Hi all, I have a system which involves a ventilated box with a heat source located inside, if the heat source inside is say 1KW and I know it eventually reaches a steady state, in an ideal world it would reach this steady state by effectively ventilating 1KW of heat through the opening and assuming the boundaries of the box were adiabatic. However, obviously in the real world this isn't the case as there will be some heat loss from the container itself, dependent on material, if the heat loss through the fabric is relatively small, say 10W, how would I account for this heat loss. I should be more clear, if I am heating a box of fluid immersed in a large reservoir of ambient fluid held at a constant 20 degrees C and I know that if the box of fluid where perfectly insulated it would heat up the fluid in the container to 25 degrees C before reaching steady state as described above, i.e. as much heat gets vented as I am putting in. How would I determine the temperature reached in the container when accounting for the heat loss from the fabric? Naively I would say that as the heat loss is 1% of the heat flux going into the container I could just say that the temperature reached would be 99% of the 25 degrees C it is expected to reach. I say naively as I am not sure this is a fair assumption at all, is it better to say that now the flux going in, the 1KW, is now being balanced by the flux going out through the vent plus the heat loss, i.e. the vent flux is now equal to 990W? Any help of guidance would be much appreciated, and I apologise in advance if this makes no sense!