Improved rain erosion protection for multi-spectral ZnS

In this work, the resistance and deformation characteristics of a brittle material against rain erosion are examined by using the non-linear, explicit software LS-DYNA. The water jet with varying speeds impinges at 90° on silica float glass plates with different thicknesses. In the simulations, the Arbitrary Lagrangian Eulerian method is used for modelling of the water. In order to analyse the deformations on the brittle material Johnson–Holmquist–Ceramics (JH-2) is used as the material model. Minimum plate thickness (for constant water jet speed) and maximum water speed (for constant plate thickness), which do not cause any damage to the target, are determined depending on the geometry, boundary conditions and assumed failure strain value for erosion. The results are compared with the water-hammer pressure.

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Constitutive model of confined concrete with stirrups by acid rain erosion

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/643/1/012026 ◽

2021 ◽

Vol 643 ◽

pp. 012026

Author(s):

ZHENG Yue ◽

ZHENG Shansuo ◽

LIU Xiaohang

Keyword(s):

Constitutive Model ◽

Acid Rain ◽

Confined Concrete ◽

Rain Erosion

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A Staged Approach to Erosion Analysis of Wind Turbine Blade Coatings

Coatings ◽

10.3390/coatings11060681 ◽

2021 ◽

Vol 11 (6) ◽

pp. 681

Author(s):

David Nash ◽

Grant Leishman ◽

Cameron Mackie ◽

Kirsten Dyer ◽

Liu Yang

Keyword(s):

Computed Tomography ◽

Wind Turbine ◽

Incubation Period ◽

Leading Edge ◽

X Ray ◽

Erosion Testing ◽

Staged Approach ◽

X Ray Computed ◽

Droplet Impacts ◽

Rain Erosion

The current wind turbine leading-edge erosion research focuses on the end of the incubation period and breakthrough when analysing the erosion mechanism. This work presented here shows the benefits of splitting and describing leading-edge erosion progression into discrete stages. The five identified stages are: (1) an undamaged, as-new, sample; (2) between the undamaged sample and end of incubation; (3) the end of incubation period; (4) between the end of incubation and breakthrough, and (5) breakthrough. Mass loss, microscopy and X-ray computed tomography were investigated at each of the five stages. From this analysis, it was observed that notable changes were detected at Stages 2 and 4, which are not usually considered separately. The staged approach to rain erosion testing offers a more thorough understanding of how the coating system changes and ultimately fails due to rain droplet impacts. It is observed that during microscopy and X-ray computed tomography, changes unobservable to the naked eye can be tracked using the staged approach.

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