# Stability Evaluation of a Simplified Reclaimer Using Fluid-Structure Interaction
## 3 Results
Despite the reduced geometric detail, the simplified model facilitates a longer simulation period and allows for the examination of steady-state behavior under various wind speed conditions, expanding beyond the singular condition examined in the complex model. From the first of the six results for the simplified model corresponding to the 36 m/s wind speed, it is clear that there is a difference in the flow separation and wake region when compared to the complex model. This could be attributed to the FSI effects and the model's capacity to account for structural deformations, which are not considered in the CFD-only approach of the complex model. Figure 9 presents a visualization of the upper region of the reclaimer. It can be noticed that the mast plays a more important role in the velocity distribution than the boom, because, even with similar areas, the velocity in the boom is more distributed. The sizes of the recirculation zone and the velocity magnitudes in the lateral view were similar. Upon examining the results from both the complex and simplified models of the reclaimer from the superior and lateral views, distinct observations can be made regarding the fluid flow characteristics and structural interactions. For the complex model (Figure 10), which has been analyzed solely under computational fluid dynamics (CFD) at a wind speed of 36 m/s, the visual results indicate detailed flow patterns around the structure. Figure 8: Lateral velocity field—XY Plane—complex CFD model. Figure 9: Top velocity field—XZ Plane—simplified FSI model. The superior view particularly shows the wake region's intricate structure and how the wind interacts with the fine geometrical features. The simplified model, evaluated using fluid-structure interaction (FSI) analysis, exhibits a more generalized flow pattern. This is expected due to the reduced geometric details; however, the FSI approach provides additional insights into the structural response to the wind loading, which is absent in the CFD-only approach. It is worth noting that the FSI results represent a range of wind speeds, which allows for a broader understanding of the dynamic behavior of the structure under varying conditions. Comparing the first result of the simplified model at the same wind speed of 36 m/s as the complex model, we can observe that while the complex model shows more localized flow features, the overall pressure distribution trends remain consistent between the two models. The simplified model, due to better element quality, likely offers more reliable insights into the overall structural behavior, despite the lack of granularity in the flow details. Figure 11 shows the streamlines on a transversal plane. The recirculation patterns observed can also be seen with the streamlines and the vorticity colormap, with red when the recirculation is higher and blue when the flow is linear. It is worth mentioning that due to the reduction of the airflow area, the air reaches the reclaimer with velocities higher than the free current, which might increase the pressure gradient and aerodynamic forces, increasing the probability of failure by stabilization. The results showed more intense vorticity at higher wind speeds, caused by an increase in the displacement of the reclaimer and an increase in the velocity gradients in the boundary layer next to the reclaimer. The format and size of the vortices after the reclaimer were similar for all wind speeds, but distinct magnitudes and thicknesses were observed. The streamline and vorticity patterns depicted in the CFD results for both the complex and simplified models of the reclaimer structure offer insightful contrasts. In the complex model, which only incorporates CFD and is limited to a single wind speed of 36 m/s, the streamlines exhibit pronounced interaction with the structure, demonstrating intricate patterns of flow separation and recirculation zones (Figure 12). Figure 10: Top velocity field—XZ Plane—complex CFD model.