This work presents a dispersion study of a multi-sport stadium using local scale simulation (CFD) using the open-source software code_saturne. A recently developed time scheme for indoor airflow is used. A high-fidelity numerical mesh is built from a cloud of points and used. Besides providing the local dynamics in the stadium, simulations results are compared to experimental PM10 concentration data from a handball game, where firework were lighted, and a 0-D model. CFD results were shown to correctly reproduce the PM10 variation.