Aw crap! I was reading the damn thing backwards. I go now to hang my head in shame and embarrassment
johnstreet said:Another aspect to airflow is tendency of air to flow in channels. The air really sticks to the walls in my 2.5'x2'x6' cab - the temperature on the wall is 22c but 27c over middle of bud canopy. I must point out that the cooltube inlet is quite close to the wall due to being in small box.
I've tried to point passive inlets away from walls but it looks like it'll need an active circulation fan. Anyway the situation highlights how careful you have to be with measuring heat.
Another aspect to airflow, I'll venture, is that it has limit on ability to cool when excessive watts are in a small volume - I've found increasing the volume of cabinet had a dramatic effect on lowering temps and is another variable that should be considered when forecasting temps (over light watts and fan cfm alone) such as with this formula CFM= (1.78xWatt)/DiffC or CFM = (3.2 x Watt)/Diff F