Abstract
The ignition delays of pure n-alkanes and two-component mixtures of n-alkanes were measured by injection into a constant volume chamber at pressures and temperature similar to the compression end of an actual compression ignition (CI) engine. The ignition delays of pure n-alkanes provide a basis for comparison with mixtures in varying ratios of n-pentane and n-tridecane. The low boiling point of n-pentane results in flash-boiling and rapid charge mixing, while the high cetane number of n-tridecane aids ignition. Based on the experimental results an empirical equation has been proposed to calculate the ignition delays at the non-flash boiling zone. Therefore the proposed equation is applied in the flash-boiling zone to confirm the effect of flash boiling on ignition delay. It was found that for mixtures of n-pentane and n-tridecane, the ignition delay depends primarily on the mixture carbon number and ambient temperature at constant temperature, apparently affected by the flash-boiling phenomena.