摘要
对一台四气门单缸发动机进行了改装,以便于应用粒子图像速度仪(PIV)研究其在进气和压缩冲程缸内横截面内湍流积分尺度的演化过程。结果表明在整个过程中,缸内流场y方向的速度分量在x和y方向的两条空间平均积分尺度曲线一下一上,基本相互平行;x方向的速度分量在x和y方向的空间平均积分尺度的变化基本保持重合一致,随曲轴转角增大略有下降的趋势;在进气上止点后150°CA时y方向速度分量对x和y方向的空间平均积分尺度曲线同时跃升到峰值,此时整个流场积分尺度也达峰值,接近4.0mm;y方向速度分量成为影响整个流场积分尺度发展的主导因素。
On a four-valve optical single-cylinder gasoline engine, PIV （Particle Image Velocimetry） was used to study the evolvement of the turbulent ILS produced by the intake-stroke and the compress-stroke on the cross-section in the cylinder. It was analyzed that the two spatially-averaged ILS curves produced by y-direction velocity component along x and y directions remained lower and higher and parallel basically in the whole process. The two ILS curves produced by x-direction velocity component along x and y directions matched each other and felled down much slowly with the increasing of crank angle. At 150°CA the two ILS curves produced by y-direction velocity component along x and y directions reached peak value synchronously, meanwhile, the ILS of the whole flow field also reached peak value, approaching 4.0mm. The y-direction velocity component became the major factor to influence the alteration of the ILS produced by the whole flow field.
出处
《实验流体力学》
EI
CAS
CSCD
北大核心
2007年第1期59-63,67,共6页
Journal of Experiments in Fluid Mechanics
基金
国家自然科学基金(50006008)
关键词
PIV
汽油机
湍流场
积分尺度
分布图
particle image velocimetry （PIV）
gasoline engine
turbulent flow field
Integral Length Scale （ILS）
distribution map
