combustion by adding more oxygen. This fuel-rich diffuse flame can drop the temperature by up to a factor of two again. This is why the temperatures in a residential fire are usually in the 500°C to 650°C range. It is known that the WTC fire was a fuel-rich, diffuse flame as evidenced by the copious black smoke. Soot is generated by incompletely burned fuel; hence, the WTC fire was fuel rich—hardly surprising with 90,000 L of jet fuel available. Factors such as flame volume and quantity of soot decrease the radiative heat loss in the fire, moving the temperature closer to the maximum of 1,000°C. However, it is highly unlikely that the steel at the WTC experienced temperatures above the 750–800°C range."

Obviously, the jet fuel was a source of fuel, and so contributed to the ignition and spreading of the fire in the first place. However, there was actually very little jet fuel in the overall scheme of things. Moreover, that jet fuel and office supplies were the sources of fuel for the fire almost guaranteed that it would be a fuel-rich, diffuse-flame fire, which burns cool.

While the title may be slightly flip, the purpose of this essay is merely to show that jet fuel -- contrary to most people's assumption -- would not have created a hot fire. http://georgewashington.blogspot.com...emolition.html

Finally, it is true that the soot from the jet fuel and other burning hydrocarbons may have raised the temperature somewhat. However, as Professor Eager points out, the fact that it was a fuel-rich fire -- at least while the jet fuel was still burning -- decreased the temperature of the fire "by a factor up to two", which would more than offset the increase due to reduction of radiative heat loss. Again, the bottom line is that the WTC fires were not very hot.

http://georgewashington.blogspot.com...es-cooler.html

[slowhand]

Originally Posted by Duvidoo

WTF is THE scientific method? Practically every discovery in the field of science came from thinking outside the box. So why box oneself in with pre-9/11 thought processes. Did you hate all Muslims before 9/11? Did you imagine of hijacking planes with box cutters before 9/11? Did you imagine airplanes smashing into buildings and watching them tumble down into dust beforte 9/11? If you did, then you are either clairvoyant or a believer in the Dark Arts ... neither if which are terribly scientific. Try and use all that as a signature.

What scientific method?..The one that hasnt changed since the beginning of time

For example..Free fall speed, is still free fall speed

The law of gravity hasnt changed

The statute of limitations doesnt run out on these kinds of things

[slowhand]

Originally Posted by Denie

In other words, don't point out your BS...
Got it...thanks for the handy tip!!

Im arrogant..and you are obnoxious

Nice to meet you!..

[slowhand]

Originally Posted by Denie

Just curious...is this the kind of discussion I'm to learn how to have? You must be the "poster boy" for discussion etiquette being you seem to lecture on it.


I'll try to follow your example...

Obnoxious..@#%&$%^#!!!!!!!!!!..Arrogant..@#%&%*%#% ^!!!!!!!!!!!!..Fucking!!!!!!!!!..@%$^&$$&&!!!!!!!!

How am I doing Denie?..

[Duvidoo]

Originally Posted by Denie

Really? WOW...Now, name one scientist that doesn't adhere to the scientific method. These are the one's that made "every discovery in the field of science" right?

Quite funny that you have no idea what the scientific method is, yet suggest that these discoveries came as a result of not adhering the scientific method.
Mind-boggling it is!!!

One can "think outside of the box" and adhere to the scientific method. Ironic, isn't it!!!

I don't quite see what science has to do with what befell the World Trade Center on 9/11. Physics, yes. Science? Can't see it.

[Duvidoo]

Originally Posted by Denie

In other words, don't point out your BS...
Got it...thanks for the handy tip!!

Wow! The science expert has learned how to use emoticons.
What a prize twerp. Where are your goons tonight?

[brian_wilbanks]

Originally Posted by Duvidoo

I don't quite see what science has to do with what befell the World Trade Center on 9/11. Physics, yes. Science? Can't see it.

Jesus H Christ.....Physics IS science.

[Duvidoo]

Originally Posted by brian_wilbanks

Jesus H Christ.....Physics IS science.

I hated science in high school
and I'm damned if I'm going
to get more of that shit here.
Bye.

[slowhand]

Originally Posted by Duvidoo

I hated science in high school
and I'm damned if I'm going
to get more of that shit here.
Bye.

Huh..How do ya like that?..He was blinded by science..

[White Rabbit]