In the present study, a decompression experiment involving two rotating concentric cylinders with hydraulic oil between clearances was performed. The dependency of occurrence condition gaseous cavitation in investigated not only based on rotation speed, which corresponds to shear strength flow, but also pressure history flow. As result, characteristics were found be divided into regions separat...

A numerical study has been carried out for slot air jet impingement cooling of horizontal concentric circular cylinders. The slot air jet is situated at the symmetry line of a horizontal cylinder along the gravity vector and impinges on the bottom of the outer cylinder which is designated as θ=0°. The outer cylinder is partially opened at the top with a width of W=30mm and is kept at constant t...

ABSTRACT In a gap between two concentric cylinders, we discover that the small heavy particle settling velocity (Vs) is greater than its associated terminal (Vt) in featureless turbulence generated by counter-rotating inner and outer cylinders simultaneously. The peak enhancement of Vs occurs at St × (Vt/u′) ∼ 1, where u′ are, respectively, r.m.s. fluctuation Stokes number defined as ratio resp...

We have conducted a numerical studv of spherical Couette Vlow -the flow between differentiallv rotatin~ concentric spheres. When the qa D ratio o{(R2-RI)/RI (where R 1 and R 2 are the radii of the inner and outer spheres) is small, the flow near the e~uator resembles that between cylinders, the classic Tavlor-Couette ~roblem. As in Tavlor-Couette flow, when the angular momentum gradient, measur...

Three-tori solutions of the Navier-Stokes equations and their dynamics are elucidated by use of a global Poincare map. The flow is contained in a finite annular gap between two concentric cylinders, driven by the steady rotation and axial harmonic oscillations of the inner cylinder. The three-tori solutions undergo global bifurcations, including a new gluing bifurcation, associated with homocli...