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1 14 II ( ) 2014. 5. 22 ..1 ..1 ..1 ..1 ..2 ..3 ..4 ..4 ..5 ..5 ..6 heat transfer ( ) heat conduction conductive heat transfer ( ) convective heat transfer ( ) radiative heat transfer ( ) [ ]/([ ][ ]) = [ ]/[ ] SI W m 2 k thermal conductivity J = k T x [ ]/([ ][ ]) C* - 1/6 - 14 II ( )

2 T t = kC* 2T x2 = 2T x2 = k/C* [ ]/[ ] (thermal diffusivity)* k 25 C 1 atm 0 C k /W m-1 K-1 / mm2 s 1 k /W m-1 K-1 / mm2 s 1 22 237 97 176 18-8 16 80 23 398 117 v C* vC* C* mPa v s - Wiedeman-Franz Lorenz

3 K/(s T ) = 10-8 W K-2 6 107 S/m 400 W m-1 K-1 TX TY LA kA A LB kB B* Soret - 2/6 - 14 II ( ) J J = kA T TXLA = kB TY TLB T A B h = k/L J = hA hBhA + hB (TY TX) = h* (TY TX) h heat-transfer coefficient [ ]/([ ][ ]) 1/hA 1/hB 1/h* 5 W m 2 K 1 50 W m 2 K 1 10 0 TY TX b Q Q = b (T TY) C Q Q = C dT/dt dTdt = (T TY)/ = C/b T = TY + (TX TY) exp( t/ )

4 Newton s law of cooling * S Tu Tig C* k x Tb - * Tu Tb Tig x - 3/6 - 14 II ( ) Mallard-Le Chatelier xTTTTCkS1*uigigb = - JH JA JT JR JI = JA + JT + JR 1 IRTEH=++JJJJJ JH/JE JA/JI IAEHJJJJ= JE - JE = sT 4 s = 10-8 W m-2 K-4 - TA TB B J = s(TA4 TB4) 4sTm3 (TA TB) Tm A B (TA + TB)

5 /2 4sTm3 maxT = mm K 500 nm 6000 K 300 C C Tig - 4/6 - 14 II ( ) r TA A TB B dsA dsB A B qAB BA2BA4 AABddcoscosssrTq qqs= B A qBA TA = TB A B QAB qAB B dsB QAB = sAs (TA4 TB4)FAB FAB geometrical factor, angle factor, shape factor.

6 FAB sA = FBA sB 104 W m 2 K 1 104 105 W m 2 K 1 10 TW T 30 dsA dsB qA qB r log (TW T)/K 0 1 2 3 3 4 5 log (h/W m 2 K 1) - 5/6 - 14 II ( ) A B A 420 K B 380 K A B 1 m2 1 s J - s 6 10-8 W m-2 K-4 A B 420 K 380 K A B A B 1 m2 1 s J - 6/6.