关键词: 涡流槽密封, 预旋比, 泄漏特性, 气流激振力, 动力特性

Abstract: A new seal structure with vortex groove in the circumferential direction of the sealing inlet was proposed. The theoretical models of traditional labyrinth seal and the new type of vortex groove seal leakage characteristics and dynamic characteristics were established. Based on the model accuracy verification by means of experiments， the leakage characteristics and dynamic characteristics of the traditional labyrinth seal and the new type of vortex groove seal  were compared and analyzed under different inlet/outlet pressure ratios and pre-whirl ratios. The influence mechanism of the new vertex groove structure on the seal leakage and dynamic characteristics was studied. The results show that with the increase of the number of vortex groove， the leakage of vortex groove  seal decreases gradually. Under the same pressure ratio， the difference between the leakage of the new seal with different number of vortex grooves increases with the increase of the pressure ratio. When the pressure ratio is as 6， compared with the traditional labyrinth seal， the leakage of the 64 vortex grooves seal is reduced by 3.37%. Under the conditions of high pre-whirl ratio， the tangential airflow force of the seal with different number of vortex grooves is opposite to the direction of rotor vortex， which plays a role in inhibiting rotor vortex， the tangential airflow force increases with the increase of the number of vortex grooves. With the increase of rotor vortex frequency， the cross stiffness of seals with three different number of vortex grooves first decreases to negative value and then increases to positive value. The effective damping of the vortex groove seals is higher than that of the traditional labyrinth seals. The new vortex groove seal may improve the stability of the rotor systems. 

Key words: vortex groove seal, pre-whirl ratio, leakage characteristics, airflow excitation force, dynamic characteristics