Simulation on the effect of the combustion parameters on the piston dynamics and engine performance using the Wiebe function in a free piston engine

Numerical simulations were conducted to observe the relationship between the combustion phase and the piston dynamics in a free piston engine. The simulations were conducted with commercial software, MATLAB/SIMULINK®. The Wiebe function was used to simulate the combustion process. The combustion parameters such as combustion duration and the spark timing were varied at various piston initial velocities at compression stroke. The indicated mean effective pressure (IMEP) and the mass fraction burned (MFB) were analyzed as indicators of the engine performance.