Vortex Wake Control Using Smart Structures Technology

Control of trailing vortex wakes is an important challenge for both military and civilian applications. Ingestion of concentrated vortices in propellers can lead to undesirable noise in submarines, while the encounter of aircraft wakes with following aircraft presents a significant safety hazard that limits capacity at all major U.S. airports. This proposal involves an assessment of the feasibility of mitigating adverse vortex wake effects using aero- and hydrodynamic control surfaces actuated via smart structures technology. This will involve a combined computational/ design analysis effort focused on identifying changes in the spatial and temporal load distribution on lifting surfaces to promote vortex breakdown and other destructive instabilities that can deintensify the vortex wakes of aircraft and submarines. The computational analysis will apply proven tools in a study of the sensitivity of core structure and vortex wake hazard to modifications of the trailing vortex wake, while the design studies will build on modeling tools recently developed for the analysis of aerodynamic surfaces actuated using smart materials. The overall objective will be the identification of a technically feasible system using deflectable surfaces that can address current challenges in vortex wake deintensification through the promotion of altered wake structure. Anticipated Benefits: Vortex wake hazard drives aircraft landing separation at major airports and the delays resulting from excessive spacing cost the US economy several billion dollars annually in lost time and jet fuel. Even relatively modest reductions in current spacing would substantially increase effective airport capacity. In addition, wake alleviation for submarines would help protect the investment in the current fleet of low-noise underwater vehicles.