多火花塞点火实现快速燃烧的试验研究

Experimental Study on Achieving Rapid Combustion with Multi-Spark Ignition

使用快速压缩-膨胀机改装的多火花塞点火试验台架,研究了火花塞数目对指示功大小、最高燃烧压力和最大压升率、燃料放热速率及爆震特性的影响。得到结果如下:液压源压力及混合气浓度相同,点火相位从上止点前5~35mm逐渐增大时,指示功先增大后减少,即存在最佳点火相位;随着火花数目的增加,最佳点火时刻后移;多火花塞点火的放热速率、最高燃烧压力和压升率、指示功均比单火花塞点火有明显提升,提升幅度和火花塞数目并不成线性关系;在混合气稀薄时,多火花塞点火对燃烧速率及指示功的提升作用更加明显;随着液压源压力的增大,相同点火相位时,多火花塞比单火花塞点火爆震倾向更加严重。

On a multi-spark ignition experimental platform retrofitted from a rapid compression and expansion machine, the influence of the number of spark plugs on indicated work, maximum combustion pressure, maximum pressure rise rate, heat release rate and knock characteristics was studied. The conclusions are as follows when hydraulic pressure and mixed gas concentration are kept constant, the indicated work increases at first and then decreases with the advancement of the ignition phase from 5 to 35 mm before TDC. There is an optimum ignition time, and it is delayed accordingly as the number of spark plugs increases. The heat release rate, maximum combustion pressure, pressure rise rate and indicated work with multi-spark ignition are significantly higher than those with single spark ignition, and their increase rates are not linear with the number of spark plugs; increased burning rate and indicated work are more obvious in thin mixed gas with more than one spark plug. Multi-spark ignition is more inclined to cause knock at the same ignition phase with higher hydraulic pressure.