Jet engines operating under dirty conditions are exposed to fine particulate matter such as sand, ash and dirt. This particulate matter can cause severe erosion of compressor blades and when exposed to high temperatures can soften and stick to turbine components in the hot gas path. Large amounts of particles can be ingested at takeoff and landing when engines are running at full power and are in ground proximity.  For an aircraft flying through volcanic dust clouds, particles can also be ingested at cruising altitudes. Operation in these environments has led to serious aircraft accidents due to jet engine failures. The problem of particulate ingestion in the engine has worsened with the use of high bypass ratio turbofan engines . To accurately predict the extent of damage to the turbine vane, it is important to identify and understand the underlying physical processes that lead to deposition.



The objective of this study is to develop a particle sticking model based on energy losses and change in material properties at high temperatures. The study is novel in that it integrates different sources of published experimental data to form a holistic numerical model to predict sand deposition. The deposition model computes the sticking probabilities as a function of particle temperature, impact velocity and particle composition.



Model:





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        Figure 1. Sticking Probability vs Temperature



Validation:

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                  Figure 2. Heat transfer calculations for validation case for jet impingement with particles





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                        Figure 3. Particle Transport for validation case for jet impingement with particles



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All the details are not presented on the website due to copyright and proprietary issues.