The free-piston gasoline engine linear generator (FPGLG) is a new kind of power plant\nconsisting of free-piston gasoline engines and a linear generator. Due to the elimination of the\ncrankshaft mechanism, the piston motion process and the combustion heat release process affect each\nother significantly. In this paper, the combustion characteristics during the stable generating process\nof a FPGLG were presented using a numerical iteration method, which coupled a zero-dimensional\npiston dynamic model and a three-dimensional scavenging model with the combustion process\nsimulation. The results indicated that, compared to the conventional engine (CE), the heat release\nprocess of the FPGLG lasted longer with a lower peak heat release rate. The indicated thermal\nefficiency of the engine was lower because less heat was released around the piston top dead centre\n(TDC). Very minimal difference was observed on the ignition delay duration between the FPGLG\nand the CE, while the post-combustion period of the FPGLG was significantly longer than that of the\nCE. Meanwhile, the FPGLG was found to operate more moderately due to lower peak in-cylinder\ngas pressure and a lower pressure rising rate. The potential advantage of the FPGLG in lower NOx\nemission was also proven with the simulation results presented in this paper.
Loading....