RT info:eu-repo/semantics/doctoralThesis T1 Miller cycle and exhaust gas recirculation for a naturally aspirated lean-burn gas engine A1 Neher, Denis A2 Universidad de Valladolid. Escuela de Ingenierías Industriales K1 Morotes de combustion interna K1 Gas natural AB Motivated by tightening emission standards for small natural gas driven cogeneration gas engines, this thesis explores an alternative working process that extends the pre-vailing lean-burn operation with Miller cycle and cooled exhaust gas recirculation (EGR). The combination of these well-established means is expected to improve the trade-off between engine efficiency, NOx emissions and indicated mean effective pres-sure (IMEP) of a naturally aspirated gas engine.Comprehensive series of measurements were carried out in engine operation with Mil-ler valve timing and varying EGR rate. The main focus was put on the potential that the working process offers in improving the trade-off between engine efficiency and NOx emissions at constant IMEP of the baseline engine’s reference operating point. YR 2017 FD 2017 LK http://uvadoc.uva.es/handle/10324/28629 UL http://uvadoc.uva.es/handle/10324/28629 LA eng NO Departamento de Ingeniería Energética y Fluidomecánica DS UVaDOC RD 17-jul-2024