E.V.Semenenko Determination of limiting weighting of polydispersive particles of different density in pressure drege-carrying flow |
Applied hydromechanics, Vol. 9 (81) ¹ 4, (2007) |
| A new estimation parameter of fluid flow weighing ability is offered and its dependence on parameters of current and properties of transported material is analyzed basing the Chens equation for movement of a single particle in which Base, Magnus, Safman and Archimed forces are taken into consideration as well as forces of the inertial nature, the forces connected to presence of attached weights, forces of aerodynamic resistance and gravity. Assuming that vertical pulsation of fluid flow in a cylindrical pipe is described by periodic sinusoidal dependence, and the difference of average speeds of conveyance fluid and solid particles is proportional the hydraulic size of particles, equation determining the vertical speed of a solid particle is worked out. The analysis of this dependence reveals, that vertical speed of a particle in a pressure turbulent flow is composed of two components. Hence, the sign and value of the first component determine increase or decrease of average speed. It is proved, that the particle suspended by a flow, moves upwards under influence of turbulent pulsations if the size of the first component is positive, and precipitates on a bottom of the flow when this size is less than zero. |
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| TEXT LANGUAGE: Russian |