In this thesis the VEPZP model (VElocity Propagating ZOnal model) is developed. It subdivides a room in to several zones exchanging air. This allows estimating the influence of location and intensity of heat sources and ventilation devices on airflow pattern and temperature distribution. The VEPZO model is coupled to a Genetic Algorithm. In an exemplary application a new ventilation system for an aircraft cabin is developed. A further use case is the investigation of the energy efficient combination of mechanical and window ventilation in a classroom at different outside air temperatures.