中冷器压降对船用相继增压柴油机性能的影响研究

Study on the Influence of Intercooler Pressure Drop on the Performance of Marine Successively Supercharged Diesel Engines

相继增压技术的运用能够兼顾中高速船用柴油机在低速和高速下的性能指标要求,弥补了发动机转速跨度较大时普通增压技术的不足。在该技术实施过程中,发动机进气系统的其他部件仍然可能对发动机的各项性能指标产生影响。本文在一台16V船用相继增压柴油机上,通过耐久试验,研究了中冷器压降对发动机性能的影响。结果表明:随着中冷器压降的增大,进气流量减小,导致发动机的燃油消耗率、烟度和涡轮前排气温度也随之上升。同时,增压器压气机的运行逐渐接近喘振区,从而显著增加了增压器发生喘振的风险,对发动机的经济性、排放性、动力性和可靠性产生了极大的影响。因此,在发动机运行过程中,需要对中冷器前后的压降进行监控,并定期对中冷器进行维护保养,必要时还需进行更换。

The application of sequential turbocharging technology can balance the performance indicators of medium-and high-speed marine diesel engines at low and high speeds,making up for the deficiencies of ordinary turbocharging technology when the engine speed span is large.However,during the implementation of this technology,other components of the engine intake system may still have an impact on various performance indicators of the engine.This article studies the impact of intercooler pressure drop on engine performance through endurance testing on a 16V marine sequential turbocharged diesel engine.The results show that as the pressure drop of the intercooler increases,the intake air flow decreases,resulting in an increase in the fuel consumption rate,smoke density,and exhaust temperature before the turbine of the engine.At the same time,the operation of the turbocharger compressor is gradually approaching the surge region,which significantly increases the risk of surge in the turbocharger and has a great impact on the economy,emissions,power and reliability of the engine.Therefore,during the operation of the engine,it is necessary to monitor the pressure drop before and after the intercooler,and regularly maintain and repair the intercooler.If necessary,it needs to be replaced.