针对增压器涡轮由离心载荷所引起的轮毂疲劳失效模式,基于装甲车辆柴油机耐久性台架考核试验剖面,分析了增压器在不同工况下运行时涡轮转速的变化规律,计算了涡轮轮毂疲劳危险部位的应力历程.通过对涡轮轮毂疲劳强度模拟试验样件的疲劳性能测试,建立了涡轮轮毂疲劳寿命与应力之间的数学模型.在此基础上,研究了涡轮轮毂的疲劳可靠性分析与寿命预测方法,建立了涡轮轮毂疲劳可靠度与失效率计算模型,给出了涡轮可靠寿命确定方法.研究表明,涡轮轮毂的疲劳可靠度随着寿命增加逐渐降低,失效率初期较小,随着寿命增加逐渐增大,然后又逐渐减小.%For the fatigue failure mode of turbocharger turbine hub caused by the centrifugal load, the changes of turbine speed under different turbocharger running conditions were studied and the stress history of turbine critical part was calculated based on the durability test profile of armored vehicle diesel engine. Through the fatigue test of turbine fatigue specimens, the relationship between fatigue life and stress was determined. Then, the methods of fatigue reliability analysis and life prediction were researched, the mathematic model of fatigue reliability and stress for turbine hub was built, and finally the method of determining the turbine life was acquired. The result shows that the reliability of turbine hub decreases with the increase of fatigue life. The reliability is small in the initial failure rate, then increases with the increase of life, and finally decreases step by step.
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