Fr.: tube d'écoulement
Same as → stream tube.
Fr.: aptitude à s'écouler, coulabilité
The ability of a body of matter (liquid, gas, loose particulate solid) to flow.
Tacandegi, from tacandé (originally tacandag), agent noun of tacidan, → flow, + noun suffix -i.
An observation which expands previous observations and aims at obtaining complementary data in particular with other telescopes/instruments.
Follow-up, from follow, from O.E. folgian, fylgan "to follow, pursue," from W.Gmc. *fulg- (cf. O.Fris. folgia, M.Du. volghen, Ger. folgen "to follow") + up, O.E. up, uppe (cf. Du. op, Ger. auf "up, upward"), from PIE base *upo "up from below;" cf. O.Pers./Av. upā; Skt. úpa; Gk. hypo; L. sub, → hypo-; → observation.
Nepâheš, → observation; peygir, from pey "after; step," related to pâ "foot, step, track," → foot, + gir present stem of gereftan "to take, seize" (Mid.Pers. griftan, Av./O.Pers. grab- "to take, seize," cf. Skt. grah-, grabh- "to seize, take," graha "seizing, holding, perceiving," M.L.G. grabben "to grab," from P.Gmc. *grab, E. grab "to take or grasp suddenly;" PIE base *ghrebh- "to seize").
Fr.: tache de queue
Agent noun of follow, from O.E. folgian, fylgan "to follow, pursue," from W.Gmc. *fulg- (cf. O.Fris. folgia, M.Du. volghen, Ger. folgen "to follow").
Laké, → spot; peyrow "follower," from pey "step; after," related to pâ "foot, step, track," → foot, + row "going; which goes," present stem of raftan "to go, walk, proceed," Mid.Pers. raftan, raw-, Proto-Iranian *rab/f- "to go; to attack."
Fr.: écoulement forcé
A fluid flow generated when external forces cause the fluid to flow, for example when a flow is caused by a pump. It contrasts with → free flow.
Fr.: écoulement libre
A fluid flow which develops when density differences within the fluid are the only driving forces. See also → forced flow.
Fr.: flot galactique
ostacân bâ marpel-e kahkešâni
Fr.: flot à l'échelle galactique
The enormous amounts of → mass and → energy released from active galaxies into the → intergalactic medium. → Supermassive black holes, believed to exist at the centres of active galaxies (→ active galaxy), → accrete matter and liberate huge quantities of energy. The energy output is often observed as → active galactic nuclei (AGN) outflows in a wide variety of forms, e.g. → collimated → relativistic jets and/or huge overpressured cocoons in → radio, → blueshifted broad → absorption lines in the → ultraviolet and → optical, → warm absorbers and ultrafast outflows in → X-rays, and → molecular gas in → far infrared. Moreover, the processes of → star formation and → supernova explosions release mass/energy into the surroundings. This → stellar feedback heats up, ionizes and drives gas outward, often generating large-scale outflows/→ winds. Galactic outflows are observed at low redshifts reaching a velocity as large as 1000 km s-1 and at high-z up to z ~ 5, sometimes extending over distances of 60-130 kpc. Galactic-scale outflows may be a primary driver of galaxy evolution through the removal of cool gas from star-forming regions to a galaxy's → halo or beyond.
Fr.: écoulement géostrophique
Oceanography: A flow resulting from → geostrophic balance. In geostrophic flow water moves along the lines of constant pressure or → isobars. Geostrophic flow is characterized by small → Rossby and → Ekman numbers.
1) foruz, foruq, foruzeš; 2) foruzidan
Fr.: 1) rougoiement, incandescence, éclat; 2) rougeoyer, s'embraser, être incandescent, luire rouge
1a) A light emitted by or as if by a substance heated to luminosity; incandescence.
1b) Brightness of color.
M.E. glowen, from O.E. glowan "to shine as if red-hot," ultimately from PIE *ghlo-.
Foruz-, foruzidan, afruxtan "to light, kindle;" related to foruq "light, brightness" (Mid.Pers. payrog "light, brightness"); rôšan "light; bright, luminous;" ruz "day;" Mid.Pers. rošn light; bright," rôc "day;" O.Pers. raucah-; Av. raocana- "bright, shining, radiant," raocah- "light, luminous; daylight;" cf. Skt. rocaná- "bright, shining, roka- "brightness, light;" Gk. leukos "white, clear;" L. lux "light," also lumen "light, window," luna "Moon;" E. light; Ger. Licht; Fr. lumière; PIE base *leuk- "light, brightness."
hot accretion flow
tacân-e farbâl-e dâq
Fr.: écoulement d'accrétion chaud
A type of → accretion flow by a → compact object such as a → black hole which has a high → virial temperature, is → optically thick, and occurs at lower mass → accretion rates compared with → cold accretion flows. In a hot accretion flow with a very low mass accretion rate, the electron mean free path is very large, and so the accreting → plasma is nearly collisionless. In this type of accretion flow, thermal conduction transports the energy from the inner to the outer regions. As the gas temperature in the outer regions can be increased above the → virial temperature , the gas in the outer regions can escape from the gravitational potential of the central black hole and form outflows, significantly decreasing the mass accretion rate.
Fr.: flot de Hubble
Fr.: flot de Hubble-Lemaître
tacân-e nâtanjidani, ~ tanješnâpazir
Fr.: écoulement incompressible
A flow whose volume or density does not change under pressure, and therefore its density is a constant. In other words, an ideal flow in which the → divergence of velocity is zero. → compressible flow.
Fr.: afflux, débit entrant
1) The act or process of flowing in or into. Something that flows
in or into. Opposite of → outflow.
Fr.: flot d'information
The flow of data into a system or to the end users.
Fr.: écoulement isentrope
A unit of energy equivalent to one kilowatt (1 kW) of power expended for one hour (1 h) of time. The kilowatt-hour is not a standard unit in any formal system, but it is commonly used to measure the consumption of electrical energy. To convert to → joules, use: 1 kWh = 3.6 × 106 J = 3.6 × 1013→ ergs.
Fr.: écoulement laminaire
A flow in which the particles of fluid are moving orderly, and in which adjacent layers or laminas glide smoothly over another with little mixing between them. A laminar flow may rapidly transform into a → turbulent flow for large → Reynolds numbers.
large Reynolds number flow
tacân bâ adad-e bozorg-e Reynolds
Fr.: écoulement à grand nombre de Reynolds
A turbulent flow in which viscous forces are negligible compared to nonlinear advection terms, which characterize the variation of fluid quantities. The dynamics becomes generally turbulent when the Reynolds number is high enough. However, the critical Reynolds number for that is not universal, and depends in particular on boundary conditions.