TERMIUM Plus®
The Government of Canada’s terminology and linguistic data bank.
UNSTABLE FLOW [5 records]
Record 1 - internal organization data 2021-01-27
Record 1, English
Record 1, Subject field(s)
- Anti-pollution Measures
- Water Pollution
Record 1, Main entry term, English
- droplet breakaway
1, record 1, English, droplet%20breakaway
correct
Record 1, Abbreviations, English
Record 1, Synonyms, English
Record 1, Textual support, English
Record number: 1, Textual support number: 1 DEF
A... boom failure resulting from excessive current velocity [in which] the head wave formed upstream of the oil mass contained within a boom becomes unstable and oil droplets are torn off and become entrained in the water flow beneath the boom. 2, record 1, English, - droplet%20breakaway
Record 1, Key term(s)
- droplet break away
Record 1, French
Record 1, Domaine(s)
- Mesures antipollution
- Pollution de l'eau
Record 1, Main entry term, French
- arrachement de gouttelettes
1, record 1, French, arrachement%20de%20gouttelettes
correct, masculine noun
Record 1, Abbreviations, French
Record 1, Synonyms, French
- entraînement de gouttelettes 2, record 1, French, entra%C3%AEnement%20de%20gouttelettes
masculine noun
Record 1, Textual support, French
Record number: 1, Textual support number: 1 CONT
Les courants violents peuvent engendrer un deuxième type d'échappement, l'arrachement ou l'entraînement de gouttelettes. Dans ce cas, un bourrelet se constitue à la marge distale de la nappe retenue par la barrière; le courant déstabilise le bourrelet duquel il arrache et entraîne des gouttelettes. Si ces dernières ne sont pas suffisamment légères pour remonter sous la nappe, elles s'échappent sous la barrière. 2, record 1, French, - arrachement%20de%20gouttelettes
Record 1, Spanish
Record 1, Textual support, Spanish
Record 2 - internal organization data 2007-07-16
Record 2, English
Record 2, Subject field(s)
- Geomorphology and Geomorphogeny
- Meteorology
Record 2, Main entry term, English
- mountain barrier
1, record 2, English, mountain%20barrier
correct
Record 2, Abbreviations, English
Record 2, Synonyms, English
Record 2, Textual support, English
Record number: 2, Textual support number: 1 CONT
A flow approaching a mountain barrier will most likely go over the barrier rather than around it if the barrier is long, if the cross-barrier wind component is strong, and if the flow is unstable, near-neutral, or only weakly stable. These conditions are frequently met in the United States because the long, north-south oriented mountain ranges lie perpendicular to the prevailing westerly winds and the jet stream. Mountain barriers orientated perpendicular to the flow cause the highest accelerations across the barrier and frequently generate lee waves downwind of the obstacle as well as downslope windstorms. 1, record 2, English, - mountain%20barrier
Record 2, French
Record 2, Domaine(s)
- Géomorphologie et géomorphogénie
- Météorologie
Record 2, Main entry term, French
- barrière montagneuse
1, record 2, French, barri%C3%A8re%20montagneuse
correct, feminine noun
Record 2, Abbreviations, French
Record 2, Synonyms, French
- barrière de montagnes 2, record 2, French, barri%C3%A8re%20de%20montagnes
correct, feminine noun
Record 2, Textual support, French
Record number: 2, Textual support number: 1 CONT
Une masse d'air qui rencontre une barrière montagneuse va la contourner par-dessus. 3, record 2, French, - barri%C3%A8re%20montagneuse
Record number: 2, Textual support number: 2 CONT
[Visitez] la Montagne du Caldeirão, une barrière montagneuse qui [arrête] les vents forts, conférant au Algarve son climat particulier. 4, record 2, French, - barri%C3%A8re%20montagneuse
Record number: 2, Textual support number: 3 CONT
Le climat au «Camp de Tarragona» est méditerranéen, grâce à l'influence de la mer et la protection du semi-cercle montagneux. Cette barrière de montagnes protège [la plaine] de certains facteurs climatologiques externes, comme les brouillards de la vallée de l'Ebre et les influences du climat continental provenant du centre de l'Espagne. 2, record 2, French, - barri%C3%A8re%20montagneuse
Record 2, Spanish
Record 2, Textual support, Spanish
Record 3 - internal organization data 1999-03-16
Record 3, English
Record 3, Subject field(s)
- Atmospheric Physics
- Atmospheric, Climatic and Meteorological Phenomena
Record 3, Main entry term, English
- billow cloud
1, record 3, English, billow%20cloud
correct
Record 3, Abbreviations, English
Record 3, Synonyms, English
Record 3, Textual support, English
Record number: 3, Textual support number: 1 DEF
A cloud or series of clouds that forms when sufficient moisture exists in the billow for condensation to occur. 2, record 3, English, - billow%20cloud
