One-dimensional flame propagation and the behavior of the end gas in a constant volume tube-shaped vessel were observed with schlieren and direct photography for n-C_7H_<16>/O_2/Ar mixtures in order to investigate the knock phenomea. The experiments were carried out varying the initial temperature from 430 to 550 K. The strong pressure oscillation occurred at 480K. The occurrence of low temperature flame in the end gas and the deceleration of the propagation flame formed by the spark ignition were observed before the occurrence of pressure oscillation. The intense light emission which was considered to be caused by the auto-ignition or the rapid flame propagation occurred near the flame formed by the ignition. The auto-ignition near the flame formed by ignition or the rapid flame propagation seemed to cause the pressure oscillation. The occurrence of the auto-ignition or the rapid flame propagation followed by pressure oscillation was discussed based on the properties of ignition delay obtained by the numerical simulations.
|Number of pages
|The Proceedings of the International symposium on diagnostics and modeling of combustion in internal combustion engines
|Published - 2012