Studying the chemistry of HCCI in rapid compression machines

The rapid compression machine is an ideal tool to investigate the chemistry of the HCCI engine as important factors controlling both devices are the same. There is no tool that describes, meaningfully, the physical and chemical processes occurring in one of the simplest research tools, the rapid compression machine and typically, processes are simulated based on gross oversimplifications. This study highlights some factors that optimise the RCM as a research tool, and the effect of using diluent mixtures on measured ignition delay times. It shows that there is no straightforward method to define characteristic heat loss associated with diluent mixtures.