The "Cottbus Geophysical Facility 2a" (CoGeoF2a)
also/formally known as "large spherical gap"
Further Information
M. Sc. Michael Hoff
T +49 (0) 355 69 4626
F +49 (0) 355 69 4891
michael.hoff(at)b-tu.de
LG3D, Raum 13
| inner radius ri | 40 and 60 [mm] |
| outer radius ro | 120 [mm] |
| gap width d | 60 and 80 [mm] |
| radius ratio η | 0.5 |
| inner rotation rate Ωi | 200 [rpm] |
| outer rotation rate Ωo | 60 [rpm] |
| Libration of inner sphere | 60 ± 60 [rpm] |
Co-, differential and conter rotating system
Reynolds number
\[Re = {{r_i^2 \Omega} \over {\nu}}\]
Taylor number in co-rotating system
\[Ta = {{4d^4 \Omega^2} \over {\nu^2}}\]
Taylor number in differential rotating system
\[Ta = {{4d_o^4 \Omega^2} \over {\nu^2}}\]
Rossby number
\[Ro = {{\Omega_i - \Omega_o} \over {\Omega_o}}\]
Ekman number in differential rotating system
\[E = {{\nu} \over {d \Omega_o}}\]
Libration
\[\Omega_1 (t) = \Omega_0 + \epsilon \cdot cos(\omega t)\]