重型电控共轨柴油机高海拔(低气压)热流量分配试验研究

Experimental research of heat flow distribution in heavy-duty common-rail diesel engine at high altitude(low atmospheric pressure)

中文关键词: 重型电控共轨柴油机  高海拔(低气压)  热流量分配  试验研究

英文关键词: Heavy-duty common-rail diesel engine  High altitude(Low atmospheric pressure)  Heat flow distribution  Experimental research

中文摘要:

      针对柴油机在高原环境条件下工作时存在热负荷增大、冷却系统散热能力不足等热平衡问题，利用自行设计的重型电控共轨柴油机高海拔（低气压）热平衡模拟试验系统，开展了不同海拔(大气压力)下柴油机全负荷工况热平衡试验研究，分析了不同海拔（大气压力）对柴油机热流量分配的影响规律。结果表明：随着海拔的升高，转化为有效功的热量和排气带走的热量均不断下降，而冷却液带走的热量和余项损失均不断增加。海拔每升高1 km，转化为有效功的热量平均下降了11.1kW（约3.8%），且低转速区下降幅度比高转速区大；排气带走的热量平均下降了13.3kW（约4.6%），且高转速区下降幅度比低转速区大；冷却液带走的热量平均增加了8.0kW（约5.3%）；余项损失平均增加了16.4kW（约40.1%）。当海拔超过3 km时，热流量分配的变化幅度更加明显。

英文摘要:

      Aiming at the heat balance problem of diesel engine working under plateau environment conditions，such as increasing of heat load and decreasing of cooling capacity in cooling system, an experimental research of diesel engine heat balance under full load working condition at different altitudes (atmospheric pressure)was carried out via self-designed high altitude(low atmospheric pressure)heat balance experimental system for heavy-duty common-rail diesel engine. The effect of altitudes(atmospheric pressure)on the heat flow distribution in diesel engine was analyzed. The results show that with the increase of altitude, both the heat converted into the useful work and the heat removed from exhaust air decrease, while the heat carried away by coolant and the remainder heat loss increase. With the altitude increasing every 1 km, the heat converted into useful work decreases 11.1kW（3.8%）on average , and the decrease in low speed area is larger than that in high speed area; the heat removed from the exhaust air decreases 13.3kW（4.6%） on average, and the decrease in high speed area is larger than that in low speed area; the heat carried away by coolant increases 8.0kW（5.3%）on average; and the remainder heat loss increases 16.4kW（40.1%）on average. Moreover, the change of heat flow distribution is more obvious when the altitude above 3 km.f above 3 km, the change of heat flow distribution is more obvious.