On the impulsively started rotating sphere
1967 ◽
Vol 27
(4)
◽
pp. 779-788
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Keyword(s):
The velocity field generated in a fluid of viscosity, v, by impulsively starting at time t = 0, a sphere of radius a spinning with angular velocity Ω about a diameter is described using a new expansion variable 2 √vt/r. It is first shown how the standard time-dependent boundary-layer equations can be modified to give series solutions satisfying all the boundary conditions. Next, that these new solutions are relevant when the Reynolds number R = a2Ω/v goes to infinity in such a way that $R^{\frac{1}{3}} \Omega t$ is large. Lastly, solutions are given, applicable at small times for non-zero Reynolds numbers. These last expansions show that the velocity components decay algebraically rather than exponentially at large distances.
Keyword(s):
Keyword(s):
1998 ◽
Vol 358
◽
pp. 357-378
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1985 ◽
Vol 160
◽
pp. 281-295
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1959 ◽
Vol 63
(588)
◽
pp. 722-722
1984 ◽
Vol 391
(1800)
◽
pp. 1-26
◽
Keyword(s):
1956 ◽
Vol 60
(541)
◽
pp. 67-70
Keyword(s):
Keyword(s):