*3.6. Validation*

The study was validated by reproducing the numerical experiment of Nguyen [28], where a wet erosion test rig was used to discharge and project sand particles. A stainless steel plate specimen with a 196 Vickers' hardness was used for the experiment. The parameters of the experimental setup are shown in Table 5.

**Table 5.** Details of the experimental setup for the validation.


The results shown in Figure 6 were obtained from the numerical assessment. A satisfactory agreement between the erosion pattern and the results of the experimental and computational tests was observed.

The chart shows the material removal in the specimen caused by sediment erosion, where the center of the chart is aligned with the center of the nozzle. An inverted "W" shape was obtained for the erosion pattern caused by an expected stagnation point in the zone directly below the nozzle. The highest erosion rate was observed right outside this stagnation zone.

**Figure 6.** Numerical and experimental material removal in the test specimen (5 min impingement).
