Numerical and experimental analysys of the laminar burning velocity of hydrocarbons mixtures

This thesis work has the aim to investigate on burning velocities of premixed laminar flames. Laminar burning velocity is a fundamental parameter describing how a flat flame propagates into quiescent unburned mixtures ahead of the flame at a specific pressure and temperature. Various gaseous hydrocarbon mixtures have been examined: methane (with amounts of ethylene, propylene and hydrogen), ethylene, propylene and propane (with amounts of hydrogen). In all the cases atmospheric air has been considered as oxidizing agent. All the premixed flames are at the temperature of 298 K and atmospheric pressure; the laminar burning velocity has been reported as a function of the equivalence ratio. Deriving the compositions of the fuel mixtures from the various equivalence ratios, a numerical method has been used first; the software Cantera, through a chosen kinetic model (LLNL) and a compilation program (Python), has given the trends of the velocities for all the mixtures. After this phase, an experimental campaign has been programmed. Using the heat flux method, all the necessary experimental data have been obtained. The experimental data have been elaborated and compared with other experimental data from literature, numerical data and, for some fuel mixtures, data derived from mixing rules. Through this analysis it has been possible to evaluate the detailed kinetic model used before and the validity of the studied mixing rules.