Simulation studies on the comparison of different superalloys used in gas turbine blades

Abstract

Impingement of gases at high temperature and pressure leads to the development of stresses and deformation in gas turbine blades. Other important characteristics are also getting changed, prompting more problems in gas turbine engines, as they are used in both power generation and transportation. In this work, failure aspects in blades is studied by performing structural analysis, considering superalloys that are used in the industry. Software packages like Solidworks and Ansys are used for modelling, meshing and solving, in order to identify the target variables like total deformation, von Mises stress, strain energy and fatigue. Geomtery of the turbine blade is modelled and after meshing, boundary conditions like pressure, force and rotational speed are enforced. Results are analysed after carrying out the static structural analysis in Ansys work bench. For the superalloy materials chosen, contours and plots are made for all the configurations. Validation of deformation from the present work is done with experiments done earlier, which is in good agreement. Total deformation is more at the tip of the blade. At the root of the blade, the stresses are found to be more. Presence of strain energy is more near the root. Fatigue life contours showed similarity in all the cases. The blade failure region is identified for all the materials under consideration and the trends are compared for different input temperatures. Thus the current work is helpful in recognizing appropriate superalloy to be used in the present day gas turbines and supports the use of GTD 111 as gas turbine blade material.