Page 75 - IJAMD-1-3

International Journal of AI for
Materials and Design
Review of gas turbine blade failures by erosion

1.3. Mitigation strategies extending the operational life of gas turbine blades. These

The use of coatings and erosion-resistant materials is advancements also enable more efficient maintenance
33,34
essential in mitigating the effects of erosion. TBCs, which strategies, reducing downtime and operational costs.
consist of multiple layers including bond coats and thermal Erosion mechanisms across turbine blade zones are listed
barriers, help to protect the underlying substrate from and described in Table 4.
extreme temperatures and particle impacts. These coatings 2. Method for predicting and mitigating
reduce the thermal and mechanical stresses exerted on
the blade. 13,30 However, when TBCs begin to wear away erosion
under sustained particle impacts, the underlying material Recent advancements in analytical methods have
becomes vulnerable, accelerating erosion and leading to revolutionized the field of material degradation, specifically
more rapid structural degradation. in addressing challenges such as erosion-induced failures in
Modifications to the geometry of turbine blades can gas turbine blades. 10,12,14 Machine learning (ML) and other
also help minimize erosion. Redesigning the leading advanced computational techniques such as CFD and FEA
edges to reduce the incidence of particle impacts or are now being increasingly employed to enhance predictive
altering the airflow pattern can reduce the rate of erosion, capabilities and provide more efficient mitigation strategies
as highlighted by simulations and studies employing for erosion. Table 5 delineates the methods for predicting
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computational fluid dynamics (CFD) and finite element and mitigating erosion.
analysis (FEA) to predict erosion-prone zones and stress
points. 14,31 Reducing turbulence and optimizing airflow 2.1. ML applications
in these regions helps lower erosion intensity, thereby In recent years, ML has emerged as a powerful tool in the field
prolonging blade life. of material science and mechanical engineering, particularly
In summary, erosion-induced failures in gas turbine in predictive maintenance and failure analysis. 15,36 The
blades result from a complex interplay of mechanical application of ML in gas turbine blade erosion studies has
and environmental factors, including particle impact opened new avenues for improving reliability, extending
characteristics, material properties, and operational operational life, and optimizing maintenance schedules. The
conditions. 13,14,32 By understanding these mechanisms and ability of ML to analyze large datasets and extract complex
the factors influencing erosion, researchers can develop patterns has revolutionized the way engineers approach
more resilient materials, effective coatings, and optimized predictive modeling for gas turbine blade erosion. ML
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blade designs to reduce erosion’s impact, thereby algorithms are becoming invaluable in identifying patterns

Table 3. Influence of particle characteristics on erosion
Parameter Range tested Effect on erosion Key findings
Particle velocity 100 – 500 m/s Higher velocities increase kinetic energy, Erosion severity is directly proportional to particle
causing greater material removal. velocity. 5,6,11
Particle size 1 – 5 mm Larger particles cause deeper pits and Larger diameters exacerbate erosion rates significantly. 3,4,6
more extensive surface damage.
Impact angle 20° – 90° Steeper angles (close to 90°) transfer Leading edges of blades are most vulnerable due to direct
more energy, causing higher erosion. impacts. 8,9,12,13

Table 4. Erosion mechanisms across turbine blade zones

Blade zone Erosion mechanism Key factors Impact on blade performance
Leading edge High-frequency particle High impact angles, high velocity, turbulence Severe material removal, loss of
impingement at the boundary layer aerodynamic efficiency
Trailing edge Flow separation-induced erosion Low impact angles, erratic particle Localized erosion, structural fatigue, and
trajectories, reduced turbulence dissipation eventual cracking
Blade surface Uniform particle impacts with low Lower velocities and impact angles compared Gradual thinning, minor structural
(mid-body) turbulence. to edges degradation
Blade tips Combined mechanical and thermal High gas velocities, elevated temperatures, Accelerated wear, material fatigue, and
erosion and centrifugal forces potential failure

Volume 1 Issue 3 (2024) 69 doi: 10.36922/ijamd.5188