|View single post by Tramcar Trev|
|Posted: Wed Feb 18th, 2015 02:50 am||
|Herb Kephart wrote:
The 80 - 90% efficiency means that 10 - 20% of the supplied current is dissipated as heat. Some of the ads you will notice offer ''heat sinks''. These keep the chip cooler and in marginal cases may eliminate thermal shut down.
We can have a really heated debate here Herb. While I agree that a cool chip is a happy chip I beg to differ on painting the heatsink. When I was involved with some students building an electric car the university did tests on the efficiency of heatsinks. Black anodising came out with the best performance followed by natural grit blasted aluminium then "mill finish" aluminium and last painted Aluminium, the single coat of paint acted as an insulator because at the interface between the paint and the heatsink there was a layer of air. Grit blasting increased the surface area by a staggering 30% over a finely machined surface... Generally the more surface area you can get the easier it is for the heatsink to dissipate the heat ergo slim people suffer the effects of heat more than portly built people...
There once was a man who said Damn!!
I perceive with regret that I am
A creature that moves
in predestinate groves
I'm not a Bus, I'm a tram