Structural analysis of load compressor blade of aircraft auxiliary power unit

Auxiliary power unit is small gas turbine which comprises power section, load compressor and generator system. The present work incorporates stress analysis of impeller blade of the load compressor aircraft APU 131-9A using ANSYS 15. For centrifugal compressor, impeller is main dynamic component. Structural stresses induced in impeller due to combined loading of thermal and inertia forces, affects performance of compressor in terms of efficiency, pressure ratio, service life etc. To explore the effect of this combined loading, structural analysis has been done. Structural analysis of impeller blade gives a vision about critical deformations and critical stresses and their locations. Thermal analysis has also been done to investigate thermal stresses and deformation due to temperature and pressure loads in the blade passage. Both thermal and structural analysis has been done for different materials namely SS 310, INCOLOY 909, Timetal834 and Ti 6-2-4-6. The selection of materials has been done on the basis of strength at high speeds. The results suggest that for particular application of high speed load compressor blade, induced structural stresses are within permissible range throughout the blade only in case of Ti 6-2-4-6.