improve and optimize the combustion process. Finally, the in-cylinder pressure data are analyzed to obtain the apparent heat release rate. The images of mixture formation and flame development are analyzed together with the heat release and expected to provide very accurate information prior to the combustion process and exhaust emissions.

Figure 3.1: Influence of the mixture formation on evolution of combustion process

3.1 Experiment set up

3.1.1 Rapid Compression Machine

The experimental apparatus can be divided into several systems such as rapid compression machine, single-shot common rail system, data acquisition systems and exhaust emission measurement systems.

The general schematic diagram of experiment apparatus is shown in Fig.2. A free-piston type rapid compression machine (RCM) was used to simulate diesel combustion in a constant volume over a wide range of ambient temperature and pressure conditions similar to actual diesel engines. In addition, systems were