04 December, 2006

Snow Heat Transfer - Inherent Control

Every time I walk through falling snow I am amazed at how effective it is at maintaining temperatures near freezing. It won’t let it stay warmer or get cooler.

It is so light and fluffy that when it contacts something warmer than freezing it instantly melts and removes just a small chunk of heat. Thousands of them quickly suck the heat out of anything.

On the opposite end the same lightness holds air and makes it a phenomenal insulator. If you have a layer of snow on your roof the heating bill is smaller. If it coats your yard early in the autumn less grass dies an you have less of a bog in the spring. The igloo relies on this.

It’s pretty amazing stuff. It is an inherent control.

When we are designing systems we should strive for that elegance.

A simple part of the system that fulfills many functions.

Update:
I like Jake's comment.

The thing that amazes me is that all of the power of a snowflake hinges on it's balance between phases. A bit of latent heat and it changes. That extra energy required for the change makes all of the difference though. An argument for the weak anthropic principle I guess.

2 comments:

Jake Brodsky said...

Ah yes. The art of engineering. Most art majors would scoff at this notion. Yet, I know I've seen elegant solutions, ordinary solutions, and a few which are brute force ugly.

There really is an art to engineering. It is as complex as a snowflake. It is as much a human endeavor as sculpture or painting. But I've yet to find an art teacher who will believe me...

DM said...

@Jake:

That's because they are all over at the architecture schools...