I don't know those details or what they were modeling. But the adiabatic flame temperature of burning jet fuel (kerosene) is easily above the melting point of steel, and far above the temperature at which structural steel loses 70% of its strength. Since that is true, what is "unrealistic"?
Why not? That is the flame temperature at which a substance burns if there is neither an excess nor a lack of oxygen for combustion (i.e., complete combustion). More oxygen does not aid the combustion but dilutes the flame temperature. (This technique of lean burning is how modern jet engines avoid melting their turbine blades. So, there is no physical problem in jet fuel burning as hot as possible.) Less oxygen leads to incomplete combustion. The burning environment was a "stove" in which the walls retained the radiation produced by the combustion process and prevented cooling. The elevator shafts may have provided adequate draft to keep the fire going.
NIST had to use unrealistic parameter values in their computer simulation to get the steel to weaken as much as they say it did.
I don't know those details or what they were modeling. But the adiabatic flame temperature of burning jet fuel (kerosene) is easily above the melting point of steel, and far above the temperature at which structural steel loses 70% of its strength. Since that is true, what is "unrealistic"?
I had to look up adiabatic. No way it burned as hot as possible, right?
Why not? That is the flame temperature at which a substance burns if there is neither an excess nor a lack of oxygen for combustion (i.e., complete combustion). More oxygen does not aid the combustion but dilutes the flame temperature. (This technique of lean burning is how modern jet engines avoid melting their turbine blades. So, there is no physical problem in jet fuel burning as hot as possible.) Less oxygen leads to incomplete combustion. The burning environment was a "stove" in which the walls retained the radiation produced by the combustion process and prevented cooling. The elevator shafts may have provided adequate draft to keep the fire going.
Here is a pretty good source for various adiabatic flame temperatures for common fuels: https://en.wikipedia.org/wiki/Adiabatic_flame_temperature (Also, look here for the flame temperature of aluminum.)
Pretty sure you have to force a ton of air to get the maximum.