主喷和预喷参数对高压共轨柴油机高海拔燃烧特性的影响研究

Influence of Main and Pilot-injection Parameters on High Altitude Combustion Characteristics of High Pressure Common Rail Diesel Engine

利用内燃机高原环境模拟试验台,进行了柴油机高海拔燃烧模拟试验,研究了不同海拔下主喷和预喷参数对高压共轨柴油机燃烧特性的影响。结果表明:随海拔升高,滞燃期、最大压升率、放热率峰值上升明显,放热率重心推迟,柴油机动力性及工作噪音恶化。高原条件下,主喷定时、共轨压力、预喷间隔、预喷量等均会对高压共轨柴油机燃烧特性产生不同程度的影响。

The high altitude combustion simulation test of a diesel engine was carried out by using the combustion engine plateau environment simulation test bench. The effects of main and pilot-injection parameters on the combustion characteristics of high pressure common rail diesel engine were studied. The results show that as the altitude increases, the peak values of the retarding period, the maximum pressure increasing rate and the heat releasing rate increase obviously; the center of gravity of the heat releasing rate is delayed, and the dynamic performance of the diesel engine and the working noise are deteriorated. Under the condition of high altitude, the main injection timing, the common rail pressure, the pre-injection interval, the pre-spray volume and so on, all will have different degrees of impact on the combustion characteristics of high-pressure common-rail diesel engine.