Record number: 3, Textual support number: 1 CONT
Billow clouds are created when different layers of wind flow at different velocities resulting in unstable turbulence between the layers. The common name for this instability is Kelvin-Helmholtz instability. Billow clouds are created in the upward branch of each of the "eddies" if the air within this branch has a high enough relative humidity that, upon lifting, the air parcel reaches saturation. Individual billow clouds generally last a few minutes. Billow clouds provide a visible signal to pilots of potentially dangerous turbulence. 3, record 3, English, - billow%20cloud
Record 3, French
Record 3, Domaine(s)
- Physique de l'atmosphère
- Phénomènes météorologiques, climatiques et atmosphériques
Record 3, Main entry term, French
- nuage en rouleaux
1, record 3, French, nuage%20en%20rouleaux
correct, masculine noun
Record 3, Abbreviations, French
Record 3, Synonyms, French
- nuage en lames 2, record 3, French, nuage%20en%20lames
correct, masculine noun
- nuage en bancs 3, record 3, French, nuage%20en%20bancs
masculine noun
Record 3, Textual support, French
Record number: 3, Textual support number: 1 DEF
Nuage ou série de nuages se formant quand l'air est suffisamment humide pour que la condensation se produise dans les rouleaux. 4, record 3, French, - nuage%20en%20rouleaux
Record number: 3, Textual support number: 1 OBS
Pour plusieurs auteurs, il y aurait synonymie entre les nuages en bancs, en lames ou en rouleaux et la variété «undulatus». Il reste préférable de les distinguer (ce qui n'est pas toujours facile). D'autres nuages (nuages andains et nuages d'onde) appartiennent aussi à la variété «undulatus». 5, record 3, French, - nuage%20en%20rouleaux
Record 3, Spanish
Record 3, Campo(s) temático(s)
- Física de la atmósfera
- Fenómenos meteorológicos, climáticos y atmosféricos
Record 3, Main entry term, Spanish
- nube en rodillo
1, record 3, Spanish, nube%20en%20rodillo
feminine noun
Record 3, Abbreviations, Spanish
Record 3, Synonyms, Spanish
Record 3, Textual support, Spanish
Record number: 3, Textual support number: 1 DEF
Nube o serie de nubes que se forman cuando el aire está suficientemente húmedo para que se produzca condensación en los rodillos. 2, record 3, Spanish, - nube%20en%20rodillo
Record 4 - internal organization data 1999-02-26
Record 4, English
Record 4, Subject field(s)
- Cooling and Ventilating Systems
Record 4, Main entry term, English
- backward inclined fan
1, record 4, English, backward%20inclined%20fan
correct
Record 4, Abbreviations, English
Record 4, Synonyms, English
- backward inclined blade fan 2, record 4, English, backward%20inclined%20blade%20fan
correct, see observation
- BI fan 1, record 4, English, BI%20fan
- backward curved centrifugal fan 3, record 4, English, backward%20curved%20centrifugal%20fan
correct
- backward inclined centrifugal fan 4, record 4, English, backward%20inclined%20centrifugal%20fan
correct
- backwardly inclined centrifugal fan 1, record 4, English, backwardly%20inclined%20centrifugal%20fan
correct
- backwardly curved blade centrifugal fan 5, record 4, English, backwardly%20curved%20blade%20centrifugal%20fan
correct
- backward-blade fan 6, record 4, English, backward%2Dblade%20fan
Record 4, Textual support, English
Record number: 4, Textual support number: 1 CONT
Centrifugal fans are divided into four general classifications: Forward Curve (FC), Backward Inclined (BI), Radial Blade, and Tubular Centrifugal. 1, record 4, English, - backward%20inclined%20fan
Record number: 4, Textual support number: 2 CONT
Backward curved and backward inclined blade fans. Backward curved and backward inclined blades are slightly less efficient, cost less, and generate slightly more noise than the airfoil type. The number of blades is usually ten to sixteen and the fan scroll is the same as for airfoil fans. Backward curved blades... are constant thickness airfoil blades and are preferred over straight backward inclined blades... because they allow smoother air flow and are stronger. Backward curved blade fans will operate over the full range of air flow from wide open to shut off, whereas backward inclined blade fans are unstable under flow condition below the design point. These fans are used in industrial applications in which fouling of the blades by airborne contaminants would minimize the efficiency advantage of airfoil blade fans. 2, record 4, English, - backward%20inclined%20fan
Record number: 4, Textual support number: 1 OBS
"Backward curved blade fan" and "backward inclined blade fan" are usually synonyms, but some sources make a distinction between those two terms. In the "backward curved blade fan", the blade is curved, and in the "backward inclined blade fan", the blade is straight. 7, record 4, English, - backward%20inclined%20fan
