The difference starts out at the higher value at the beginning of the draw and decreases toward the lower value as the draw proceeds because the simplified calculated buried pipe UA values are time-dependent as the sand heats
At the same time, sand heated
to 1,500[degrees]F was delivered into the gasifier, to form a fluidized bed of material that distributes heat throughout the biomass.
The bird in question is the maleo, a chicken-sized bird that lays its eggs in sand heated
by either the sun or volcanism that occurs in its habitat on the island of Sulawesi.
That is, of the 325 lb of system sand heated
to 1180F, 10% of it is bentonite that has become dead clay.