Multiscale turbulence (original) (raw)
Multiscale turbulence is a class of turbulent flows in which the chaotic motion of the fluid is forced at different length and/or time scales. This is usually achieved by immersing in a moving fluid a body with a multiscale, often fractal-like, arrangement of length scales. This arrangement of scales can be either passive or active Multiscale turbulence has also played an important role into probing the internal structure of turbulence. This sort of turbulence allowed researchers to unveil a novel dissipation law in which the parameter in
| Property | Value |
|---|---|
| dbo:abstract | Multiscale turbulence is a class of turbulent flows in which the chaotic motion of the fluid is forced at different length and/or time scales. This is usually achieved by immersing in a moving fluid a body with a multiscale, often fractal-like, arrangement of length scales. This arrangement of scales can be either passive or active As turbulent flows contain eddies with a wide range of scales, exciting the turbulence at particular scales (or range of scales) allows one to fine-tune the properties of that flow. Multiscale turbulent flows have been successfully applied in different fields., such as: * Reducing acoustic noise from wings by modifying the geometry of spoilers; * Enhancing heat transfer from impinging jets passing through grids; * Reducing the vortex shedding intensity of flows past normal plates without changing the shedding frequency; * Enhancing mixing by energy-efficient stirring; * Improving flow metering and flow conditioning in pipes; * Improving combustion. Multiscale turbulence has also played an important role into probing the internal structure of turbulence. This sort of turbulence allowed researchers to unveil a novel dissipation law in which the parameter in is not constant, as required by the Richardson-Kolmogorov energy cascade. This new law can be expressed as , with , where and are Reynolds numbers based, respectively, on initial/global conditions (such as free-stream velocity and the object's length scale) and local conditions (such as the rms velocity and integral length scale). This new dissipation law characterises non-equilibrium turbulence apparently universally in various flows (not just multiscale turbulence) and results from non-equilibrium unsteady energy cascade. This imbalance implies that new mean flow scalings exist for free shear turbulent flows, as already observed in axisymmetric wakes (en) |
| dbo:thumbnail | wiki-commons:Special:FilePath/Fractalgrids.svg?width=300 |
| dbo:wikiPageID | 45507060 (xsd:integer) |
| dbo:wikiPageLength | 9157 (xsd:nonNegativeInteger) |
| dbo:wikiPageRevisionID | 1122135295 (xsd:integer) |
| dbo:wikiPageWikiLink | dbr:Scientific_law dbr:Energy_cascade dbr:Reynolds_number dbr:Frequency dbr:Andrey_Kolmogorov dbc:Chaos_theory dbc:Turbulence dbr:Lewis_Fry_Richardson dbr:Turbulence dbr:Dissipation dbr:Heat_transfer dbr:Vortex_shedding dbr:Fluid dbr:Fractal dbr:Length_scale dbr:Automatic_control dbr:Root_mean_square dbc:Fluid_dynamics dbr:Eddy_(fluid_dynamics) dbr:Spoiler_(aeronautics) dbr:Freestream dbr:Acoustic_noise dbr:File:Fractalgrids.svg |
| dbp:id | FaWCLl_qVR4 (en) |
| dbp:title | See (en) |
| dbp:wikiPageUsesTemplate | dbt:Orphan dbt:Reflist dbt:YouTube |
| dct:subject | dbc:Chaos_theory dbc:Turbulence dbc:Fluid_dynamics |
| rdfs:comment | Multiscale turbulence is a class of turbulent flows in which the chaotic motion of the fluid is forced at different length and/or time scales. This is usually achieved by immersing in a moving fluid a body with a multiscale, often fractal-like, arrangement of length scales. This arrangement of scales can be either passive or active Multiscale turbulence has also played an important role into probing the internal structure of turbulence. This sort of turbulence allowed researchers to unveil a novel dissipation law in which the parameter in (en) |
| rdfs:label | Multiscale turbulence (en) |
| owl:sameAs | freebase:Multiscale turbulence wikidata:Multiscale turbulence https://global.dbpedia.org/id/2AefB |
| prov:wasDerivedFrom | wikipedia-en:Multiscale_turbulence?oldid=1122135295&ns=0 |
| foaf:depiction | wiki-commons:Special:FilePath/Fractalgrids.svg |
| foaf:isPrimaryTopicOf | wikipedia-en:Multiscale_turbulence |
| is dbo:wikiPageWikiLink of | dbr:Lewis_Fry_Richardson |
| is foaf:primaryTopic of | wikipedia-en:Multiscale_turbulence |
