Inelastic stress analysis and failure prediction of the turbine housing in engine motoring tests

In order to predict the thermomechanical failure of the turbine housing, it is essential to consider temperature-dependent inelastic materials undergoing thermal cyclic loads and to obtain the transient temperature distributions. This paper presents the analysis methods to calculate the thermal stresses and the plastic strain ranges for prediction of the fatigue life. The presented work is based on the engine motoring mode test that is commonly used for accelerated engine endurance tests. The results showed that the localized critical regions coincided well with the crack locations identified on the basis of a thermal shock test. The plastic strain values were predicted to lie within the range 0.216-0.396% corresponding to a range of 628-1450 cycles for 1600 target cycles.