Counter-rotation of dual-brush disc, high pressure which can stubborn stains on the ground.
双刷盘相互旋转，高强压力，可清洗顽渍地面。
2
For co-rotation and counter-rotation in which the centrifugal force dominates the flow, the secondary flow in a rotating helical pipe has the same direction with that in a stationary one.
对于正旋转和离心力占优的负旋转，二次流速度的方向和静止的情况相同；
3
About two thirds of viewers were able to reverse the direction of rotation from clockwise to counter-clockwise or vice-versa.