Limit cycle oscillations (LCO), an aeromechnical instability similar to flutter, have affected high performance aircraft, like the F-16 and F-18, for years. The phenomena causes a lateral motion of the cockpit that makes performance of typical tasks difficult. To better understand the nature of LCO and why high performance aircraft were typically afflicted, a series of of wind tunnel experiments were conducted. The experiments were designed to investigate the flow field around a straked, semispan delta wing and monitor the changes as the semispan was pitched in an oscillatory fashion. The oscillations were intended to mimic LCO. By understanding the flow field around an oscillating wing, the fluid force that causes the motion could be discerned. The wind tunnel experiments and recent computational methods have focused on tracking shock movement along the top surface of the semispan to confirm the presence of shock-induced trailing edge separation, one possible LCO driver. For the current effort, a computational model was developed to compare to the results of the wind tunnel tests and discern more information about the flow features around a straked, delta wing. The computational model was constructed using the Cartesian overset capabilities of the CREATE-AV™ fixed wing fluid dynamics solver Kestrel. The geometry of the model was based on the original wind tunnel model and an Euler model that was recently developed to investigate the same experiments. The results indicate that shock-boundary layer interaction is an important physical driver of shock motion along the surface of the model. For the two cases tested, significantly more movement was observed at the lower angle of attack case, with about a 16% difference between the two in some locations along the wing.
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