Modifying the Simulation Type

In this step you will make the problem transient. Later, you will set the concentration of smoke to rise exponentially with time, so it is necessary to ensure that the interval between the timesteps is smaller at the beginning of the simulation than at the end.

Click Simulation Type .

Apply the following settings

Tab	Setting	Value
Basic Settings	Simulation Type > Option	Transient
	Simulation Type > Time Duration > Total Time	30 [s]
	Simulation Type > Time Steps > Timesteps^[a]^[b]	40.25, 20.5, 21.0, 132.0 [s]
	Simulation Type > Initial Time > Time	0 [s]
^[a]Do NOT click Enter Expression to enter lists of values. Enter the list without the units, then set the units in the drop-down list. ^[b]This list specifies 4 timesteps of 0.25 [s], then 2 timesteps of 0.5 [s], etc.

Click OK.