The experiment results of spark ignited turbulent premixed combustion of CH4-Air Charge in a constant volume bomb have been presented and analyzed.Some valuable conclusions have been drown out,such as at the period of initial flame kernel development,there exits a minimum of flame propagation speed,and the kernel radius corresponding that time is approximately equal to the turbulent integral scale.The increase of turbulence intensity （u'＜1.8m／s） leads to increase of the instantaneous burning rate,decrease combustion duration,increase of relation slow combustion period and decrease of relation main combustion period,this is the essential reason that to organize turbulence in SI engine to improve thermal efficiency.Furthermore,in this paper also presents the miss fire ratio under different electrode gaps in turbulent combustion and indicates reducing the heat transfer form flame kernel to electrode is an important measure to decrease the miss fire ratio.%给出在定容燃烧弹中火花点燃CH4-空气充量进行湍流预混合燃烧的试验结果并进行了分析,得到一些有价值的结论:如在火核起始发展期中存在一个最小火焰传播速度,此时的火核半径与湍流积分长度标尺大致相等,增加湍流强度(u'＜1.8m/s),瞬时燃烧率增加,燃烧持续期缩短,相对缓燃期增加,相对主燃期缩短,这是组织湍流可以提高火花点火发动机热效率的主要原因.此外本文还给出不同间隙的失火率并指出减少火核向电极传热是减少失火率的主要措施.
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