高压共轨柴油机高海拔全负荷标定

摘要

The plateau calibration is of importance in the development of common-rail diesel engine. The full load calibration experiment of common-rail diesel engine at different altitudes was conducted by high altitude (low air pressure) , and the relationships between the optimal injection parameters and the altitude were investigated. Then, the power experiment at different altitudes was completed. Results show that the optimal fuel delivery per cycle per cylinder decreases with increasing altitude, which decreased by 2%?% when the altitude increased by 1 000 m. The optimal injection advance angle and common-rail pressure increase with increasing altitude within medium and high rotated speed ranges. The maximum torque and rated power decreased by 2.8% and 2.9%, respectively, with the altitude increasing by 1 000 m. The speed coefficient of diesel remains unchanged at different altitudes. The fuel economy remains roughly unchanged at different altitudes within medium and high rotated speed ranges, but it experiences a deterioration at lower rotated speeds, which increased the specific fuel consumption by 3.9% with the altitude increasing by 1 000 m.%高原标定是高压共轨柴油机开发过程中的重要环节.利用高海拔(低气压)标定试验系统进行了高压共轨柴油机不同海拔下的全负荷标定试验,研究了最佳喷油参数随海拔的变化,并进行了高压共轨柴油机不同海拔下的功率试验.研究结果表明,最佳循环喷油量随海拔的增加而减小,海拔每升高1 000m,循环喷油量下降2％～4％；中高转速下最佳喷油提前角和轨压随海拔的增加而增大.海拔每升高1 000m,最大转矩降低2.8％,标定功率下降2.9％.不同海拔下柴油机速度系数保持不变.不同海拔中高转速燃油经济性基本保持不变,低转速下燃油经济性恶化,海拔每升高1 000m,低转速下燃油消耗率增加3.9％