利用振动加速度信号对柴油机燃烧始点进行了识别。通过模拟计算的方法分析了缸盖表面振动加速度特征点和燃烧始点的关系,表明缸盖表面振动加速度和缸内压力二次导数具有相似的变化趋势,可利用压缩冲程中振动加速度峰值之前的过零点估计燃烧始点出现时刻。在195型柴油机上进行的台架实验结果表明,以缸内压力信号识别的燃烧始点为参考点,振动加速度识别的燃烧始点偏差在1.5°CA之内,基于缸盖振动加速度识别柴油机燃烧始点是可行的。
Estimating combustion timing in diesel engine by cylinder head vibration acceleration was presented.The correlation between the vibration acceleration and the second derivative pressure was compared based on a 195 diesel engine finite element model.Results showed that the vibration acceleration and the second derivative pressure had the similar trend before the peak pressure,and the combustion timing was supposed to be identified by the zero vibration acceleration at this range.Experiments were conducted on a 195 diesel engine and the results verified that the combustion timing could be determined by the vibration acceleration of cylinder head with the deviation within ±1.5°CA.