AERODYNAMICS OF CYLINDRICAL FINITE LENGTH BODIES

Abstract

Studies were carried out in the test section of a closed-type wind tunnel. This paper presents the results of velocity distribution in the wake behind short cylinders. To study the effect of the relative length of short cylinders on the aerodynamics of the flow in the wake behind the body, the profiles of the mean velocity were measured in various sections behind short cylinders in the median planes coinciding with the cylinder axis and perpendicular to the cylinder axis. The calculation of resistance of transversely and longitudinally streamlined short cylinders is also given. To determine aerodynamic drag, cylinders with spherical and flat ends were used, as was an ellipsoid of revolution for comparison. The drag coefficient of a transversely streamlined ellipsoid of revolution is somewhat less than its value for a short cylinder at the same elongation of the bodies. In a longitudinal flow around a short cylinder with spherical ends and ellipsoids of revolution, the drag coefficients smoothly decrease with an increase in the Reynolds number to some minimum values. Based on the results of aerodynamic studies, the regularities of the flow around finite length cylinders with different ends shapes in a free air flow with longitudinal and transverse flow in a wide range of geometric and operating parameters have been established.