Experimental comparison between HVO and non-renewable diesel on performance and emissions in a light-duty diesel engine using conventional and alternative combustion strategies

This thesis work comes up from an experience of six months in the dynamic test bench at the Energy Department of Politecnico di Torino. With the supervision of Engr. Manelli, Engr. Mancarella and Prof. D'Ambrosio, I was involved in an experimental activity that gave me the possibility to know and understand the principles and the life in the engine test bed. The main tasks I was in charge to do were supporting the acquisition activity, data analysis and post-processing. In addition, I assist in the maintenance of the testbed and the installation of new devices. The thesis presents the main activities I got involved. The common link between all tests is the study of the potential of HVO (Hydrotreated Vegetable Oil) as a renewable fuel for combustion and emissions in a diesel engine. HVO represents an alternative diesel that can be used as a 'drop-in' fuel. It is made by a refinery-based process that converts vegetable oils and animal fat into paraffinic hydrocarbons. It presents higher quality than standard diesel, with no sulfur and aromatics content and a higher cetane number. There are multiple reports of HVO improving combustion and emissions properties. In this thesis, different investigations are proposed. Firstly, two points at low regime and full load condition were taken into consideration. Then, for completeness, a curve at high loads. Afterwards, pollutants maps were implemented to understand the zones of the engine map where HVO performs better than diesel. In conclusion, the PCCI combustion is implemented in the engine, and with the employ of EGR some trade-offs are performed, showing if there are benefits of HVO also in advanced combustion strategies.