METHOD FOR DETERMINING AERODYNAMIC DRAG COEFFICIENT OF A SOLID SPHERE WHEN GAS IS BLOWN FROM ITS SURFACE Russian patent published in 2023 - IPC G01N15/10 

FIELD: physics.

SUBSTANCE: invention relates to the development of methods and devices for laboratory studies of physical processes, in particular for studying the patterns of movement of solid or liquid particles in a two-phase flow. The method includes measuring the aerodynamic force acting on a hollow sphere with a porous shell blown by a uniform gas flow, when pressurized compressed gas is supplied to the inner cavity of the sphere. A hard hollow sphere with a porous shell is fixed on the long arm of the lever adapted for rotation around a horizontal axis located on a fixed support point. On the short arm of the lever, a rod is fixed, which is in contact with the receiving area of the force sensor. The moments of gravity applied to the lever arms are preliminarily balanced by placing an additional load on the short arm of the lever. Compressed gas under pressure is fed into the inner cavity of the sphere through a thin-walled tube. A uniform blowing gas flow is fed to the sphere from the bottom up. For each velocity value of the blowing gas flow, the force acting on the receiving area of the force sensor is measured in the absence of gas blowing from the surface of the sphere, and when blowing gas with a given value of the gas flow density is fed, the volumetric flow rate of the gas supplied to the cavity of the sphere and the speed of the blowing gas flow are measured. The dependence of the aerodynamic drag coefficient on the Reynolds number of the blowing flow and the density of the gas flow blown through the porous shell are determined from the given algebraic relations.

EFFECT: determining the coefficient of aerodynamic resistance of a solid sphere when blowing gas from its surface with high accuracy in a wider range of Reynolds numbers of the blowing flow.

1 cl, 3 dwg, 3 tbl