带有进排气旁通的相继增压柴油机的计算分析

建立了带有进排气旁通的相继增压柴油机稳态仿真程序,缸内过程采用充满与排空法,进排气过程采用一维非定常流动模型,选择有限体积法对其进行离散求解。对某船用带有进排气旁通的相继增压柴油机,进行了多组性能模拟计算,结果表明:计算结果与试验数据基本一致;柴油机转速在855～920 r/min时,开启旁通阀,能增加压气机的空气流量,避免喘振,并提高了增压压力,降低了排温,改善了柴油机的大扭矩性能,但柴油机的经济性有少量降低。

Calculation and Analysis of the Sequentially Turbocharged Diesel Engine with Intake and Exhaust By-pass System

A simulation code was designed for the steady state performance of the sequentially turbo-charged diesel engines with an intake and exhaust connecting system. The cylinder code was based on the "filling and emptying" method. The manifold code was based on the finite volume approach. The code was u-tilized to simulate the performance of the sequentially turbocharged diesel engine with intake and exhaust connecting system. The results show a good agreement between measure and simulated data and that the intake and exhaust connecting system can increase the mass flow rate and outlet pressure of compressor, avoid the surge of compressor, improve the high touque performance of engine, but slightly penalize the economic performance of engine in the range of 850 r/min to 920 r/min of engine speed.