In this work, the mechanism instability of heat transfer and fluid flow across an electronic device has been conducted in anunsteady two-dimensional environment.The pore structure has a constant central heat source Th at below and has been cooled with lower temperature Tc from its vertical sides moved upper ward with constant velocity V0, while the other walls were considered to be thermally insulated.The governing equations of a Darcy- Brinkman-Forchheimer have been adopted, they are discretized using the finite difference method for non-uniform grids and numerically solved employing Runge-Kutta fourth-order method.The principal objective of this contribution is the investigation of the impact of moving boundaries on the occurrence of thermal and dynamical instabilities in the porous space using partial heating at the bottom. The calculations have been carried out with porosity approaching 1 and a series of mixed convection parameters bounded by 0.5 and 35. Reynolds and Prandtl numbers, along with Darcy's value, have been fixed respectively to 100, 0.71, and 0.1. The obtained results have shown that at different time stations, interesting disturbances in the stability of flow have been provided in the current work. Thus, five different flow structures were highlighted depending on the Richardson number. The employed model can be useful for describing the physical behaviors of cooling of the electronic components present in almost all devices.