À¯Ã¼¿ªÇÐÀ» ´Ù½Ã óÀ½ºÎÅÍ º¸´Â Áß¿¡ ¿¹Àü¿¡´Â ±×³É ³Ñ¾î°¡°Å³ª ±Ã±ÝÇÏÁö ¾Ê¾Ò´ø ºÎºÐ¿¡ ±Ã±ÝÁõÀÌ »ý°å½À´Ï´Ù.
1. Momentum transport
By random diffusion of molecules there is an exchange of molecules in the z-direction, an 'equal number' moving in each direction (+z and -z directions) between the faster-moving layer of molecules and the slower adjacent layer. Hence, the x-directed momentum has been transferred in the z direction from the faster- to the slower-moving layer.
(¼öÆò ÆÄÀÌÇÁ¿¡¼ ÆÄÀÌÇÁ ¹æÇâ : x ¹æÇâ, ±×°Í°ú ¼öÁ÷ ¹æÇâ : z ¹æÇâ)
ÀÌ·¸°Ô ¼³¸íÀÌ µÇ¾î ÀÖ½À´Ï´Ù.
moleculeÀº moves randomly in all directions and there are fluxes in all directions. À̱⠶§¹®¿¡ net flux°¡ »ý±â´Â °Ç ÀÌÇظ¦ Çß½À´Ï´Ù. ±×·±µ¥ equal number¶ó°í ¾ð±ÞµÈ °ÍÀ» º¸¸é ¿Ö ¹«Á¶°Ç net flux°¡ high to low ¹æÇâÀÎÁö ¸ð¸£°Ú½À´Ï´Ù.
faster moving layer¿¡¼ some molecules°¡ slower moving layer·Î °¡¸é slower moving molecules¿Í ºÎµúÈ÷°í ½ºÇǵ带 ¿Ã·ÁÁشٰí ÇÏ°í, ±× ¹Ý´ë¹æÇâÀ¸·Îµµ ºñ½ÁÇÑ? °°Àº? ¿ø¸®·Î ¼³¸íÀÌ µÅ ÀÖ½À´Ï´Ù. ±×·±µ¥ net flux´Â high velocity¿¡¼ low velocity ÂÊÀ¸·Î »ý±ä´Ù°í ÇÕ´Ï´Ù.
faster ¡ê slower »çÀÌ¿¡¼ equal number·Î ¿Ô´Ù°¬´Ù? Çϴµ¥ net flux´Â ¿Ö faster to slower ¹æÇâÀÎÁö°¡ Á¦ ±Ã±ÝÁõÀÔ´Ï´Ù.
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