Experimental study on combustion characteristics of opposed piston diesel engine with mechanical-hydraulic hybrid power output

A test bench for an opposed piston diesel engine with mechanical-hydraulic hybrid power output is established. Heat release rates of the engine are calculated by its indicator diagrams measured from experiments with mechanical and hydraulic energy output modes, and its combustion characteristics with these two modes of energy output are investigated. Comparison of the combustion characteristics of such engine with those of a traditional opposed-piston engine shows that with hydraulic mode, the increase of load has a greater influence on slow combustion period and after combustion period, and it delays the center of heat release rate as well. Besides, the hybrid engine with hydraulic mode has a faster heat release rate in rapid combustion period and a longer after combustion duration compared with a traditional opposed-piston engine.