A numerical study is conducted to examine the vortex structure and aerodynamic loading on a unidirectionally revolving wing. Wings with aspect ratios of one, two, and four are simulated, and each wing is shown to generate a stable and coherent vortex system shortly after the onset of the motion. The proximity of the vortex to the surface of the wing promotes a strong region of suction along the leading edge that persists to the mid-span, regardless of aspect ratio. Past mid-span, the vortex lifts off the surface into an arch-type structure as it reorients itself along the tip. The highest aspect ratio wing promotes the development of substructures in the feeding sheet of the leading edge vortex. The origins of these features have been traced back to the eruption of near-wall vorticity underneath the vortex that disrupts the shear layer, causing the feeding sheet to roll-up into discrete substructures. For a fixed root-based Reynolds number of 1,000, the lower aspect ratio wings do not have sufficient spans for these transitional elements to manifest. The leading edge vortex grows proportionally to the distance from the rotational axis, so with higher aspect ratios, the chord-wise extent of the vortex becomes constrained by the trailing edge, leading to saturation of the aerodynamic loads. With AR = 1, the extent of the vortex never reaches the trailing edge, leading to a slight increase of the lift and drag coefficients throughout the motion. The centrifugal, Coriolis, and pressure gradient forces are also analyzed at several span-wise locations across each wing, where the centrifugal and pressure gradient forces are shown to be responsible for the span-wise flow around the suction side of the wing. The Coriolis force is observed to have a contribution at the base of the leading edge vortex directed away from the surface, indicating that Coriolis does not promote attachment of the vortex. As a means of emphasizing the importance of the centrifugal force on a revolving wing, the aspect-ratio-two wing is simulated with the addition of a source term in the governing equations to oppose and eliminate the centrifugal force near the wing surface. The initial formation and development of the leading edge vortex is unhindered by the absence of this force; however, later in the motion, the lifted-off portion of the vortex moves inboard. Without the opposing outboard centrifugal force to keep the separation past mid-span, the entire vortex eventually separates and moves away from the surface resulting in stall.
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