A multi process coupled gas exchange model of free piston power system for scavenging control applications

Abstract

Operational instability of linear free piston generator (LFPG) is the main challenge restricting its further development, in which the fluctuation of gas exchange is the key that causes unstable work. It must be controlled to overcome challenges in the scavenging process. The study presents a full-cycle gas exchange model for the need of scavenging control, and the model features with a coupling effect of the LFPG motion, combustion, thermodynamic, and gas flow. Scavenging test also confirms the correctness of the model. The numerical calculation of the model also supports that it is available for the description of gas exchange in the LFPG. The simulation results of the control strategy using the model suggest that it can be used for the control of stable quantity of the in-cylinder fresh charge if combustion fluctuation.