Project Details
Description
the tips of vortex generators, fences, turbine blades, and similar aerodynamic devices which appear on Navy aircraft. In particular, these tip vortices can rapidly decay or suddenly breakdown and produce dangerous unsteady pressure loads and large-scale flow separation. The stability properties of tip vortices are strongly influenced by the vortex circulation strength in conjunction with the local Reynolds number, Mach number, adverse pressure gradient, andfreestream turbulence (FST) level. Currently, the dynamic interactions between these factors are poorly understood. For example, it is unclear whether or not turbulence entrainment has a stabilizing or destabilizing effect on a wall-bounded vortex, and furthermore, how the stability properties in this case are affected by the strength of the adverse pressure gradient. In order to address this issue, we propose a joint computational and experimental study of a model tip vortex problem over a wide range of flow conditions. As part of the proposed study, we plan to develop a high-order, enrichment-based, wall-modeled, large eddy simulation (LES) framework for simulating high Reynolds number, non-equilibrium, compressible flows. In addition, we plan to develop a complementary set of wind-tunnel models with high-resolution diagnostics for lowspeed and high-speed flows. Finally, we intend to develop an analytical framework which will include linear stability theory for identifying the orientations and frequencies of disturbances which facilitate vortex breakdown, and a regime map for identifying potentially unstable regions of the flight envelope. In each case, we will ensure that the outcomes of the research are available to scientists and engineers at the Navy and its associated industrial partners. In thelong-term, we anticipate that our newly developed insights into tip vortex decay and breakdown mechanisms will enable the design of future stealth fighter jets (with more aggressively designed inlets), transport and reconnaissance aircraft (with more aerodynamically efficient wings and control surfaces), and propulsion systems (with more efficient compressor and turbine sections).
Status | Active |
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Effective start/end date | 2/3/21 → … |
Funding
- U.S. Navy: $543,713.00