Aerodynamics, lift

Another problem, prevalent ia areas where severe icing conditions are met, is referred to as galloping of power lines. When ice forms on a power line, there is frequently a prevailing wiad which causes the ice to take a teardrop or airfoil shape. This foil provides an aerodynamic lift to the conductors and under certain conditions the conductors can go iato a resonant vibration such that large standing waves are created that exert enormous forces on the system. Miles of power lines and the towers along them have been destroyed by this phenomenon. 

The draft is due to the difference between the density of the air leaving the tower and that entering the tower, and to the aerodynamic lift of the wind passing over the top of the tower. 

In a general hydrodynamic system, the vorticity w is perpendicular to the velocity field v, creating a so-called Magnus pressure force. This force is directed along the axis of a right-hand screw as it would advance if the velocity vector rotated around the axis toward the vorticity vector. The conditions surrounding a wing that produce aerodynamic lift describe this effect precisely (see Fig. 2). 

Colloidal particles are large enough that any given particle, not in the center of the tube, will experience a pressure difference across its diameter due to the higher velocity on one side than on the other. Thus, the particle will experience a "lift-force" tending to move it away from the wall toward the center of the channel. This "lift-force" is not unlike the aerodynamic lift on an airfoil due to the "Bernoulli effect". 

A more favourable skip orientation would be with the skips oriented in the North-South direction. This orientation places the Coriolis force at right angles to the near-wall lateral aerodynamic lift force. For the 1700 m depth scenario with 15 m/s air velocity, a change in skip orientation to North-South results in a reduction of required shaft diameter of approximately... 

Small particles in a shear field as shown in Fig. 15 experience a lift force perpendicular to the direction of flow. The shear lift origmates from the inertia effects in the viscous flow around the particle and is fundamentally different from aerodynamic lift force. The expression for the inertia shear lift was first obtained by... 

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