Experiment of static and dynamic characteristics of spiral grooved seals
Experiment of static and dynamic characteristics of spiral grooved seals
复制标题
作者：
T. Iwatsubo;B. Sheng;M. Ono
对六种螺旋槽密封的泄漏量和动态特性进行了试验研究。在相同的名义间隙、槽脊长度和槽深条件下，主要研究了螺旋角对密封性能的影响。测量了预涡速度、密封进出口压差、涡动幅值、涡动速度和转子转速等参数下的动态特性。结果还表明，泄漏量随螺旋角的增大而增大，但随着转速的增大，较大螺旋角密封的泄漏量迅速下降。光滑定子（SS）/光滑槽转子（SGR）密封的泄漏量下降速度快于螺旋槽定子（SGS）/光滑转子（SR）密封。研究发现，沿螺旋角方向的流动可以产生周向流动，这种周向流动起到负漩涡的作用。沿着螺旋角方向的流动可以产生周向流动，这种周向流动起到负漩涡的作用。在当前的螺旋角范围内，存在一个最佳螺旋角，在该螺旋角下密封对转子稳定性有相对积极的影响。与SGS/SR密封相比，SS/SGR密封对转子稳定性的影响更差。
The leakages and the dynamic characteristics of six types of spiral grooved seals are experimentally investigated. The effect of the helix angle of the seal is investigated mainly under the condition of the same nominal clearances, land and groove lengths, and groove depths. The dynamic characteristics are measured for various parameters such as preswirl velocity, pressure difference between inlet and outlet of the seal, whirling amplitude, whirling speed, and rotating speed of the rotor. The results are also compared with leakage increases with the increase of the helix angle, but as the rotating speed increases, the leakages of the larger helix angle seals quickly drop. The leakage of the smooth-stator (SS)/smooth-grooved rotor (SGR) seal drops faster than that of the spiral-grooved stator (SGS)/smooth-rotor (SR) seal. It is found that a circumferential flow can be produced by the flow along the helix angle direction, and this circumferential flow acts as a negative swirl. For the present helix angle range, there is an optimum helix angle with which the seal has a comparatively positive effect on the rotor stability. Compared with the SGS/SR seals, the SS/SGR seal has a worse effect on the rotor stability.