A fluid can be in the form of a liquid or a gas. Its movement, generally described by the term "flow" is characterized by the flow rate. This is the amount that passes through a given surface. According to the experiments, the flow rate depends as well on the fluid as on the support of its flow, whether it is a pipe or a porous medium. In this work, a porous medium can be cracked or granulated. In the second part of the article, the author presents some forces that can be exerted both on the medium and on the fluid. They are classified into inhibitory and catalyzing. Finally, an example of an energy balance is described in the form of Bernoulli’s law.