Re: Temperature all'interno delle torri e comportamento dell'acciaio in generale
Inviato da DrHouse il 28/7/2013 15:47:38
Citazione:
The fire is the most misunderstood part of the WTC collapse. Even today, the media report (and many scientists believe) that the steel melted. It is argued that the jet fuel burns very hot, especially with so much fuel present. This is not true. Part of the problem is that people (including engineers) often confuse temperature and heat. While they are related, they are not the same. Thermodynamically, the heat contained in a material is related to the temperature through the heat capacity and the density (or mass). Temperature is defined as an intensive property, meaning that it does not vary with the quantity of material, while the heat is an extensive property, which does vary with the amount of material. One way to distinguish the two is to note that if a second log is added to the fireplace, the temperature does not double; it stays roughly the same, but the size of the fire or the length of time the fire burns, or a combination of the two, doubles. Thus, 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, and it was most definitely not capable of melting steel.
Thomas W. Eagar, JOM, 2001
Non che te lo leggerai mai, ma anch'io ci tenevo a mettere in evidenza alcuni punti da tramandare ai posteri.
piedone70 ha scritto:
@dr house
dici riferito a me:
Finora tu hai portato 0 prove empiriche e tutte le tue argomentazioni teoriche sono state smontate, e questo principalmente per il fatto che continui a fare confusione tra temperatura e calore, il che inficia fatalmente ogni tua conclusione successiva.
QUESTA LA METTO IN EVIDENZA, SEMPRE IN AUSILIO VERSO CHI VUOLE APPROFONDIRE LA MATERIA...
The fire is the most misunderstood part of the WTC collapse. Even today, the media report (and many scientists believe) that the steel melted. It is argued that the jet fuel burns very hot, especially with so much fuel present. This is not true. Part of the problem is that people (including engineers) often confuse temperature and heat. While they are related, they are not the same. Thermodynamically, the heat contained in a material is related to the temperature through the heat capacity and the density (or mass). Temperature is defined as an intensive property, meaning that it does not vary with the quantity of material, while the heat is an extensive property, which does vary with the amount of material. One way to distinguish the two is to note that if a second log is added to the fireplace, the temperature does not double; it stays roughly the same, but the size of the fire or the length of time the fire burns, or a combination of the two, doubles. Thus, 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, and it was most definitely not capable of melting steel.
Thomas W. Eagar, JOM, 2001
Non che te lo leggerai mai, ma anch'io ci tenevo a mettere in evidenza alcuni punti da tramandare ai posteri.
Messaggio orinale: https://old.luogocomune.net/site/newbb/viewtopic.php?forum=4&topic_id=7462&post_id=239022