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Direct simulation of a self-similar plane wake
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Moser, Robert D. Rogers, Michael M. |
| Copyright Year | 1994 |
| Description | Direct simulations of two time-developing turbulent wakes have been performed. Initial conditions for the simulations were obtained from two realizations of a direct simulation of a turbulent boundary layer at momentum thickness Reynolds number 670. In addition, extra two dimensional disturbances were added in one of the cases to mimic two dimensional forcing. The unforced wake is allowed to evolve long enough to attain self similarity. The mass-flux Reynolds number (equivalent to the momentum thickness Reynolds number in spatially developing wakes) is 2000, which is high enough for a short k(exp -5/3) range to be evident in the streamwise one dimensional velocity spectrum. Several turbulence statistics have been computed by averaging in space and over the self-similar period in time. The growth rate in the unforced flow is low compared to experiments, but when this growth-rate difference is accounted for, the statistics of the unforced case are in reasonable agreement with experiments. However, the forced case is significantly different. The growth rate, turbulence Reynolds number, and turbulence intensities are as much as ten times larger in the forced case. In addition, the forced flow exhibits large-scale structures similar to those observed in transitional wakes, while the unforced flow does not. |
| File Size | 723864 |
| Page Count | 16 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19940030411 |
| Archival Resource Key | ark:/13960/t0jt4kp2h |
| Language | English |
| Publisher Date | 1994-04-01 |
| Access Restriction | Open |
| Subject Keyword | Fluid Mechanics And Heat Transfer Reynolds Stress Turbulence Turbulent Flow Turbulent Wakes Computational Fluid Dynamics Reynolds Number Shear Flow Turbulent Boundary Layer Computerized Simulation Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
