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See detailCapillary and Gravity-driven Instabilities in Finite Circular Containers
Dauby, Pierre ULg; Narayanan, Ranga; Johnson, D. et al

in Bulletin of the American Physical Society, Vol. 43, n°9 (1998, November)

When a horizontal fluid layer is heated from below, convection sets in provided the vertical temperature gradient exceeds a critical value. The motion is due to a combined effect of gravity and ... [more ▼]

When a horizontal fluid layer is heated from below, convection sets in provided the vertical temperature gradient exceeds a critical value. The motion is due to a combined effect of gravity and capillarity when the upper surface of the fluid is free. Convection usually takes the form of a regular pattern of convective cells, which are often hexagonal or roll-like in horizontally infinite layers. In confined geometries, the appearance of the instability phenomenon is greatly influenced by the presence of lateral walls which inhibit convection due to friction and which also determine the shape of the convective cells. In this work we present a theoretical and experimental analysis of the thermo-convective instability of a fluid layer contained in a circular container. The motion and the temperature perturbations in the air layer above the fluid are also taken into account. The convective threshold is determined as a function of the aspect ratio of the vessel and the convective stationary and oscillatory structures appearing in the non linear regime are also studied. Experimental results are presented and compared with the theoretical approach. [less ▲]

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Peer Reviewed
See detailMeasurement of the power output during the acceleration phase of all-put arm cranking exercise
Vanderthommen, Marc ULg; Francaux, Marc; Johnson, D. et al

in International Journal of Sports Medicine (1997), 18

Detailed reference viewed: 5 (0 ULg)