Predictably,  Figure \ref{203772} shows that the velocity increases in a quasi-linear trend as the screw angular velocity increases. This pattern has been demonstrated in the literature \cite{thoesen2018screw,thoesen2019helically,thoesen2020comparative,thoesen2020revisiting} and serves as a sanity check for the velocity results. It is readily apparent that the velocity is fairly constant with respect to load time, as well as ramp angle.  
    There does not seem to be a significant difference between the wide configurations C1 and C2, which implies that when the pontoons are far apart, the material churn direction has negligible impact on the velocity.. However, an interesting disparity exists between the narrow configurations C3 and C4 where the inward churning configuration C3 attains significantly higher velocities than the outward churning C4. This could potentially be explained by how the front pontoon width changes the position of the front pontoon wake. In the wide configurations, the front pontoons are only slightly narrower than the rear pontoons. As a result, the rear pontoons are constantly engaging in media that has already been churned. Conversely, in the narrow configurations, the front pontoons are almost entirely out of the way of the rear pontoons. When churning inward, the rear pontoons are engaging with essentially undisturbed granular media, and thus produce more thrust force than the outward churning case. This effect is likely also present in the wide configuration, but less impact because the front and rear pontoons are nearly in line with each other. Thus, to achieve the highest velocity, the pontoons should be narrow enough such that rear pontoons are engaging undisturbed media and avoiding the front pontoon wake.

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