汽油机的循环变动及其影响因素

Gasoline Engine Cycle-to-Cycle Variations and Their Effect Factors

通过在单缸机上进行的试验和缸内进行的分析,说明了汽油机循环变动主要受约于着火延迟期的长短。那些对着火延迟期有直接影响的因素都影响着循环变动,其中混合气成分(即空燃比)的影响最为明显。混合气偏浓,循环变动明显减小。其他如发动机转速、点火提前角、冷却水温度、压缩比等都不同程度地通过着火延迟期影响着循环变动,从而掌握了降低循环变动的基本要领。

Experiments on single-cylinder engine and analysis of the combustion in cylinder s ow that gasoline engine cycle-to-cycle variations mainly depend on the length of ignition delay. The factors that directly affect the ignition delay all affect the cycle-to-cycle variations. Among these factors, the A/F ratio is the primary one. Cycle-to-cycle variations decrease markedly with richer mixture. Other factors suchas engine speed, spark timing, cool■nt temprature, compression ratio etc have something to do with the cyclic variations. This revelation may serve s a key to minimizing the cycle-to-cycle variations.