# Overview
The vacuumFurnace case simulates the radiative heating of a steel block by a
50kW heater. After 12000s of simulated time, the heater is turned off and the
block is cooled by thermal radiation and natural convection.

# Cooling
The steel block takes a long time to cool down, due to its large thermal mass.
The "Allrun" script provides three options for accelerating the cooling stage
of the simulation:
    + frozen: calculate flow once, then calculate cooling (frozen flow)
    + periodic: calculate flow at intervals during cooling
    + continuous: calculate flow continuously while cooling
These options provide a compromise between accuracy and speed:
    + frozen (default): lower accuracy, shorter run time
    + periodic: medium accuracy, medium run time
    + continuous: higher accuracy, longer run time

# Simulation time
The "Allrun" script does not simulate the complete cooling of the block to
ambient temperature (300K). The script simulates 2000s of cooling instead,
which is sufficient to observe the differences between the cooling options.
