**7. Conclusion**

In this work, a two-dimensional modeling of the tube erosion test was carried out to predict the erosion phenomenon within hydraulic structures. Unlike, the first models produced by several authors, which are essentially one-dimensional and the two-dimensional modeling of this phenomenon showed that the tangential shear stress along the interface wall between the water and the body of the structure is not uniform. By applying a linear erosion law, we were able to predict nonuniform erosion along the entire length of the interface.

The study of the effect of clay concentration showed that it has a very significant effect on the evolution of wall shear stress, and therefore, in turn, affects the surface erosion that develops at the soil sample fluid interface, particularly at the end of the hole outlet where it is at its maximum. The results obtained have enabled us to understand qualitatively why the eroded profile of the hole wall, as observed during the HET experiment, is not uniform.
