Effectiveness of Blade Thickness Distribution on the Turbocharger Turbine Aerostatic Performance

Turbocharger turbine blade thickness is restricted by blockage and trailing edge losses and it is exposed to damage due to aerodynamic loads. Proper designing of the blade needs to full recognition of loads on the blade. Therefore, the force from the fluid to the blade should be calculated. Although, thickening the blade results to the more resistance to fracture and cracks, but it affects the aero-structural performance of each section of the blade differently. So, turbocharger turbine blades are exposed to pulsating flow which should be considered in thickness distribution selection. This article reports a comprehensive fluid-solid interaction study of the turbine blades with different thickness distribution which could beneficially investigates the effect of each part thickness on the aerostatic efficiency. Leading edge and trailing edge thickness, maximum thickness and its location, trailing edge shape, hub, and tip blade thickness were the variables which their effects were investigated. Using dual turbocharger turbines leads to lower dissipation of kinetic energy of pulsating charge from the engine. In such turbines, each sector of rotor accepts a different charge from upper and lower entries. The flow distribution of every passage is the difference from the others. Therefore, to the evaluation of the flow, modeling of the entire turbine is needed. 3D CFD model in ANSYS CFX for fluid side and an FEA model in ANSYS Static Structural module for the blade structural responses were used then the results were coupled. Validation was performed by reference to experimental data carried out in imperial college London on a dual turbocharger turbine.