Sammendrag
This graduation project is concerned with the preparation of a drop erosion test in the one hand, and the realization of theses erosion tests in a second hand. The preparation of the drop erosion equipment has been followed by the creation of a numerical model in order to facilitate a comparison between different materials.
Findings from this report will interest student working on the specific field of the rain erosion, along those investigating on the numerical method for the polymer study.
Not only the high speed impact between the rain and the blades of offshore wind turbine leads to a loss of output, but makes the substrate vulnerable to damage, which can threaten the whole structure of the blade, and may lead to its failure.
Initially, the principles of wear are presented, and especially the erosion by water droplets. This relies on the Guided Acoustic Shock (GAS) Theory, which is the most important theory for understanding the basic mechanism of liquid impact erosion. Then a presentation of the ways and means to prepare the drop erosion test is presented. It relies on the characterization of the sample, the test equipment, and the particles and particles flow. The experimental data from the standard helicopter test is used as a reference, and aims at developing the numerical model.
Despite the breakdown of the engine that aborted the main tests, the preparation of the drop erosion equipment is encouraging, thanks to a characterisation of the main test parameters.
The development of a numerical model has been done with the software LS-DYNA and has coupled the Finite element method with the Smoothed Particles theory. This has led to two possibilities to study rain erosion. The first possibility deals with a high number of droplets impacting the coating through time. However, the Discrete Element Method (DEM) seems more adapted for this study. The other possibility focuses on a single droplet impact. Finally a method to create a material model for the PU-tape has been initiated with Abaqus, but need to be improved.
Findings from this report will interest student working on the specific field of the rain erosion, along those investigating on the numerical method for the polymer study.
Not only the high speed impact between the rain and the blades of offshore wind turbine leads to a loss of output, but makes the substrate vulnerable to damage, which can threaten the whole structure of the blade, and may lead to its failure.
Initially, the principles of wear are presented, and especially the erosion by water droplets. This relies on the Guided Acoustic Shock (GAS) Theory, which is the most important theory for understanding the basic mechanism of liquid impact erosion. Then a presentation of the ways and means to prepare the drop erosion test is presented. It relies on the characterization of the sample, the test equipment, and the particles and particles flow. The experimental data from the standard helicopter test is used as a reference, and aims at developing the numerical model.
Despite the breakdown of the engine that aborted the main tests, the preparation of the drop erosion equipment is encouraging, thanks to a characterisation of the main test parameters.
The development of a numerical model has been done with the software LS-DYNA and has coupled the Finite element method with the Smoothed Particles theory. This has led to two possibilities to study rain erosion. The first possibility deals with a high number of droplets impacting the coating through time. However, the Discrete Element Method (DEM) seems more adapted for this study. The other possibility focuses on a single droplet impact. Finally a method to create a material model for the PU-tape has been initiated with Abaqus, but need to be improved.