One of the main objectives of HugYourEngine is to shine a spotlight on individuals who are helping make internal combustion engines cleaner and more efficient. This spotlight is on Stefania Esposito.
Stefania earned her Bachelor’s and Master’s degrees in mechanical engineering at the University of Cassino and the University of Bologna, respectively. She wrote her Master’s thesis at FEV Europe GmbH in Aachen and worked there for almost one year as a project engineer before starting her PhD at the Institute for Combustion Engines (VKA), RWTH Aachen University. Since her Master’s thesis, Stefania has been working on the thermodynamic and fluid-dynamic simulation of spark-ignition engines.
Kelly Senecal (KS): When and why did you get started in combustion research?
Stefania Esposito (SE): I’ve always been interested in the “warm” field of mechanical engineering, but I developed a particular interest in combustion engines in Bologna, during the last year of my Master’s degree. Thanks to great professors and practical experiences at the test-bench, I decided to write a thesis on combustion engines…and I haven’t left the field since! During these last four and a half years, I’ve always found new challenges that keep me passionate about combustion.
KS: Describe your university/research group/lab facilities.
SE: RWTH Aachen University is a public technical university of about 45,000 students, over 20 percent of them international students. The RWTH is one of eleven recognized German universities of excellence and has various funded interdisciplinary research clusters and graduate programs. At the RWTH’s Institute for Combustion Engines (VKA) and Center for Mobile Propulsion (CMP), we conduct research on all topics concerning highly efficient powertrains under the direction of Prof. Stefan Pischinger. Our research focuses equally on combustion engines—we do fundamental research on more efficient combustion processes, alternative fuels and the improvement of engine mechanics, for example—and after-treatment systems, as well as hybrid powertrains, batteries, electric machines, mechatronic systems and fuel cells. The VKA runs 33 engine test benches and a number of special test benches for flow analyses, fuel cells and engine components, including special acoustical measuring and evaluation systems, a highly dynamic (transient) test bench and an air-conditioned emission chassis dynamometer. The CMP allows real-time communication between the different component test benches (via network) in order to help develop intelligent methods for test procedures and engine calibration as well as virtual development (x-in-the-loop). Further, laboratory and technical areas like a chemistry laboratory, measuring technology laboratory, electronic laboratory, mechanical workshop and test-bench workshop are available. The VKA employs more than 300 scientific, technical and administrative employees as well as student assistants.
KS: What are you working on now?
SE: My research is on the development of predictive gas emission models for spark-ignition engines. These models can support the development and optimization of future low-emission, highly efficient electrified powertrains. For my PhD, I’m concentrating on the fundamental investigation and modeling of gas-emission formation mechanisms, with a special focus on HC emissions because of their complexity. I’ve conducted detailed emission measurements on our single-cylinder engine as well as 3D-CFD simulations and emission modeling in a 1D-simulation environment.
KS: What’s your favorite type of flame?
SE: Turbulent premixed!
KS: What’s your favorite fuel?
SE: I admit that I still have a personal preference for gasoline, but I’m open-minded and looking forward to future fuels, I hope fossil-carbon-free. In the end, I like everything that can burn with a turbulent flame!
KS: What advice would you give students thinking about going into combustion research?
SE: I always advise students interested in combustion to follow their interests and not to worry excessively about their future, since we’ll still need combustion for a long time, if not forever! Indeed, I think that during a time of crisis or change like the one we’re now experiencing in energy-related fields, we’re ever more in need of competent people to deal with challenges, especially in research.
KS: Is the IC Engine dead?
SE: Not at all! It’s such a complex, reliable and handy energy conversion system, one that can even be used to burn hydrogen and carbon-neutral fuels. Why should we kill it? In my opinion, with the breakneck pace research is achieving, efficient engines in electrified or hybrid powertrains will allow us to lower CO2 emissions from the transportation sector faster than a hard switch to BEV would.
KS: How is your work helping improve fuel efficiency or reduce emissions?
SE: By focusing on the gas-emission formation mechanisms and simulation, my research can help predict and then improve emissions from future powertrains— not only from the engine itself, but also from the entire powertrain operational strategy.
KS: How would you like to apply your combustion knowledge after you graduate?
SE: I’d like to continue my research in the combustion field: on emissions from alternative fuels, for instance, and on further improving the efficiency of combustion engines.