CAJ | 학술논문

以转子—轴承—密封系统为对象，建立轴承/密封耦合作用对系统动力特性影响的有限元模型。分别应用有限差分和CFD方法对轴承、密封动力特性系数进行求解。理论研究表明密封对转子不平衡响应的影响主要集中在共振区域。通过在密封入口引入负预旋可以提高系统的稳定性，密封气流力对系统稳定性影响随转速的升高也越来越大。通过选择合适的轴承型式可以补偿密封气流力对系统稳定性带来的不利影响。试验发现随着转速增加，试验转子在5000 r/min附近时开始出现比较明显的半频分量，而且随着转速继续增加，半频分量的幅值变大。密封流体激振力的存在促进轴承内油膜失稳故障发生，影响系统稳定性。
이전자—축승—밀봉계통위대상，건립축승/밀봉우합작용대계통동력특성영향적유한원모형。분별응용유한차분화CFD방법대축승、밀봉동력특성계수진행구해。이론연구표명밀봉대전자불평형향응적영향주요집중재공진구역。통과재밀봉입구인입부예선가이제고계통적은정성，밀봉기류력대계통은정성영향수전속적승고야월래월대。통과선택합괄적축승형식가이보상밀봉기류력대계통은정성대래적불리영향。시험발현수착전속증가，시험전자재5000 r/min부근시개시출현비교명현적반빈분량，이차수착전속계속증가，반빈분량적폭치변대。밀봉류체격진력적존재촉진축승내유막실은고장발생，영향계통은정성。
Finite element model of a rotor-bearing-seal system was set up to study the influence of the coupling effect of bearings and seals on the system characteristics. Finite difference method and CFD method were employed to obtain the dynamic coefficients of the bearings and seals. Theoretical studies show that the seal has a large influence on the synchronous response of the rotor in the resonant region. Negative preswirl at the inlet of the seal tends to improve the system stability. Influence of the seal force on the system stability becomes more and more serious with the increasing of the rotating speed. Results also show that the detrimental influence of the seal can be compensated by using suitable bearings. Test results show that the subsynchronous vibration appears at about 5 000 r/min, and it becomes larger and larger with the increasing of the rotating speed. The existence of the seal force tends to promote the occurrence of instability faults in bearings and affect the system stability.