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利用缸内三维流场测量装置 ,运用热线风速仪在稳流模拟试验台上研究了四气门直喷式柴油机进气过程的缸内流场特性 ,并与两气门直喷式柴油机进行了比较 ,揭示了四气门直喷式柴油机进气涡流的形成过程及气门开度对其影响的变化规律 .两气门直喷式柴油机进气涡流主要由进气门轴线至气缸轴线附近的强气流产生 ,缸内主涡流出现在进气门下方 ,副涡流较弱 ;四气门直喷式柴油机的进气涡流主要由气缸周边处的强气流产生 ,缸内主涡流出现在两进气道气门的下方 ,随气门开度的增大而增强 ,副涡流出现在远离进气门的一边 ,随气门开度的减小而增强
The characteristics of in-cylinder flow field in a four-valve direct-injection diesel engine during the intake process were studied by the use of a three-dimensional flow field measuring device in a steady flow simulation test rig using a hot wire anemometer. Compared with two-valve direct injection diesel engine, The forming process of intake vortex flow and the variation of valve opening degree of four-valve direct-injection diesel engine are revealed.The intake vortex of two-valve direct injection diesel engine is mainly generated by the strong airflow around the axis of intake valve to the cylinder axis, The main vortex appears below the intake valve and the vortex is weak. The intake vortex of the four-valve direct injection diesel engine is mainly generated by the strong airflow around the cylinder. The main vortex in the cylinder appears below the two intake valves. Increased valve opening increases and vice vortex appears in the side away from the intake valve, with the valve opening is reduced and enhanced