02011nab a2200205 4500 20260520003108.0 260224s2015 xxu ing Inglés Investigation of Cycle-to-Cycle Variability of NO in Homogeneous Combustion ene./feb. 2015 14/09/2015 ; 14/09/2015 12 p. ; 111-123 Transcripción del resumen del autor: Cyclic variability of spark ignition engines is recognized as a scatter in the combustion parameter recordings during actual operation in steady state conditions. Combustion variability may occur due to fluctuations in both early flame kernel development and in turbulent flame propagation with an impact on fuel consumption and emissions. In this study, a detailed chemistry model for the prediction of NO formation in homogeneous engine conditions is presented. The Wiebe parameterization is used for the prediction of heat release; then the calculated thermodynamic data are fed into the chemistry model to predict NO evolution at each degree of crank angle. Experimental data obtained from literature studies were used to validate the mean NO levels calculated. Then the model was applied to predict the impact of cyclic variability on mean NO and the amplitude of its variation. The cyclic variability was simulated by introducing random perturbations, which followed a normal distribution, to the Wiebe function parameters. The results of this approach show that the model proposed better predicts mean NO formation than earlier methods. Also, it shows that to the non linear formation rate of NO with temperature, cycle-to-cycle variation leads to higher mean NO emission levels than what one would predict without taking cyclic variation into account. 1 Oil and Gas Science and Technology 70 ARTICULO Karvountzis-Kontakiotis, A. 54866 Ntziachristos, L. 54867 189200 189200 0 0 0 0 257019 BAAB BAAB 2026-03-06 200061432 0 200061432 2026-03-06 00:19:25 2026-03-06 ARTICULO