摘要
缸内混合气温度和浓度分布,对发动机稳定运行,保障行车安全、避免发生路上人身伤亡或财物损失有重要影响。为了测量发动机缸内混合气的温度和浓度分布,建立了利用单波长激光诱导双示踪剂产生双荧光的测试系统,并拍摄了不同混合气温度、压力和浓度下的荧光图像,获得了不同示踪剂的荧光强度及其比值随温度、压力和浓度的变化关系,并将标定结果用于光学发动机缸内混合气的温度和浓度测量。结果表明,荧光强度及荧光比值均受到环境的压力、温度和混合气浓度的影响。利用PLIF方法得到的片光源穿过的缸内水平截面内的平均温度与用气缸压力计算的同一曲轴转角下的缸内平均温度变化趋势相同,两者之间的差值随着活塞上行而逐步减小。
The temperature and concentration distribution of in-cylinder mixture have great impact on the steady op- eration of engine, keeping the driving safety, and avoiding road injury and property loss. In order to measure the in-cylinder distribution of mixture temperature and concentration, a calibration system was established with the application of single wavelength laser to simultaneously excite dual tracers and generate dual fluorescence with different wavelengths. Fluorescence images were taken under different mixture temperature, pressure and concentration. The relations among fluorescence intensity of different tracers, fluorescence ratio and mixture temperature, pressure, concentration were obtained to calculate the mixture temperature and concentration in an optical engine. The results showed that the fluorescence intensity and the fluorescence ratio are affected by ambient pressure, temperature and mixture concentration. Comparison was made between the weighted average temperature in the plane of laser sheet in the cylinder and the in-cylinder average temperature calculated from engine pressure when the piston is at the same crank angle. The results indicated that the trends of the two temperatures with crank angle are similar. The differences between them gradually decrease as the piston moves towards the top dead center.
出处
《中国安全生产科学技术》
CAS
CSCD
2014年第9期61-66,共6页
Journal of Safety Science and Technology
基金
国家自然科学基金项目(51076113)
国家自然科学基金项目(71173198)
国家“十二五”科技支撑计划课题(2012BAK03B05)
质检公益行业专项(201010262)
关键词
行车安全
激光诱导荧光
示踪剂
混合气
温度
浓度
driving safety
laser induced fluorescence
tracer
mixture
temperature
concentration
