Turbulent Boundary Layers With Unsteady Injection-SuctionSource: Journal of Fluids Engineering:;1980:;volume( 102 ):;issue: 003::page 364Author:D. T. Tsahalis
DOI: 10.1115/1.3240695Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: The time dependent turbulent boundary-layer equations with a two-layer eddy viscosity model are integrated numerically over a porous flat plate for a steady outer flow and a sinusoidally distributed injection-suction that varies harmonically with time. The dependence of the unsteady wall shear on the frequency and strength of injection-suction is investigated. The present results indicate that the time-averaged skin friction is always larger than the skin friction observed over a nonporous flat plate. Comparison with previous theoretical results indicates that the time-averaged skin friction is always smaller than the skin friction observed over a porous flat plate with steady, simultaneous injection-suction of the same strength. The extension of eddy viscosity models, developed for steady flows, to unsteady flows is discussed.
keyword(s): Suction , Boundary layer turbulence , Skin friction (Fluid dynamics) , Flat plates , Flow (Dynamics) , Eddies (Fluid dynamics) , Viscosity , Turbulence , Shear (Mechanics) , Boundary layers , Unsteady flow AND Equations ,
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| contributor author | D. T. Tsahalis | |
| date accessioned | 2017-05-08T23:09:03Z | |
| date available | 2017-05-08T23:09:03Z | |
| date copyright | September, 1980 | |
| date issued | 1980 | |
| identifier issn | 0098-2202 | |
| identifier other | JFEGA4-26962#364_1.pdf | |
| identifier uri | http://yetl.yabesh.ir/yetl/handle/yetl/93470 | |
| description abstract | The time dependent turbulent boundary-layer equations with a two-layer eddy viscosity model are integrated numerically over a porous flat plate for a steady outer flow and a sinusoidally distributed injection-suction that varies harmonically with time. The dependence of the unsteady wall shear on the frequency and strength of injection-suction is investigated. The present results indicate that the time-averaged skin friction is always larger than the skin friction observed over a nonporous flat plate. Comparison with previous theoretical results indicates that the time-averaged skin friction is always smaller than the skin friction observed over a porous flat plate with steady, simultaneous injection-suction of the same strength. The extension of eddy viscosity models, developed for steady flows, to unsteady flows is discussed. | |
| publisher | The American Society of Mechanical Engineers (ASME) | |
| title | Turbulent Boundary Layers With Unsteady Injection-Suction | |
| type | Journal Paper | |
| journal volume | 102 | |
| journal issue | 3 | |
| journal title | Journal of Fluids Engineering | |
| identifier doi | 10.1115/1.3240695 | |
| journal fristpage | 364 | |
| journal lastpage | 371 | |
| identifier eissn | 1528-901X | |
| keywords | Suction | |
| keywords | Boundary layer turbulence | |
| keywords | Skin friction (Fluid dynamics) | |
| keywords | Flat plates | |
| keywords | Flow (Dynamics) | |
| keywords | Eddies (Fluid dynamics) | |
| keywords | Viscosity | |
| keywords | Turbulence | |
| keywords | Shear (Mechanics) | |
| keywords | Boundary layers | |
| keywords | Unsteady flow AND Equations | |
| tree | Journal of Fluids Engineering:;1980:;volume( 102 ):;issue: 003 | |
| contenttype | Fulltext |