论文部分内容阅读
针对某型涡轮增压器旁通放气阀杆断裂故障,对断口进行了分析,确定了放气阀杆断裂为双向弯曲疲劳失效。在此基础上,运用有限元方法对放气阀杆断裂的失效机理进行了分析,并给出了相应的改进措施。研究表明,由于放气阀的一阶固有频率过低,落在发动机振动激励频率范围之内,很容易引起放气阀杆共振而发生疲劳断裂。建议对放气阀杆进行改进设计以提高其一阶固有频率;同时,结合发动机工作剖面,在设计阶段对放气阀进行动态设计。
Aiming at the breakage failure of a type of turbocharger bypass bleed valve stem, the fracture was analyzed, and the failure of the bleed valve stem was confirmed as two-way bending fatigue failure. On this basis, the failure mechanism of deflation valve stem is analyzed by finite element method, and the corresponding improvement measures are given. Research shows that due to the first natural frequency of the bleed valve is too low, fall within the vibration excitation frequency range of the engine, it is easy to cause the exhaust valve stem resonance and fatigue fracture. It is suggested to improve the first-order natural frequency of the deflation valve stem. At the same time, the design of the deflation valve should be designed dynamically at the design stage according to the working profile of the engine.