Sökning: "Spark Ignition"
Visar resultat 6 - 10 av 77 avhandlingar innehållade orden Spark Ignition.
6. On the Impact of Piston Motion and In-Cylinder Charge Composition on Energy Release, Auto Ignition and Emission Formation in Premixed Charge Internal Combustion Engines
Sammanfattning : The results presented in this thesis can be divided into four areas of investigation: Investigation of the effect of new volume-crank angle relations on engine emissions, power and efficiency; investigation of nitrogen oxides effect on auto ignition and knock in SI engines; investigation of premixed SI and HCCI engine operation with the alternative fuels hydrogen and reformed methanol gas (RMG); software development of a detailed chemical kinetics zonal engine model. Model development of the in-house two-zone chemical kinetic code focused on expansion of the Jacobian matrix to allow simulations of variable in-cylinder charge. LÄS MER
7. Injection and Combustion of Alternative Fuels in Spark Ignited Direct Injection Engines
Sammanfattning : Increasingly stringent vehicle emission legislation necessitates increasingly efficient combustion engines. The use of direct injection in spark ignited engines improves engine efficiency and reduces CO2 emissions. LÄS MER
8. Improving the Efficiency of Gas Engines using Pre-chamber Ignition
Sammanfattning : The aim of this project is to explore and understand the combustion phenomenon in engines operating on gaseous fuels, and develop technologies as an alternative to the present diesel engine technologies for heavy duty applications; which are facing severe challenges like stringent emissions norms, high technology costs and unsustainable fuel supply. The studies presented in this thesis focus on the application of pre-chamber ignition system in heavy duty natural gas engines, as a means to improve fuel efficiency and reduce NOx emissions. LÄS MER
9. Modeling of Flame Propagation in Spark Ignition Engines
Sammanfattning : Developers and manufacturers of gasoline engines are struggling to improve fuel economy and minimize negative environmental effects. Hence, lean burn and direct injection (DI), in particular stratified charge (SC), spark ignition (SI) engines are of special interest. LÄS MER
10. Air charge estimation in turbocharged spark ignition engines
Sammanfattning : Turbocharged (TC) spark-ignited (SI) engines are popular as they combine high power output with good fuel economy. Furthermore, their emissions can be successfully reduced using a three way catalyst (TWC) provided that the air-fuel ratio is precisely controlled. LÄS MER