[bigben2k]

Still waiting on the relays.


I calculated the needed power as follows:
The knowns:
-typical cfm of an 80 mm fan: 35
-density of air: 1.2 kg / m^3
-heat capacity of air: 1004 Joules / kg
-1 Watt/hour = 3600 Joules

I then calculate the needed power to be 20 Watts. 19.9 actually, but this is a rough estimate, as it doesn't account for barometric pressure, heat transfer resistance, secondary losses, or actual airflow rate.

As I mentionned before, the target is 50% duty cycle, so I'll setup the nichrome wire to apply 40 Watts at full load.

Using one foot of 30 gauge nichrome wire, and applying 2.5 amps would result in a voltage of 16.3 V. This would result in a wire temperature of ~760 deg C.

Using one foot of 33 gauge nichrome wire, and applying 1.8 amps would result in a voltage of 23 V. This would result in a wire temperature of ~870 deg C.

Both temps are within the maximum specs for these wires.

The numbers don't feel right, so I'll double check them again.

I have yet to figure out a mounting solution for this wire, but I've determined that I can use screw terminals to connect it, as long as the screw terminal isn't cheap plastic.