Loading...
Please wait, while we are loading the content...
Similar Documents
Turbulence effect on crossflow around a circular cylinder at subcritical reynolds numbers
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Saharon, D. B. Sadeh, W. Z. |
| Copyright Year | 1982 |
| Description | An investigation of the effect of freestream turbulence on the flow around a smooth circular cylinder at subcritical Reynolds numbers from 5.2 x 10 to the 4th power to 2.09 x 10 to the 5th power was conducted. Measurements show that the interaction of incident turbulence with the initial laminar boundary layer: (1) modifies the characteristics of the mean surface pressure distribution; (2) induces an aft shift in the separation point ranging from 5 to 50 beyond the laminar separation angle of 80 degrees; and, (3) reduces the mean drag coefficient to values between 97 and 46% of its nearly constant laminar counterpart. The extent of these changes depends on the particular Reynolds number background turbulence combination. These results demonstrate that a boundary-layer flow similar to that found in critical, supercritical and/or transcritical flow regimes is induced by turbulence at subcritical Reynolds numbers and, hence, the effect of turbulence is equivalent to an effective increase in the Reynolds number. The change in the nature and properties of the boundary layer in the subcritical regime, consequent upon the penetration of turbulence into it, is in agreement with the model proposed by the vorticity-amplification theory. |
| File Size | 8158938 |
| Page Count | 154 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19830005116 |
| Archival Resource Key | ark:/13960/t7dr7pc78 |
| Language | English |
| Publisher Date | 1982-11-01 |
| Access Restriction | Open |
| Subject Keyword | Fluid Mechanics And Heat Transfer Turbulence Turbulent Flow Stagnation Flow Reynolds Number Fluid Flow Cylindrical Bodies Turbulent Boundary Layer Flow Visualization Circular Cylinders Boundary Layer Flow 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 |
