This paper presents a computational model used for quantitative analysis of heat conduction process in a flat bed of steel round bars. For this purpose, an approach based on using the analogical mathematical description of the electricity and heat flow phenomena was applied. Furthermore, this model is semi-empirical since it uses dependencies determined based on experimental research. The basis for deriving the mathematical dependencies is the geometric model of the system studied, defined by the so-called elementary cell. Each of the mechanisms of heat conduction that occurs within the cell was assigned an appropriate thermal resistance. The total thermal resistance of a cell is a combination of parallel and serial connections of individual resistances. The calculations were made for the temperature range of 0-800 • C, for four bar diameters and two porosities.