Research On Improving Performance Of Marine Main Engine Power System By Combined Waste Heat Recovery

Vessels need to consume huge amount of energy for sailing,and fuel consumption accounts for a large proportion of the vessel operating costs,as a result,the first step to reduce the operating cost is to develop a new technology to reduce fuel consumption.At present,the fuel utilization of the most advanced marine two-stroke intelligent low-speed diesel is close to 50%,but about 25%of the heat energy are still discharged with the exhaust,which are not effectively used.If the waste heat of the exhaust can be reused,then the effect of energy saving and emission reduction can be achieved at the same time.In this paper,we take 10S90ME-C diesel engine as the research object,10S90ME-C is a marine low-speed diesel engine developed by CSSC-MES Diesel Co.,Ltd.based on the patent of MDT,the maximum continuous power of 10S90ME-C is 51000KW,with large amount of waste heat can be utilized.The main works include:First,based on the 10S90ME-C shop test report,a diesel engine working process simulation model was established by GT-POWER as the platform,and verification.The results showed that,the simulation results and the experimental data were consistent,which verified the accuracy of the simulation model.According to the calculation of thermal balance of the diesel engine and evaluation of waste heat,comparative and analysis the necessity to improve the engine exhaust gas temperature by modulating the host in order to improve the entire waste heat which can be recovered of power systemFinally,based on the simulation model,modulate and calculate the host by adjusting the engine timing and bypass the waste gas,analysis the influence of different main engine modulation measures on main engine performance under different working conditions.,and the engine was optimized.Further,establish a simplified mathematical model of Waste Heat Recovery Combined System,and calculate the efficiency of waste heat recovery and emission reduction according to the simplified boundary conditions.The results show that the efficiency of waste heat recovery is obvious,and the energy efficiency design index EEDI(Energy Efficiency Design Index)decreases significantly.