Simulation of the Performance of Two-stage Turbocharged Diesel Engine with Different LP/HP Pressure Ratios
With the requirement of higher BMEP for diesel engines, two-stage turbocharging has been used to enable high boost o- ver a wide engine speed range. While matching with two-stage turbochargers, it is the LP/HP pressure ratio that has important effect on engine performance. In this paper the regulated two-stage turbocharging system with different LP/HP pressure ratios were designed for CA6DL2 diesel engine to improve its low-speed torque characteristic. GT-POWER was used to simulate the engine performance and de- termine the optimal openings of the regulated valve. The simulation results show that with two-stage turbocharging, the engine torque can be improved up to 6%compared to formerly used single-stage turbocharger at low speed range. But under high-speed operating condi- tions, the engine pumping loss will increase greatly since the pressure ratio and efficiency of HP compressor are very low. It indicates that using the method of selecting available commercial turbochargers, a relatively small LP/HP pressure ratio between two stages will bring benefit that it can maintain higher turbocharger efficiency when the regulated valve is open.
two-stage turbocharging diesel engine pressure ratio split simulation
Shi Xin Li Fengming Zhang Hong
School of Mechanical Engineering, Beijing Institute of Technology
国内会议
上海
英文
534-541
2017-10-24（万方平台首次上网日期，不代表论文的发表时间）