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一般用热线风速仪或激光多普勒测速仪测量内燃机缸内的湍流运动,并用集总平均法求取湍流运动的平均速度和湍流强度。本文论述了用单循环分析法描述缸内湍流运动的理论,介绍了时间平均和低通滤波两种单循环分析方法,着重讨论了用单循环分析法和集总平均法计算湍流结构参数的差别。分析认为,集总平均法和单循环分析法分别依据湍流分量中包含还是不包含整体速度的循环变动速度分量来描述湍流运动,两种方法结合起来才能更详细地分析湍流运动的规律。
General use of hot wire anemometer or laser Doppler velocimeter to measure the internal combustion engine turbulence in the cylinder, and use the lumped average method to obtain the average turbulent velocity and turbulence intensity. This paper discusses the theory of single-cycle analysis of turbulent motion in a cylinder. Two time-averaged and low-pass filtered single-cycle analysis methods are introduced. The single-cycle analysis method and the lumped averaging method are used to calculate the difference of turbulence structure parameters . The analysis shows that both the lumped and the single-cycle methods describe the turbulent motion according to the components of the turbulent or non-turbulent components, respectively. The two methods can be combined to analyze the turbulent motion in more detail.