Martin Nijs

Low Temperature Gasoline Combustion – Potential, Challenges, Process Modeling and Control

Worldwide efforts in combustion development focus on reducing carbon dioxide emissions. Besides improving conventional combustion systems, also alternative systems have to be considered as a measure to achieve that goal. The present work aims to increase the usability of gasoline controlled auto-ignition (GCAI) with its potential benefit regarding fuel consumption of up to 30 %.

Air path models for gasoline engines with extended valve train variability

Two novel engine control models which account for multiple parameters influencing the air path in gasoline engines with extended valve train variabilities have been investigated at the Institute for Combustion Engines at RWTH Aachen University within the scope of FVV (Research Association for Combustion Engines) project 938 “Air path model for variable valve trains”. The first model constitutes static as well as learnable physical-neuronal functionalities that are integrated into the engine management software of the FVV engine control unit. The second model concerns a real-time gas exchange algorithm in which high-resolution pressure signals on the intake and exhaust port as well as the cylinder pressure signals were used. Hereby, the respective software was implemented on a high-performance rapid control prototyping unit.

All lambda 1 gasoline powertrains

The introduction of new emission legislations in Europe (EU6d-TEMP) and China (CN6b) increases the pressure on the automotive industry to develop new and better exhaust gas aftertreatment and combustion systems. The fulfilment of PN and NOx targets in real world driving scenarios and increasingly electrified powertrains have led to the introduction of gasoline particulate filters (GPFs) and enlarged catalytic converters. Now, on top of these major upgrades, the monitoring of CO emissions according to Real Driving Emissions (RDE) legislation puts a potential ban on high load enrichment for thermal component protection into focus. Hence, new technologies which enable Lambda 1 operation in the entire map of a gasoline engine are urgently required. This paper presents technology packages for component protection at high load stoichiometric operation as well as operational strategies for ultra-low CO emissions in all real driving scenarios. Assessed solutions span from base engine modifications to water injection and vehicle cooling concepts as well as to control functions. Favorable combinations are identified taking into consideration costs and realistic integration in ongoing vehicle programs.

Biofuels for Combustion Engines

The requirements on the development of combustion engines have dramatically changed in the past decade. This includes strict emission laws, CO2 emission reduction, different propulsion concepts including powertrain electrification and a reduced time to market with an increased number of engine variants. One alternative to mitigate both the need for fossil burnings and the CO2 emission reduction is the use of alternative fuels from biomass. Thus, different legislation authorities aim for higher proportions of alternative fuels on the market. However, this strategy involves changes on different development domains for combustion engines. This paper presents ongoing research taking place within the interdisciplinary activities at the Institute for Combustion Engines. The effects on the control system as one enabler of further investigations are presented from the perspective of variant management and complexity handling. Proceedings of the research on innovative control algorithms for fuel adaption are outlined. At third, we discuss the impact of direct injection of alternative fuels on liner wetting and piston ring development. At last, the combustion of fuels from biomass with regards to the emissions formation is investigated from two points of view: for gasoline combustion methods, the characteristics of gaseous emission are presented. For Diesel combustion, we show the different formation of particles by applying diverse measurement methods.

Steuergerätefähige Luftpfadmodelle Für Ottomotoren Mit Erweiterter Ventiltriebsvariabilität

Zur Durchfuhrung von Forschungsaufgaben an Motoren mit erweiterter Ventiltriebsvariabilitat wurden im Rahmen des FVV-Vorhabens 938 „Luftpfadmodell fur variable Ventiltriebe“ am Lehrstuhl fur Verbrennungskraftmaschinen (VKA) an der RWTH Aachen University neuartige Motorsteuerungsfunktionalitaten untersucht, die insbesondere die Mehrdimensionalitat des Luftpfads berucksichtigen. Neben einem lernfahigen, physikalisch-neuronalen Fullungsmodell, welches in die Motorsteuerungssoftware des FVV-Steuerrechners integriert wurde, konnte eine echtzeitfahige Ladungswechselrechnung realisiert werden. Die Umsetzung der Ladungswechselrechnung mit hochaufgelosten Drucksignalen auf der Ein- und Auslassseite sowie dem Zylinderdruck wurde auf einem leistungsfahigen Rapid-Control-Prototyping-Steuergerat durchfuhrt.