>From: Rick Glazier <[log in to unmask]> >Reply-To: PCBUILD - Personal Computer Hardware discussion List ><[log in to unmask]> >To: [log in to unmask] >Subject: Re: [PCBUILD] running with the cover off >Date: Thu, 7 Sep 2000 10:31:35 -0400 > >Just another opinion... How about wind chill factor? >Isn't that when things are cooler than they might normally >be because of the movement of air? >Isn't the critical question here the AMOUNT of air moving? >Heat goes into the air... That is a law of Physics. >Get rid of the air with an open case, or good air flow through >a closed case, and you get rid of the heat... Period... > I live in the land of "wind chill factors" so I know that you do have a point about the amount of air flow being a factor in cooling but "wind chill" has nothing to do with it. The wind chill factor is due to a person FEELING more cold because the movement of the air increases evaporation from the skin surface. This is also the reason why an increase in humidity makes a person feel warmer - evaporation from the skin surface is reduced. It's a similar phenomenom with machines in that cooling takes place by transfer of heat from the surface of the machine to the surrounding air or other media. If air flow is restricted and the air heats up to the same temperature as the surface of the machine, then no transfer takes place so there is no more cooling. If a constant supply of cool air is available, then the heat from the machine will flow to the cooler air in an attempt to make it warmer. However, the machine will never get colder than it would be normally. It will only cool off faster because the heat transfer away from the machine is more efficient. _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Share information about yourself, create your own public profile at http://profiles.msn.com. Do you want to signoff PCBUILD or just change to Digest mode - visit our web site: http://nospin.com/pc/pcbuild.html