by SpillsMostOfIt » Wednesday Jan 03, 2007 10:05 pm
It is all with 'found objects'...
IBM ThinkPad power supply brick,
33W Peltier device from Jaycar (the TP PS supplies about 35W, so a bigger one is no good for me),
Some big old heatsink I had laying around for decades,
Some heatsink grease,
A 12Volt computer fan.
Some thick aluminium bar.
I started out strapping it to the outside of a fermenter-like object full of water and otherwise enclosed in a wetsuit. It didn't quite work. I suspect that the rig is capable of moving a bit of heat, but just couldn't get it out of the fermenter clone due to 'transmission issues'.
I'm now looking at bolting a heatsink and fan to the cold side of the rig and mounting it in/on an esky-like device (initially a cardboard box and some closed-cell foam and/or whatever comes to hand), thus making a crappy fridge.
I've got a microcontroller and thermistor acting as a 'storage thermometer' which I have calibrated against an alcohol thermometer and can use to switch the Peltier on/off or change direction.
I've a mate who owns a Peltier fridge which can bring four litres of water from 18C to 4C in four hours and figure I must be able to get some measurable fraction of this...
Tomorrow is 'Do Something with a Cardboard Box' day.
No Mash Tun. No Chill.
No confirmed fatalities.