**3. Calculation of periods of phases of fuel injection in the spark – Ignition engine with direct fuel injection during work on the heterogeneous mixture**

Carried out calculations aim at determination of durations of particular phases of injected fuel stream in the Mitsubishi GDI engine during work on the stratified mixture, including resistances prevalent inside the cylinder [8]. The mathematical model was elaborated by use of *Mathcad Professional.*

**3.1. Calculation of period t1**

α0 – the moment of the beginning injection of the fuel stream

**Figure 7.** First sector i.e. contact of fuel mixture with the bowl of the piston

ing air resistance (*Fig.7)*.

Time t1, from the fuel injection moment to contact of the stream with the piston head, includ‐

Stratified Charge Combustion in a Spark-Ignition Engine With Direct Injection System

http://dx.doi.org/10.5772/53971

93

The phases of injected fuel stream during work on the stratified charge are shown in *Fig.6*.

**Figure 6.** The phases of injected fuel stream

For the calculation model, the total time needed to cross a distance from injection moment to the sparking plug points reaching was divided into four stages, namely:

