Simulation des phases de fonctionnement transitoires d'un moteur diesel semi-rapide à suralimentation séquentielle

The Selendia simulation software dedicated for diesel engines is presented. Based on the filling and emptying method, it calculates the evolution of the engine and turbocharger rotation speed and the temperature and the pressure in different control volumes (manifolds, cylinders) during the dynamic operations of the engine. Its application to a sequentially turbocharged engine leads to the optimisation of the turbocharging system characteristics such as the time lag between the opening of the air and gas valves. Its predictive capacities permit to test by simulation the performances of a new engine and then to guide the engine designers.