A simulation based analysis for enhancement of performances of turbine blades in turbo jet engines with thermal barrier coatings (TBCs)

Abstract

The enhancement of turbine blade performance within turbo jet engines is crucial for prolonged engine life. Amidst various cooling strategies for turbine blades, thermal barrier coatings (TBCs) emerge as a highly effective method. Just as the choice of material for the turbine blade holds importance, so too do the materials comprising TBCs. The current research work aims to pursue finite element-based analyses of turbine blades with TBCs, an almost real complex-shaped geometric model comprising the blade body with a rabbet is essential, the stress generated during TGO growth which is crucial for analysis, to select the substrate from both a thermo-structural and cost perspective. In this research endeavor, TBCs were structured with a substrate, a bond coat (NiCoCrAlY), and a top coat of lanthanum cerate (La₂Ce₂O₇) ceramic layers. A thermally grown oxide (TGO), namely α-Al2O3, forms between the bond coat and the top coat due to the elevated temperatures experienced. Two distinct substrates, Inconel 625 and Titanium-T6 alloy, were meticulously chosen as turbine blade materials. Commencing with NACA 4412 airfoil data, the turbine blade was meticulously designed using CATIA, followed by simulations conducted on ANSYS software through a static thermal structural model. The simulation aimed to determine the optimal top coat/thermally grown oxide (TC/TGO) and TGO/bond coat (TGO/BC) layer thicknesses to achieve minimal equivalent stress and total deformation in the turbine blade. The simulated results revealed that a combination of 400 µm TC/10 µm TGO and 10 µm TGO/100 µm BC provided the lowest equivalent stress and total deformation, thereby offering valuable insights for the current research.

Keywords:

• Turbojet engine
• turbine blade
• TBC-thickness
• bond coat
• TGO
• Topcoat

Acknowledgment

The authors express their gratitude to Rajneesh Kashyap, Senior Research Fellow at IIT Delhi, for generously providing access to simulation software.

Disclosure statement

No potential competing interest was reported by the authors.

Additional information

Funding

The entire research was conducted without any external funding, entirely borne by the authors.