Record 4, French
Record 4, Domaine(s)
- Systèmes de refroidissement et de ventilation
Record 4, Main entry term, French
- ventilateur à réaction
1, record 4, French, ventilateur%20%C3%A0%20r%C3%A9action
correct, masculine noun
Record 4, Abbreviations, French
Record 4, Synonyms, French
- ventilateur à pales courbées vers l'arrière 2, record 4, French, ventilateur%20%C3%A0%20pales%20courb%C3%A9es%20vers%20l%27arri%C3%A8re
masculine noun
- ventilateur à pales inclinées vers l'arrière 2, record 4, French, ventilateur%20%C3%A0%20pales%20inclin%C3%A9es%20vers%20l%27arri%C3%A8re
masculine noun
- ventilateur centrifuge à réaction 1, record 4, French, ventilateur%20centrifuge%20%C3%A0%20r%C3%A9action
correct, masculine noun
- ventilateur centrifuge à aubes à réaction 1, record 4, French, ventilateur%20centrifuge%20%C3%A0%20aubes%20%C3%A0%20r%C3%A9action
correct, masculine noun
- ventilateur centrifuge à pales couchées en arrière 1, record 4, French, ventilateur%20centrifuge%20%C3%A0%20pales%20couch%C3%A9es%20en%20arri%C3%A8re
correct, masculine noun
- ventilateur centrifuge de réaction 3, record 4, French, ventilateur%20centrifuge%20de%20r%C3%A9action
masculine noun
- ventilateur centrifuge à aubes inclinées vers l'arrière 4, record 4, French, ventilateur%20centrifuge%20%C3%A0%20aubes%20inclin%C3%A9es%20vers%20l%27arri%C3%A8re
correct, masculine noun
Record 4, Textual support, French
Record number: 4, Textual support number: 1 CONT
Ventilateurs à pales courbées et inclinées vers l'arrière. Les pales courbées et inclinées vers l'arrière sont un peu moins efficaces, coûtent moins cher et sont légèrement plus bruyantes que les pales à profil aérodynamique. Il y a habituellement dix à seize pales montées sur la roue et le carter spiralé est identique à celui d'un ventilateur à pales à profil aérodynamique. Les pales courbées vers l'arrière [...] constituent des pales à profil aérodynamique d'épaisseur constante et sont plus utilisées que les pales droites inclinées vers l'arrière [...] parce qu'elles génèrent un débit plus uniforme et sont plus durables. Les ventilateurs à pales courbées vers l'arrière fonctionnent sur toute la gamme de débits d'air, de la position complètement ouverte à la position complètement fermée, tandis que le fonctionnement des ventilateurs à pales inclinées vers l'arrière devient instable lorsque le débit est inférieur à la valeur du point de calcul. Lorsque ces ventilateurs à pales à profil aérodynamique sont utilisés dans l'industrie, l'encrassement des pales entraîné par des particules contaminées en suspension dans l'air réduit le rendement de ce type de ventilateurs. 2, record 4, French, - ventilateur%20%C3%A0%20r%C3%A9action
Record number: 4, Textual support number: 1 OBS
Source de "ventilateur centrifuge à aubes inclinées vers l'arrière" : Giblin et Missenard, Cours supérieur de chauffage, ventilation et conditionnement d'air, Eyrolles, 1968, vol. 1, p. 69. 4, record 4, French, - ventilateur%20%C3%A0%20r%C3%A9action
Record 4, Spanish
Record 4, Textual support, Spanish
Record 5 - internal organization data 1986-11-25
Record 5, English
Record 5, Subject field(s)
- Aerodynamics and Theory of Gases
- Aeronautical Engineering and Maintenance
Record 5, Main entry term, English
- three-dimensional unstable viscous-flow phenomena
1, record 5, English, three%2Ddimensional%20unstable%20viscous%2Dflow%20phenomena
correct
Record 5, Abbreviations, English
Record 5, Synonyms, English
Record 5, Textual support, English
Record number: 5, Textual support number: 1 CONT
Other developments using essentially laser-based technology make it possible to measure simultaneous three-dimensional unstable viscous-flow phenomena and then to display images of the flow around a test article. 1, record 5, English, - three%2Ddimensional%20unstable%20viscous%2Dflow%20phenomena
Record 5, French
Record 5, Domaine(s)
- Théorie des gaz et aérodynamique
- Aérotechnique et maintenance
Record 5, Main entry term, French
- mesure tridimensionnelle d'écoulement visqueux instationnaire
1, record 5, French, mesure%20tridimensionnelle%20d%27%C3%A9coulement%20visqueux%20instationnaire
feminine noun
Record 5, Abbreviations, French
Record 5, Synonyms, French
Record 5, Textual support, French
Record number: 5, Textual support number: 1 CONT
(...) de nouvelles techniques exploitant essentiellement les propriétés des lasers sont mises au point pour permettre des mesures tridimensionnelles simultanées d'écoulements visqueux instationnaires et de les visualiser. 1, record 5, French, - mesure%20tridimensionnelle%20d%27%C3%A9coulement%20visqueux%20instationnaire
Record 5, Spanish
Record 5, Textual support, Spanish
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