Page 108 - Bird R.B. Transport phenomena
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§3.6  Use of the Equations of Change to Solve  Flow Problems  93

                                                I  '  I  '  /  '  Г         Fig. 3.6-5.  Flow-regime  dia-
                                                                            gram  for  the flow between  two
                                                                            coaxial  cylinders. The straight
                                12,000
                                                                            line labeled  "Rayleigh"  is Lord
                                       Turbulent flow  /                    Rayleigh's  analytic solution  for
                                10,000              /                       an  inviscid  fluid.  [See D. Coles,
                                                                            /. Fluid. Mech., 21,385-425
                                                                            (1965).]
                                8,000
                            9.
                            сГ
                                6,000                          Rayleigh  -


                                4,000  Transition  /  Doubly  '  Singly  Ь
                                               /   periodic  I periodic/l^
                                2,000



                                  -8000  -6000  -4000  -2000    2000  4000





                          specific  fluid.  This  diagram  demonstrates  how  complicated  this  apparently  simple  sys-
                                                                  4 5
                          tem  is. Further details may be found  elsewhere. '
                              The  preceding  discussion  should  serve  as  a  stern  warning  that intuitive  postulates
                          may be misleading.  Most  of us would  not think about postulating  the singly and  doubly
                          periodic  solutions  just  described.  Nonetheless,  this  information  is  contained  in  the
                          Navier-Stokes  equations. However,  since problems  involving  instability  and  transitions
                          between  several  flow  regimes  are extremely  complex, we  are forced  to use a combination
                          of  theory  and  experiment  to describe  them. Theory  alone  cannot yet  give us  all  the an-
                          swers, and carefully  controlled experiments will be needed  for  years  to come.

      EXAMPLE   3.6-4     A liquid  of constant density  and viscosity is in a cylindrical  container of radius R as shown  in
                          Fig. 3.6-6. The container is  caused  to rotate about  its  own  axis at an angular  velocity  П. The
     Shape of  the Surface  cylinder  axis is vertical, so that g  = 0, g  = 0, and g  = —g, in which g  is the magnitude  of the
                                                                   z
                                                    r
                                                          0
     of a Rotating  Liquid  gravitational  acceleration.  Find the shape  of  the free  surface  of  the liquid  when  steady  state
                          has been  established.


                              4
                               The initial work  on this subject  was  done by John William  Strutt (Lord Rayleigh)  (1842-1919),
                          who established  the field  of acoustics with his Theory of Sound, written on a houseboat on the Nile River.
                          Some original references  on Taylor instability  are: J. W. Strutt (Lord Rayleigh), Proc. Roy. Soc,  A93,
                          148-154  (1916); G. I. Taylor, Phil. Trans., A223, 289-343  (1923) and Proc. Roy. Soc. A157,  546-564  (1936);
                          P.  Schultz-Grunow and H. Hein, Zeits.  Flugwiss., 4, 28-30  (1956); D. Coles, /. Fluid. Mech. 21, 385-425
                          (1965). See also  R. P. Feynman, R. B. Leighton, and M. Sands, The Feynman  Lectures  in Physics,  Addison-
                          Wesley, Reading, MA  (1964), §41-6.
                              0
                               Other references on Taylor instability, as well  as instability  in other flow  systems, are: L. D. Landau
                          and  E. M. Lifshitz, Fluid Mechanics,  Pergamon, Oxford, 2nd edition (1987), pp. 99-106;  S. Chandrasekhar,
                          Hydrodynamic  and Hydromagnetic  Stability,  Oxford  University Press  (1961), pp. 272-342; H. Schlichting
                          and  K. Gersten, Boundary-Layer Theory, 8th edition (2000), Chapter 15; P. G. Drazin and W. H. Reid,
                          Hydrodynamic  Stability, Cambridge University Press  (1981); M. Van  Dyke, An  Album of Fluid Motion,
                          Parabolic Press, Stanford  (1982).
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