this was the first time it would be applied to the behavior of fire, but they believed it would work because heat and air flow like fluids. >> the hot air causes the fluid to expand, and it makes it lighter, and then it tends to rise relative to the other ambient fluid around. and so, then you see smoke rising, smoke plumes, and that's the kind of thing that we can simulate with the software, because it really is just simple fluid mechanics. >> but could it solve the mystery of the king's cross fire? ♪ turn around ♪ every now and then i get a little bit hungry ♪ ♪ and there's nothing good around ♪ ♪ turn around, barry ♪ i finally found the right snack ♪ [ female announcer ] fiber one. did you run into traffic? no, just had to stop by the house to grab a few things. you stopped by the house? uh-huh. yea. alright, whenever you get your stuff, run upstairs, get cleaned up for dinner. you leave the house in good shape? yea. yea, of course. ♪ [ sportscaster talking on tv ]