Abstract: Floating ring seals are used in the turbopump of liquid rocket engines to prevent the leakage between the chambers with high-pressure drops. To investigate the dynamic characteristics and the lock-up position of the floating ring seal， a test rig is developed in present study and the structure of the test rig and the experiment procedure are detailed in this study. The test results show that the hydrodynamic force in the seal clearance pushes the floating ring seal to approach the rotor， and the rotor whirling motion makes the floating ring seal close to the rotor whirling center. Under the constant pressure drop， the whirling amplitude of the rotor determines the lock-up ability of the floating ring seal， and the lock-up position depends on the trainset process of the variety for the pressure drop and the rotor vibration. In the test， the minimum distance between the lock-up position and the rotor whirling center is smaller than 10μm.

Key words: Floating ring seal；Lock-up position；Vibration；Rotor

摘要： 浮动环密封被应用于液体火箭涡轮泵中，阻隔高压工质的泄漏。为了研究浮动环密封的运动特性和自锁位置的分布规律，开展试验研究，详细地展示了试验装置的原理和试验步骤。试验结果表明，间隙流体激励推动浮动环密封向转子靠近，转子的涡动运动使浮动环密封更加靠近转子涡动中心。压差恒定时，转子振动幅度决定浮动环密封能否自锁，自锁位置依赖于压差、转子振动的变化过程。试验中，自锁位置距离转子涡动中心的最小距离小于10μm。

关键词: 浮动环密封; 锁死位置; 振动; 转子