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In recent years, engine calibration became a very hard task because of the increasing complexity of systems and the severity of the depollution norms regarding Real Driving Emissions (RDE). In particular, optimal engine control during dynamic phases became crucial for reducing pollutant emissions. Beyond the classical engine calibration method based on steady state experiments, methods that integrate the dynamical response of the engine constitute therefore a promising approach. This work proposes a global approach of engine dynamical model-based calibration (DMBC) and optimization based on a dynamic Design of Experiments (DDoE). After a general description of the architecture of the calibration process, the paper focuses on the methodology for the design of DDoE.

In order to reduce greenhouse gases and respect stringent pollutant emission regulations, the modern engine is increasingly required to incorporate energy recovery systems to enhance performance and increase efficiency. This paper deals with the exhaust energy recovery through turbocompounding. Both series and parallel turbocompounds are discussed. In the first part of the document, literature on turbocompounding is introduced. Then a simulation study carried on AMESim software, using a 2L Diesel engine model is presented. The parallel turbocompounding is simulated by expanding a part of the exhaust gases in a converging nozzle instead of the turbocharger turbine. The power produced is evaluated as a function of the pressure drop in case a turbine is mounted instead of the nozzle. A global study over the entire engine map is described, and two steady state points 2000 rpm, 8 bar and 3500 rpm, 7 bar are chosen.

Unsteady intake wave dynamics have a first order influence on an engine's performance and fuel economy. There is an abundant literature particularly for naturally aspirated SI engines on the subject of intake manifolds and primary runner lengths aimed to achieve a tuned intake air line. A more demanding design for today's engines is to increase efficiency to meet the requirements of lower fuel consumption and CO2 emissions. Today's tendencies are downsizing the engine to meet these demands. And for drivability purposes, the engine is combined with a turbocharger coupled with a charge air cooler. However, when the engine's displacement is reduced, it will be very dependent on its boosting system. A particularly interesting point to address corresponds to the engine's operation in the low speed range and during transients where the engine has large pumping losses and poor boost pressure. This operation point can be optimized using acoustic supercharging techniques.

Emission regulations have become increasingly stringent in recent years. Current regulations need the development of a new worldwide driving cycle which gives greater weight to the pollutants emitted during transient phases or cold starts. Powertrains contain a large number of components such as multistage turbocharger systems; exhaust gas recirculation, after-treatment devices and sometimes an electric motor. In this context, 0D predictive models of heat transfer in the exhaust line, calibrated with experimental data, are particularly interesting. Many investigations are related to the development of precise control laws in order to optimize the light-off of after-treatment elements during the engine starting phase. A better understanding of the thermal phenomena occurring in the exhaust line is necessary. To study the heat transfer in the exhaust line of a Diesel engine during transient conditions, the temperature in the exhaust line must be known precisely.

Transport sector decarbonization is a key requirement to achieve Green House Gases emissions reduction. Future regulations and the large deployment of Low Emission Zones (LEZ) will lead to deep changes in this sector. The green hydrogen appears as a promising fuel, containing no carbon. H2 Internal combustion engine (H2 ICE) offers the opportunities of quick refueling, known reliability, relative low total cost of ownership. It is based on mature manufacturing processes and tools. Hence this solution can be commercialized in a near future, offering a short term pathway to decarbonization and a H2 market growth accelerator. However, hydrogen combustion in air generates NOx emissions, which should be reduced close to zero to fulfill future requirements. The HyMot project gathers seven public and industrial partners to develop an H2 engine for Light Commercial Vehicle (LCV) application offering the same performances as the replaced Diesel Engine.