Abstract
The paper aims at graphic presentation of two methods serving for calculation of pressures and temperatures of a piston gasoline combustion engine; i. e. by use of the:
- Thermodynamics method
- Method of comparative cycle calculation by use of Wibe's function of combustion Mathematical models for the two methods were made in the programme Mathcad 7 Professional.
Basing upon the obtained results a comparison of indicated pressures calculated by use of the thermodynamics method and Wibe's method in relation to indicated pressure in a Gasoline Direct Injection Engine (GDI) was made.
Calculations were carried out for a GDI engine during work on ultra lean mixture and calculation results were presented in two - dimensional diagrams.