Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-24T18:51:52.235Z Has data issue: false hasContentIssue false

An experimental and computational study of the post-collisional flow induced by an impulsively rotated sphere

Published online by Cambridge University Press:  25 October 2019

Sophie A. W. Calabretto*
Affiliation:
Department of Mathematics and Statistics, Macquarie University, Sydney 2109, Australia
James P. Denier
Affiliation:
Department of Mathematics and Statistics, Macquarie University, Sydney 2109, Australia
Benjamin Levy*
Affiliation:
6 Lorne Street, Auckland 1010, New Zealand
*
Email addresses for correspondence: [email protected], [email protected]
Email addresses for correspondence: [email protected], [email protected]

Abstract

The unsteady flow due to a sphere, immersed in a quiescent fluid, and suddenly rotated, is a paradigm for the development of unsteady boundary layers and their collision. Such a collision arises when the boundary layers on the surface of the sphere are advected towards the equator, where they collide, serving to generate a radial jet. We present the first particle image velocimetry measurements of this collision process, the resulting starting vortex and development of the radial jet. Coupled with new computations, we demonstrate that the post-collision steady flow detaches smoothly from the sphere’s surface, in qualitative agreement with the analysis of Stewartson (Grenzschichtforschung/Boundary Layer Research (ed. H. Görtler), Springer, 1958, pp. 60–70), with no evidence of a recirculation zone, contrary to the conjectured structure of Smith & Duck (Q. J. Mech. Appl. Maths, vol. 20, 1977, pp. 143–156).

Type
JFM Papers
Copyright
© 2019 Cambridge University Press 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Formerly affiliated with Department of Engineering Science, University of Auckland, New Zealand.

References

Alciatore, D.2018 Pool and Billiards balls: physical characteristics of pool balls. Available at: https://billiards.colostate.edu/faq/ball/smooth/.Google Scholar
Banks, W. H. H. 1965 The boundary layer on a rotating sphere. Q. J. Mech. Appl. Maths 18, 443454.Google Scholar
Banks, W. H. H. 1976 The laminar boundary layer on a rotating sphere. Acta Mech. 24, 273287.Google Scholar
Banks, W. H. H. & Zaturska, M. B. 1979 The collision of unsteady laminar boundary layers. J. Engng Maths 13, 193212.Google Scholar
Batchelor, G. K. 1967 An Introduction to Fluid Dynamics. Cambridge University Press.Google Scholar
Blackburn, H. M. & Sherwin, S. J. 2004 Formulation of a Galerkin spectral element-Fourier method for three-dimensional incompressible flows in cylindrical geometries. J. Comput. Phys. 197, 759778.Google Scholar
Boirin, O., Deplano, V. & Pelissier, R. 2006 Experimental and numerical studies on the starting effect on the secondary flow in a bend. J. Fluid Mech. 574, 109129.Google Scholar
Bowden, F. P. & Harbour, P. J. 1966 The aerodynamic resistance to a sphere rotating at high Mach numbers in the rarefied transition regime. Proc. R. Soc. Lond. A 293, 156168.Google Scholar
Bowden, F. P. & Lord, R. G. 1963 The aerodynamic resistance to a sphere rotating at high speed. Proc. R. Soc. Lond. A 271, 143153.Google Scholar
Calabretto, S. A. W. & Denier, J. P. 2019 Instabilities in the flow around an impulsively rotated sphere. Phys. Rev. Fluids 4, 073904.Google Scholar
Calabretto, S. A. W., Levy, B., Denier, J. P. & Mattner, T. W. 2015a The unsteady flow due to an impulsively rotated sphere. Proc. R. Soc. Lond. A 471, 20150299.Google Scholar
Calabretto, S. A. W., Mattner, T. W. & Denier, J. P. 2015b The effect of seam imperfections on the unsteady flow within a fluid-fllled torus. J. Fluid Mech. 767, 240253.Google Scholar
Cowley, S. J., van Dommelen, L. L. & Lam, S. T. 1990 On the use of Lagrangian variables in descriptions of unsteady boundary-layer separation. Phil. Trans. R. Soc. Lond. A 333, 343378.Google Scholar
Dennis, S. C. R. & Duck, P. W. 1988 Unsteady flow due to an impulsively started rotating sphere. Comput. Fluids 16, 291310.Google Scholar
van Dommelen, L. L. 1990 On the Lagrangian description of unsteady boundary-layer separation. Part 2. The spinning sphere. J. Fluid Mech. 210, 627645.Google Scholar
Floryan, J. M. 1986 Görtler instability of boundary-layers over concave and convex walls. Phys. Fluids 29, 23802387.Google Scholar
Garret, S. J. & Peake, N. 2002 The stability and transition of the boundary layer on a rotating sphere. J. Fluid Mech. 456, 199218.Google Scholar
Hada, T. & Ito, A. 2003 Visualization of breakdown process of vortex flows formed around a rotating sphere. Trans. Vis. Soc. Japan 23, 231234.Google Scholar
Howarth, L. 1951 Note on the boundary layer on a rotating sphere. Phil. Mag. 42, 13081315.Google Scholar
Kluwick, A. & Wohlfahrt, H. 1986 Hot-wire-anemometer study of the entry flow in a curved duct. J. Fluid Mech. 165, 335353.Google Scholar
Kohama, Y. & Kobayashi, R. 1983 Boundary-layer transition and the behaviour of spiral vortices on rotating spheres. J. Fluid Mech. 137, 153164.Google Scholar
Kreith, F., Roberts, L. G., Sullivan, J. A. & Sinha, S. N. 1963 Convection heat transfer and flow phenomena of rotating spheres. Intl J. Heat Mass Transfer 6, 881895.Google Scholar
Lingwood, R. J. 1996 An experimental study of absolute instability of the rotating-disk boundary-layer flow. J. Fluid Mech. 314, 373405.Google Scholar
Riley, N. 1998 Unsteady fully-developed flow in a curved pipe. J. Engng Maths 34, 131141.Google Scholar
Simpson, C. J. & Stewartson, K. 1982 A note on a boundary-layer collision on a rotating sphere. Z. Angew. Math. Phys. 33, 370378.Google Scholar
Smith, F. T. & Duck, P. W. 1977 Separation of jets or thermal boundary layers from a wall. Q. J. Mech. Appl. Maths 20, 143156.Google Scholar
Stewartson, K. 1958 On rotating laminar boundary layers. In Grenzschichtforschung/Boundary Layer Research (ed. Görtler, H.), pp. 6070. Springer.Google Scholar
Stewartson, K., Cebeci, T. & Chang, K. C. 1980 A boundary-layer collision in a curved duct. Q. J. Mech. Appl. Maths 33, 5975.Google Scholar
Thomas, C. & Davies, C. 2018 On the impulse response and global instability development of the infinite rotating-disc boundary layer. J. Fluid Mech. 857, 239269.Google Scholar
Wadey, P. 1992 On the development of Görtler vortices in wall jet flow. J. Engng Maths 26, 297313.Google Scholar