基于阻塞流动调控以提载控漏的超临界CO2干气密封螺旋槽参数OA

In order to solve the common problem of simultaneous increase in opening force and leakage rate in the optimal design of spiral groove dry gas seals,this study proposed regulating spiral groove parameters to induce choked flow at the exit of sealing end faces,thereby achieving end face leakage control while enhancing gas film load-carrying capacity.This paper used the finite difference method to solve the pressure and temperature governing equations,analyzing the impacts of thermal effects and turbulent effects on the critical choked spiral groove parameters of supercritical CO₂ dry gas seals under various operating conditions,and the design range of critical choked instability film thickness under different structural parameters.The results showed that increasing spiral groove parameters(groove depth,groove-dam ratio,groove-land ratio,spiral angle)enabled the seal clearance exit velocity to reach the local sonic speed at ambient exit pressure.In laminar-isothermal model,increasing rotational speed reduced the critical choked groove depth,groove-dam ratio,and spiral angle.However,in turbulent-adiabatic models,higher rotational speeds corresponded to larger critical choked spiral groove parameters.Increasing inlet pressure reduced critical choked spiral groove parameters.Turbulent and adiabatic effects exhibited a certain synergistic effect,delaying the occurrence of critical choking and featuring wider design intervals for the critical choked instability film thickness.