A phenomenological explanation of the autoignition propagation under HCCI conditions

Abstract

A phenomenological explanation about the autoignition propagation under HCCI conditions is developed in this paper. To do so, diffusive effects from the burned zones to the fresh mixture, pressure waves based effects and expansion effects caused by combustion are taken into account. Additionally, different Damköhler numbers have been defined and evaluated in order to characterize the phenomenon and quantify the relevance of each effect.

Sensitivity analysis and validation of a predictive procedure for high and low-temperature ignition delays under engine conditions for n -dodecane using a Rapid Compression-Expansion Machine

“…If a homogeneous gas bulk is generated in the combustion chamber, the in-cylinder conditions referred to such gas core can be replicated in the 0-D model before the ignition, leading to a proper evaluation of the chemical kinetics referred to the ignition delay. Finally, the existence of such homogeneous gas bluk has been demonstrated in [33].…”

Experimental validation and analysis of seven different chemical kinetic mechanisms for n-dodecane using a Rapid Compression-Expansion Machine

“…Three thermocouples measure the walls temperature in the liner, in the piston and in the bowl, respectively. Fully controlled initial and boundary conditions are guaranteed thanks to the turbulence generated during the filling, which ensures a homogeneous environment in the combustion chamber, as demonstrated by some previous CFD calculations [37].…”

Simulation of predictive kinetic combustion of single cylinder HCCI engine

“…A simulation model can provide insight into the effect of different parameters by isolating some of their values [16]. Various simulation models have been proposed [17][18][19][20]. In general, the models can be grouped into two categories; chemistry model and fluid dynamic model [20].…”