CAJ | 학술논문

组合转子作为燃气轮机等的核心部件，其性能退化机理并不明确，揭示其性能退化机理并有效地进行性能退化评估对燃气轮机等长期安全运行具有重要意义。为此，从结构损伤导致性能退化的角度出发，分析拉杆裂纹引起的组合转子性能退化特性。分别建立了组合转子有限元模型和弯曲、扭转刚度模型，利用有限元模型对拉杆上含初始裂纹的组合转子进行裂纹扩展分析，得到拉杆裂纹扩展速率；利用弯曲和扭转刚度模型分析了不同深度的裂纹对组合转子振动的影响，得到组合转子固有频率随裂纹尺寸的变化规律；并提出了衡量由微裂纹导致的组合转子性能退化的度量指标，实现了拉杆裂纹引起的组合转子性能退化的定量评估。研究表明：随着拉杆裂纹尺寸的增大，裂纹的扩展速率变快；拉杆裂纹的存在对组合转子的弯振影响较大，对扭振影响相对较小。
조합전자작위연기륜궤등적핵심부건，기성능퇴화궤리병불명학，게시기성능퇴화궤리병유효지진행성능퇴화평고대연기륜궤등장기안전운행구유중요의의。위차，종결구손상도치성능퇴화적각도출발，분석랍간렬문인기적조합전자성능퇴화특성。분별건립료조합전자유한원모형화만곡、뉴전강도모형，이용유한원모형대랍간상함초시렬문적조합전자진행렬문확전분석，득도랍간렬문확전속솔；이용만곡화뉴전강도모형분석료불동심도적렬문대조합전자진동적영향，득도조합전자고유빈솔수렬문척촌적변화규률；병제출료형량유미렬문도치적조합전자성능퇴화적도량지표，실현료랍간렬문인기적조합전자성능퇴화적정량평고。연구표명：수착랍간렬문척촌적증대，렬문적확전속솔변쾌；랍간렬문적존재대조합전자적만진영향교대，대뉴진영향상대교소。
Revealing the mechanism of performance degradation and assessing the degradation de-gree of a combined rotor ,one of the main parts in engine ,are important to maintain the engine for long-term safety operation .Performance degradation characteristics of combined rotor were discussed ,from the perspective view of performance degradation caused by rod crack .Finite ele-ment model ,bending stiffness model and torsion stiffness model of the combined rotor were es-tablished .The crack extension rate of the rod was gotten by using the finite element model .Al-so ,the influence of different depth of crack to the vibration on combined rotor was analyzed using the bending and torsion stiffness model to obtain the relations between natural frequency and crack size .Then ,the measurement of performance degradation which was caused by micro cracks was put forward ,and the assessment of performance degradation was completed as well .The re-sults showed that the micro crack extension rate got faster when the size of crack increased and the rod crack made much effect on the bending vibration of the combined rotor comparing with the torsional vibration .