Study of the transient behavior of fluid flow, heat transfer and thermal energy storing or released in/from spongy-porous media to predict the thermal performance and characteristics of the porous media as packed bed system is presented in this work. This system is cylindrical channel filled with porous media (Carbon foam)/ (Silicon rubber). The system consists of working fluid (Water) and spongy-porous medium; they act as the heat exchanger (heating or cooling modes) where thermal interaction occurs between the working fluid and the porous medium. Two different porous media are considered in this study: Carbon foam, and Silicon rubber. The flow of the working fluid (Water) is one dimensional in the axial direction from the top to downward and steady state conditions. The problem is governed by two partial differential equations for the working fluid (Water) and the spongy-porous medium. In this picture, the system can mathematically be modeled using the appropriate conservation equations applied to the working fluid (Water) and spongy-porous medium separately. ukryj opis