COMPUTATIONAL ANALYSIS ON THE USE OF VARIOUS NIMONIC ALLOYS AS GAS TURBINE BLADE MATERIALS

Blade failure is triggering more problems to the gas turbine engines, while being used in airline and jet engines. In this paper, causes of blade failure with respect to various Nimonic alloys is investigated by performing structural and thermal analyses. Using Ansys, both these analyses on turbine blade are carried out, which is utilized for determining equivalent stresses, deformation and thermal stresses by applying different turbine inlet temperatures and pressures. Turbine blade model is prepared using Solid Works. The computational model is then imported to Ansys workbench. Before importing to the solver, the domain is meshed and boundary conditions are applied. Properties like coefficient of thermal expansion and thermal conductivity are given as material conditions. Ambient temperature, rotational speed, inlet pressure and temperature are considered as boundary conditions. For various configurations and alloy materials, deformation, strain and thermal stresses are plotted and analyzed. After thorough investigation, the turbine blade failure region is identified and the trend is compared for different input temperatures and pressures. At the root of the blade, the stresses and strains are found to be more. Of all the materials considered, Nimonic-90 has less deformation and thermal stresses. Nimonic-80A has more equivalent stress, strain and deformation. Out of the other two materials, Nimonic-263 is showing favourable properties than Nimonic-105. However, the values of stresses and strains are comparable. Thus the present work is beneficial in identifying suitable Nimonic alloy as gas turbine blade material in order to avoid the frequent turbine blade failures.