多工况下内燃机示功图的试验测试与分析

Experimental Study on Indicator Diagram of Diesel Engine under Various Operating Conditions

进行多工况下内燃机示功图的试验测试研究与分析可以对内燃机工作性能进行全面考察。阐述了多工况下示功图测试的基本方法,并结合某柴油机,通过试验对不同负荷、转速条件下的示功图测量结果进行了详细的对比分析。研究结果表明,转速条件一定时,在膨胀做功阶段,高负荷时的缸内压力明显要高于低负荷时的缸内压力,而在其它阶段,不同柴油机负荷条件下缸内压力大小差异不明显。在同种大小负荷程度下,随着转速的增加,缸内最大爆发压力的变化不是很明显。但在同一转速下,缸内最大爆发压力随着柴油机负荷的升高明显增加。

Performance of internal combustion engine under various operating conditions can be investigated roundly by experimentally studying on indicator diagram. Basic method of testing of indicator diagram under various operating conditions is presented here. Combining with a diesel engine, comparing researches on test results of indicator diagram under different operating conditions are carried out. Results show that the cylinder pressure at high load is higher obviously than the cylinder pressure at low load during expansion period when rotate speeds are constant, while it is not evident＊~uring other operating periods. Under the same loading conditions, maximum cylinder pressure＇s changing is not obvious with the increasing of rotator speed. However, it＇s increasing evidently with the increasing of loading under same rotate speed conditions.