GDI喷油器温升对其性能的影响研究

Influence of Bulk Temperature Rising on the Performance of GDI Injector

为了研究GDI喷油器本体温升规律,建立了电、磁、热子系统模型,根据各子系统之间耦合关系,利用数值模拟与试验相结合的方法研究了GDI喷油器本体温升规律及对其综合性能的影响。研究结果表明:GDI喷油器在通电后具有较快的温升速率,且温升受驱动电流、驱动脉宽和燃油压力的影响较大,温升变化造成动态响应特性、燃油喷射量和喷雾特性发生变化。本体温度为200℃时的GDI喷油器各项关键性能参数与25℃时的相比,其动态响应时间延长了19.08%,燃油喷射量的线性范围收缩了13.7%,喷雾贯穿距离缩短了15.6%。

According to the coupling relationship among subsystems, the bulk temperature rising rules of GDI injector and the effects of temperature rising on comprehensive performance are investigated by means of mathematical modeling and experiment. The results show that, the temperature rising rate of GDI injector increases quickly after powering up, and the factor of the temperature rising is affected by the drive current, drive pulse width and fuel pressure. Due to the temperature rising, the dynamic response characteristics, injection quantity and spray characteristics are changed. Compared the key performance parameters of GDI injector at the bulk temperature of 200 ℃ and 25 ℃, it is found that at the bulk temperature of 200 ℃, the dynamic response time is prolonged by 19.08%, linear range of fuel injection quantity has shrunk 13.7%, spray penetration is shortened by 15.6%.