With a recent paradigm shift and substantial research activities in the area of renewable fuels of non-biological origin, the project initiated the investigations in ammonia combustion. The first step in this direction envelopes the presented fundamental research that investigates the possibility to use ammonia-hydrogen blends in a humidified cycle turbine with the aim to maintain high efficiency, comparable to that of conventional dry-low NOx technologies using methane. By using CHEMKIN-PRO reaction networks, novel chemical reaction kinetics, all supported by experimental investigation using steam injection, the research proved that it is possible to obtain stable flames with such approach and that the investigated direction is opening a new opportunity for further investigation of the topic. The research presents an important starting point for ammonia combustion research within the project since it is possible to fully experimentally evaluate ammonia combustion also on existent infrastructure.
COBISS.SI-ID: 16625691
Work investigates the impact of a paraffinic fuel on combustion and emissions of a compression ignition engine by examining alternative injection strategies for the full exploitation of the fuel characteristics. The paraffinic fuel used was the HVO (Hydrotreated Vegetable Oil) produced by Neste Oil with the brand name NEXBTL. The key contribution of the study is a comprehensive analysis of the phenomena influencing combustion parameters, as well as interlinking the effects of different variations of injection pressure (default and 300 bar higher), pilot injection timing and main injection timing on gaseous emissions and particulate matter (PM). The findings have shown that HVO results in up to 40% reduction of engine-out PM and HC emissions without appreciable changes in NOx emissions. The significant reduction of engine-out PM levels, facilitates the adoption of measures for NOx emissions limitation. In terms of project relevance, the analysed results suggest, that paraffinic fuels might be suitable candidates for improved performance in highly dilluted combustion process that incorporates large amounts of EGR in composition of primary air.
COBISS.SI-ID: 17002267
The paper focuses on the implementation of a comprehensive and robust optimization procedure for use of synthesis gas fired in spark ignited engine. Innovatively designed workflow is for the first time incorporating also a thorough operational stability analysis for evaluation of the engine operation durability while using off-design fuels. The results, derived from experimental data discuss the lean operation conditions as a measure to reduce environmental footprint of energy generation when using low H2 content synthesis gas. The findings propose novel control strategies to achieve a very low (16.5%) power de-rating factor, while still relying on stoichiometric mixture and simultaneously meeting the TA-Luft and EPA emission limits. The ignition properties of the mixture suggest, that low H2 syngas features lower rate of heat release, hence making highly diluted conditions in combustion chamber challenging for achieving acceptable emissions. In relation to the project, the paper provides valuable data on acceptable H2 content in the fuels when implementing high EGR rates.
COBISS.SI-ID: 16879643