Numerical Calculation of Static Holding Flow of Hydraulic Stepped Cylinder

This study used the Computational Fluid Dynamics（CFD） program CFX5 to calculate the flow in the chamfer holes,exhaust hole and maze to achieve the static holding flow of the hydraulic stepped cylinder.The results indicated that the flow through the chamfer holes was the main part of the static holding flow,which determined the changing rule of the static holding flow with the change of the outer tube position.The flow through the exhaust hole and maze was relatively small,and the effect on the static holding flow was also small.The maximum and minimum static holding flow increased with the increase of temperature,which agreed well with the experimental results.