With the velocity and the pressure of opening valve of hydro-pneumatic spring,throttle aperture design formula of hydro-pneumatic was built,the affection of superposition throttle slices and adjustment gasket thickness on the throttle aperture was analyzed.

The design formula of throttle aperture of hydro-pneumatic spring was established according to the relationship between pressure and flux.

When the floating ring hybrid thrust bearing with the structure of deep and shallow cavity crevice throttle runs in high speed,with the increase of inertia force,the fluid state transforms from laminar flow to turbulent flow.

Characteristics and applications of top gap slit flow at reversed tainter valve on lock with high lift;

This paper put forward some calculation formula of velocity distribution,viscous resistance,frictional coefficient and loss coefficient intransition for interstitial flow between inclined plates in different boundary conditions,which be a reference to theory analysis and calculation.