Wind chill and frozen pipes again

[Gordon Shumway]

One would think that with a growing number of voices in opposition to your "science" that there may be a chance you have it wrong.

[krw]

Sorry, but in this case, Trader is 100% correct.

[Robert Green]

Is that one of those DAMHIKT statements? What did you do to free him?

[Robert Green]

It pains me to do this, but Trader's right about this. The concept of higher air flow resulting in greater heat transfer is the guiding principle behind the calculation of the wind chill index. Any restrictions placed on what wind chill means are irrespective of the science behind its calculation.

The clearest example I can think of heat transfer via moving air is like Trader's car fan example. Faster computer CPU speeds (and power consumption) forced the industry to mount fans atop their CPUs. They did that because passive cooling, even from massive heat sinks, caused the faster CPUs to burn up. Moving air removes heat more quickly than still air, whether it's a CPU, a pipe or a human being. Hair dryers would incinerate themselves without a fan to transfer heat from the heating coils.

Correct, but evaporation does play a small role, as do many other things. Ask yourself whether you'd rather be stranded outside at 0F with a wet jacket or a dry one. (-: (And yes, I know that wet clothes transfer heat more rapidly than dry ones and insulation loses R-value when wet.)

Evaporative cooling is more important to windchill's fraternal twin, the heat index. That's when sweating in a humid environment does not cool the skin well and so 100F degrees in Atlanta or DC can feel like 110F in the desert. It seems that the two concepts got slightly mashed up in this thread. There's fascinating reading at:

that describes a number of controversies associated with calculating wind-chill, windchill, wind chill, wind chill index or the wind chill factor (the fact that no one can agree what to call it speaks volumes about its controversial nature).

[trader4]

I really don't care what you like or don't like. Go back to the beginning of this whole discussion on windchill. I presented facts, science, perfectly civily. When you still have some idiots who insist that windchill is all about evaportation, that it's effects don't extend to inanimate objects, and are still insisting that they are right, well, then it's not my problem. I suppose if they wanted to argue that Ohm's Law is V=IR^2, I should just accept that and not get annoyed after about 20 posts. And even then, what did IO say? "good grief". If you can't handle that, you should grow up.

And for further proof, go look at who started this all up again after it was covered in another thread. One person made a post, clearly trolling and trying to revive it all over again. I didn't take the bait. Neither did a bunch of other posters, but then someone else, who was involved in the previous thread and should have known better, had to chime in and start it up again. So, perhaps you should save your comments for them.

[trader4]

Thanks for the support. And I'd also point out that I'm not impressed by the number of voices. It's not the number, it's if what they are saying follows physics or is just nonsense. If a growing number of people say that V=IR^2, does that make it right? good grief.

[trader4]

Thank you for the support. It's good to see we can agree on something.

[krw]

Well, Ohm's law is E=IR, but you've got the rest. ;-)

[krw]

V=IR

Apparently it makes Global Warming "right".