John K's lid peltier cooling system finally finished
ALL Finished and have started testing!!!
got it all wired up tonight with a computer power supply.
Put the unit on top of a normal esky ( to mimic the JMI torus ), it was not perfectly sealed by any means. Threw a thermometer in at 20 degrees, within 10 minutes, the ambient air was 16 degrees.
There were air gaps, but if John has a better seal on your telescope, which i think he does, then I reckon the ambient can get to 5+ degrees below ambient. Hence his mirror should follow suit albeit at a slower rate.
I have very messy cabling as I reckon within a few months we will have a sensor driven unit that can slow the unit from cooling too much ie once the mirror is below say .5 of ambient, then shut the cooling off.
It is a bit of a pain in the ass when the mirror is 2 degrees below ambient and you have negative boundary layer issues. The peltier system can be reversed to heat the air, but........
I will take some pics tomorrow and get it in a box and send it to John
must say i am happy with how well it cools
dave p
|