CONTRIBUTION A LA MODELISATION UNIDIMENSIONNELLE DES SOUPAPES DE MOTEURS A COMBUSTIONINTERNE. ETUDES EXPERIMENTALE ET NUMERIQUE

摘要

Modelling internal combustion engine requires a good comprehension of emptying and filling ofcylinders with air or gas mixture. Thus, a bibliographical study of the different phenomena interfering onthese parameters and of the corresponding models is made. A review of the different experimental deviceseen in the literature is also done.Tests in stationary conditions using a manufactured cylinder head are then conducted. The analysis ofthese results is made using the three main valve models: Barré de St-Venant, Benson and Blair. The study ofthe assumptions of these models having showed their equivalence in the case of a flow exiting a pipe, theimpact of different assumptions on the experimental results is analysed in detail. The three models assuminga stationary flow through the valve, some dynamic tests are then performed. These experimental data arethen compared to simulation results from the models. Differences between the three models in the case offlow entering the cylinders appear and are analysed.Last but not least, the assumption of non thermal flow through the valve is investigated. High temperaturetests are performed. Tests conditions did not allowed highlighting the importance of thermal losses, a newmodel taking in account the thermal transfers is proposed. Its theoretical study allows evaluating the impactof these transfers on emptying and filling of the cylinders.