Page 90 - IJAMD-1-3

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

By integrating the equation over the number of cycles, the experimental studies typically focus on simulating
total crack growth can be predicted using Equation XII: high-temperature, high-velocity gas flows, replicating
particle impacts, and measuring the subsequent material
N f C ∆ ( . K) m degradation. These experiments offer empirical data on
i ∫
a = a + (XII) erosion rates, surface damage, and structural integrity,
f
which help refine computational predictions and guide
N i dN
where a is the initial crack length; a is the final crack the development of more erosion-resistant materials
f
i
length before failure; and N and N are the initial and and protective coatings. 41,58,78 This section explores the
i
f
final number of cycles, respectively. Using the Paris Law, significant contributions of experimental research,
engineers can achieve the following: detailing methodologies, findings, and their implications
• Identification of high-risk zones: Crack growth for turbine blade durability and performance.
predictions help pinpoint regions on the blade most Hamed et al. conducted an extensive computational
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susceptible to failure, such as leading edges and research initiative, which was dedicated to the comprehensive
trailing edges. analysis of surface degradation within turbine vanes and
• Material selection: Materials with lower values of C blades, specifically attributable to the impingement of solid
and m exhibit slower crack growth rates, making them particulate matter. Leveraging a computational framework,
more resistant to fatigue-induced failure. Hamed et al. were able to predict, based on meticulously
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• Proactive maintenance: The model enables predictions computed particle trajectories, the emergence of a localized
of the remaining useful life of a blade, allowing region characterized by heightened erosion levels along
for timely maintenance or replacement before the vane’s leading edge. Furthermore, the research findings
catastrophic failure occurs. elucidated a discernible trend wherein the erosion intensity
• Design improvements: The insights gained from crack progressively intensified along the pressure surface,
growth analysis inform design modifications, such culminating in a notable elevation of erosion effects as the
as adding erosion-resistant coatings or altering blade trajectory approached the trailing edge. This insightful
geometry to reduce stress concentrations. investigation significantly contributes to the nuanced
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The Paris Law bridges the gap between material fatigue understanding of the intricate erosion mechanisms
theory and practical applications in turbine blade design. prevalent within high-velocity and solid particle-laden
Material fatigue occurs due to the progressive weakening environments, thereby providing valuable insights crucial
of a material under cyclic loading, which is analogous for the development of robust protective measures and
to the repeated particle impacts experienced by turbine advanced material solutions for turbine components.
blades. By quantifying the relationship between cyclic
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stresses and crack growth rates, the Paris Law highlights Taherkhani et al. conducted an extensive investigation
the importance of understanding and mitigating fatigue employing the finite element method to elucidate the
effects to enhance the durability and safety of turbine influence of both particle velocity and particle diameter
components. The inclusion of the Paris Law in Section 3.6 on the erosion rate experienced by a smooth surface. The
underscores its critical role in predicting and mitigating research findings illustrated by Taherkhani et al. clearly
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blade failure caused by repeated particle impacts. By demonstrate the substantial impact of these parameters
providing a quantitative framework for crack growth on the erosion phenomenon. Notably, Taherkhani et al.’s
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analysis, the Paris Law enables engineers to develop study encompassed a comprehensive exploration of
fatigue-resistant designs, select appropriate materials, and particle velocities spanning the range of 100 – 500 m/s,
implement proactive maintenance strategies, ultimately alongside particle diameters ranging from 1 to 5 mm.
extending the operational life of turbine blades. Through the implementation of a numerical approach, a
direct correlation between particle velocity, diameter, and
4. Experimental studies the resultant erosion rate was established. Furthermore, the
Experimental investigations play a crucial role in researchers delved into the intricate dynamics associated
advancing our understanding of erosion-induced failures with suspended solid particles within gas turbine flows,
in gas turbine blades. While computational models and offering critical insights into the consequential material
theoretical frameworks provide valuable insights into the degradation of blade surfaces induced by the impingement
mechanisms of erosion, real-world testing is essential to and interaction of these particles. Their research serves
validate these models, assess material performance, and as a pivotal contribution to the nuanced understanding
identify key factors influencing erosion in operational of erosion dynamics within complex high-velocity
environments. 25,29,36 In the context of gas turbines, environments, facilitating the development of tailored

Volume 1 Issue 3 (2024) 84 doi: 10.36922/ijamd.5188