Threedimensional nature of the flow past a fixed transverse cylinder
Abstract
The flow past a fixed circular cylinder at Reynolds numbers of about 40,000, which is of a random threedimensional nature, is analyzed on the basis of measurements of relevant velocities, pressure, and forces. It is shown that at Reynolds numbers of about 40,000, vortex shedding around a fixed cylinder has not the stability which characterizes it at low Reynolds number. This is marked by the onset of a slow variation of pressure at the cylinder base and by similar variations in the amplitude of fluctuations at the Strouhal frequency and at the second harmonic. These lowfrequency modulations, being nonuniform along the cylinder, are associated with a lack of longitudinal correlation.
 Publication:

NASA STI/Recon Technical Report A
 Pub Date:
 November 1976
 Bibcode:
 1976STIA...7728946S
 Keywords:

 Aerodynamic Forces;
 Boundary Layer Flow;
 Circular Cylinders;
 Flow Velocity;
 Pressure Distribution;
 Three Dimensional Flow;
 Correlation;
 Cylindrical Bodies;
 Frequency Modulation;
 NavierStokes Equation;
 Reynolds Number;
 Velocity Distribution;
 Vortex Streets;
 Fluid Mechanics and Heat Transfer