Studies of the Effects of Drag Reduction Due to Plasma Actuation Applied to Aircraft Configurations: (using a simple modification to a Reynolds-averaged Navier-Stokes turbulence model)

摘要

Smart Longitudinal Instability Prevention via Plasma Surface ("SLIPPS") is a novel drag-reducing technology. Wind tunnel tests at the University of Notre Dame show that the use of SLIPPS can provide more than 70% drag reduction in turbulent flat plate boundary layers. A key aspect of this method of drag reduction is that the reduction in drag is 2.5 to 3.0 times as much as the power to the pulsed-DC actuator. Preliminary design methods indicate that significant benefits could be obtained for a variety of aircraft by use of SLIPPS. The current work employs RANS simulations as input for Preliminary Design Analysis. This approach yields a higher confidence in the Preliminary Design Analysis results. ITAC has developed a simple method for estimating the effects of SLIPPS. The simulations include two configurations: one of a long range commercial airliner, and the other similar to an MQ-9 Reaper UAV. Results have largely confirmed the earlier Preliminary Design Method predictions of the benefits of SLIPPS. However, the effect of the reduced boundary layer turbulence on the shock location in transonic flow over wings can lead to performance degradation. Similarly, the dramatic drop in turbulent shear stress due to SLIPPS on wing surfaces can lead to flow separation in some cases. Thus, care must be taken when integrating SLIPPS onto existing vehicles to ensure that it results in net drag reduction. By applying a lower voltage to the actuator, the performance degradation can be avoided. This paper illustrates a clear path to the successful and beneficial application of SLIPPS.