Experimental energy and exergy analysis of turbocharged marine low-speed engine with high pressure exhaust gas recirculation

•Experiment shows adverse effects of cylinder bypass on exhaust gas recirculation.•Exergy analysis shows reducing irreversibility is more help for fuel reduction.•Main irreversibility is in-cylinder burn and EGR has two opposite influence.•Improving temperature gradient and burn uniformity reduce irreversibility.•EGR reduces turbocharger irreversibility but raises intercoolers’.