Environmental monitoring using of sensors network seems to be a significant alternative of current detection techniques for a huge and critical problem in the Mediterranean area : wildfires. However, we don’t know the real capacity and reliability of this particular tool under special conditions. Modelling and simulation appear like an essential aspect to understand the behavior of this special network. Discrete Event system Specification (DEVS) formalism is able to describe the asynchronous nature of the events occuring in Wireless Sensor Network (WSN). In this paper we introduce a DEVS sensor model with a particular focus on network management. We decide to describe a node by components-based approach and to provide a simulation tool with a focus on two main characteristics : modularity of components and the environnemental interactions. Our model with a detailled definition of components of WSN node can bring some responses to routing techniques. This first step in simulation and analysis of results confirm utility, capacity and modular aspect of our model to represent a large number of nodes and specific characteristics of WSN in critical environmental conditions.