Some way into its path - perhaps around the 10 m mark (or at about the position of the wall of defenders) - the ball's velocity dropped such that it entered the laminarflow regime.
在球运行路径的某一点(10米处，或人墙的位置)球的速度下降，使空气在球体表面形成较稳定的层流。
2
This could be done with surfaces that change shape, or by using a system of holes and slots that can be opened and closed as appropriate to create suction that maintains laminarflow.
这将通过改变机翼表面形状，或采用能适当的开启和关闭孔、缝以吸住层流的系统来实现。
3
This paper studies the flow law of the laminar helical flow of the power law fluid and Billgham fluid in eccentric annular space and the determination of the flow state.