Download User Manual Version 1.1 - Computational Infrastructure for

For vector field, spectrum for the poloidal and toroidal components are written by
l=m Z
i
1 X h
m 2
−m 2
(B Sl ) + B Sl
dV,
BSsq (m) =
V l=0
l=m Z
i
1 X h
m 2
−m 2
BT sq (m) =
(B T l ) + B T l
dV.
V l=0
[vol pwr prefix] lm.dat Volume average of mean square amplitude of the fields
as a function of spherical harmonic order n = l − m. The wave number in the
latitude direction is referred in this spectrum data. For scalar field, the spectrum is
l=l−n Z h
i
1 X
l−n 2
−l+n 2
fl
+ fl
dV.
fsq (n) =
V l=n
For vector field, spectrum for the poloidal and toroidal components are written by
l=l−n Z h
2
2 i
1 X
BSsq (n) =
B Sll−n + B Sl−l+n
dV,
V l=n
l=l−n Z h
i
2
1 X
−l+n 2
dV.
+
B
B Tl−n
BT sq (n) =
Tl
l
V l=n
10.5.3
layered spectrum data
Spectrum data for the each radial position are written by defining volume pwr spectr prefix
in control file. By defining layered pwr spectr prefix, following spectrum data
averaged over the fluid shell is written. Data format is the same as the volume spectrum
data, but radial grid point and radius of the layer is added in the list. The following files
are generated.
[layer pwr prefix] l.dat Surface average of mean square amplitude of the fields
as a function of spherical harmonic degree l and radial grid id k. For scalar field, the
spectrum is
m=l Z
1 X
(flm )2 dS.
fsq (k, l) =
S m=−l
46