[CIG-LONG] Re:Re: Re: Cumulative strain history in Gale et alia - Stokes, example (Walter Landry)

[Christoph Schrank]

Hi, Walter,

I wanted to simulate the classical simple Physics experiment with a 
solid ball falling in a fluid in a pipe where the frictional force is 
given by:

F_r = 6phrv,

lifting force by: F_l = -r_fluid V_ball g,

and Fg=r_ball V_ball g. Adding these up to zero for constant sinking 
velocity leads to: v_sink =(2/9)(r_ball - r_fluid )r^2 g/h.

I approximated the ball as a high-viscosity fluid but literally no 
deformation occured. Since there should be no free-slip conditions at 
the surface of the ball in Gale, I would have suggested to obtain a 
lower sinking velocity. If one applies the correction (for the 
analytical solution) regarding the width of the pipe (with no-slip bc's) 
the analytical velocity decreases more. Gale reaches an approximately 
constant velocity for the long-pipe input file I attached, so I thought 
this might applicable. I hope the sub- and superscripts show up properly 
in the above equations.

Cheers

Christoph

-- 
______________________
Christoph Schrank

University of Toronto
Department of Geology
Earth Sciences Centre

22 Russell Street
Toronto, ON, M5S 3B1
Canada

phon:

Lab:     416 946 7365
Office: 416 978 0833 

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