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Show R E A D method. flU-Eflu/tf <2) where D,. is the direct exchange area from / to j and is expressed in equation (3). Uk^l-a^Rd^ (iforg) *-" 1 €,S, (1 - a, )/W,_y (i for w, 5 and m ) The last term in right side of equation (1) is expressed in equation (4). Q^' =sJSJ{\-aJ)crT; (4) Radiative heat from / to j can be calculated using with the READ and the self absorption ratio. These quantities are calculated using the R H R (radiative heat ray) methodCM. The computational domain is divided into radiative elements, and every element is given an address number in k (k = 1 ~ K). Each element emits TV radiative heat rays. In this study, TV =5000. Whole absorption process of the radiative intensity of each radiative heat ray is investigated. Emitting position and direction of the' n 'th radiative heat ray emitted from the element k are determined using the pseudo random numbers. T w o pseudo random numbers are needed for the decision of the emitting position in two-dimensional problem. For the direction, the two numbers are needed for the decision of the polar angle and the zenith angle. The intensity of the ray decreases gradually during the ray travels in the gas media and when it meets the surfaces. Finally, the intensity of the ray becomes zero. The intensity of the absorption of the ' n 'th radiative heat ray starting at the element k and absorbed in the element /, A/J_^ is defined as the difference between the inlet intensity into the element / , I"n k_>t and the outlet intensity out of the element /, 1 outJc-*l • ^k-*l = hn,k->l ™ loutjc-tl (5) In the case that the element / is a gas element, the outlet intensity of the ray is determined in the Beer's law expressed using the following equation. |