Time changing boundary condition
 

Hello guys

I have to run a transient simulation in which one of the boundary is radiation source and the radiation intensity id time dependent, its something like this..

Time
from to radiation
09:00 10:00 40 Wm-2
10:00 11:00 180 Wm-2
11:00 12:00 350Wm-2
12:00 13:00 340 Wm-2
13:00 14:00 370 Wm-2
14:00 15:00 290 Wm-2
15:00 16:00 400 Wm-2
16:00 17:00 390 Wm-2
17:00 18:00 250 Wm-2
18:00 19:00 70 Wm-2

i created a function "Rad" with argument as time (mins) and value as radiation... somewhat like:
2 40
62 180
122 350 and so on....
and then a expression called "Radiation" with value "Rad(Time Step)" the transient simulation has to runs for 10 hr time period with 4 min time step.
im not sure if i have done it correctly..... can anyone tell me is it correct, nad if not then please advise

Sounds OK. Or you can skip the Radiation expression bit and make the radiation condition at the boundary simply defined as rad(t).

Not sure about your definition of Rad(Tiem Step) - shouldn't this be Rad(t), that is of time?