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本文报导了采用激光多普勒测速仪（ＬＤＡ）首次在实机上对柴油机涡流室内空气运动规律测试的研究结果。研究表明：涡流室内涡流在一定的半径范围内是刚体涡流，在涡流室周边区域可近似看作势涡流。涡流室连接通道处气流速度最高，涡流室上流侧区域气流速度较下流侧区域高，上部区域气流速度较涡流室下部高，涡流室中心附近气流速度最低。涡流室中心附近湍流强度较高，涡流室上流侧湍流强度明显高于下流侧，上部区域高于下部区域。在此基础上建立了吊钟型涡流室内空气运动的实用型简化数学模型。该模型考虑了曲轴转角、涡流室内不同区域、转速等因素对空气运动的影响，对进一步分析和模拟涡流室式柴油机的燃烧过程具有重要意义。
This paper reports the results of the first test of the air movement in a diesel vortex chamber by a laser Doppler velocimeter (LDA). The results show that the eddy current in a vortex chamber is a rigid body vortex within a certain radius and can be approximated as a potential vortex flow in the peripheral region of the vortex chamber. The airflow velocity was the highest in the vortex chamber connecting channel, the airflow velocity in the upper stream side of the vortex chamber was higher than that in the downstream stream, the velocity in the upper area was higher than that in the lower vortex chamber, and the lowest in the vortex chamber. The turbulent intensity near the center of the vortex chamber is higher, the turbulence intensity at the upstream side of the vortex chamber is obviously higher than that at the downstream side, and the upper area is higher than the lower area. On this basis, a practical and simplified mathematical model of indoor bell-type vortex indoor air movement is established. The model takes into account the influence of the crank angle, the different regions in the vortex chamber and the rotating speed on the air movement, which is of great significance for further analysis and simulation of the combustion process of the vortex chamber diesel engine.