OCR Text |
Show /2. where, 0 c= A Nul2R : convective heat transfer rate A : thermal conductivity of gas Nu : Nusselt number Then, each heat balance of gas or particle is obtained by gas (25) particle (26) The other heat balance of wall is also obtained by Eq.(16). Furthermore, the value of Rd{l,J) can be calculated by the Monte Carlo method and the radiation heat absorbed by an element J is obtained by Eq.(19). In the case of Fig. 3 with temperature difference between gas and particle, the numerical results are calculated and shown in Fig. 5. If a heat generation Qh is introduced in gas phase and particle, the temperature difference between gas and particle may be changed and its difference will be important to solve the actual heat transfer problems. s. Radiative characteristics in non-gray mixture of gas and particle In this case of non-gray mixtuie, the gas is non-gray but the particle surface is supposed to be gray. Then, the radiative energy from gas phase in the volume du is dQg=4J Q(V)(dU- : 1tR3Npdu )Eb(V)dV gas (27) where, v : wave number of radiation Eb : monochromatic emissive power of black body Then, the total emissive power of black body is obtained by the integration from 0 to 00. |