|
aZ
|
|
centrifugal acceleration
|
|
bN
|
|
width of the profile slot
|
|
bS
|
|
width of the profile web
|
|
cF
|
|
proportionality factor
|
|
d
|
|
flake thickness
|
|
D
|
|
roller diameter
|
|
E
|
|
energy
|
|
EM
|
= E/M
|
energy absorption, mass related
|
|
EV
|
= E/V
|
energy absorption, volume related
|
|
f
|
|
portion of fines below a certain particle size of x
|
|
F
|
|
grinding force
|
|
Fsp
|
= D/L
|
specific grinding force
|
|
g
|
|
gravity acceleration
|
|
h
|
|
distance between rollers at a = a0
|
|
hS
|
|
height of the profile web
|
|
k
|
= g/a
|
standardised back strain
|
|
kF
|
|
spring constant
|
|
l
|
|
axial coordinate
|
|
L
|
|
roller length
|
|
M
|
|
mass of the mill feed
|
|
Mt
|
= M/t
|
material throughput
|
|
n
|
|
1) number of revolutions or 2) modulation parameter
|
|
p
|
|
pressure
|
|
pc
|
|
characteristic pressure
|
|
peff
|
|
effective pressure
|
|
pm
|
|
maximum pressure
|
|
P
|
|
power
|
|
q
|
= a/a0
|
standardised angle coordinate
|
|
Q
|
|
mass portion, mass summation distribution
|
|
s
|
|
gap width
|
|
seff
|
|
effective gap width
|
|
t
|
|
time
|
|
tP
|
|
pitch of the profile
|
|
T
|
|
torque
|
|
Tsp
|
= T/D2L
|
specific torque
|
|
u
|
|
circumferential speed
|
|
uc
|
= (gD/2)0,5
|
characteristic circumferential speed
|
|
v
|
|
particle speed
|
|
v0
|
|
particle speed at a = a0
|
|
WM
|
= EM/f
|
specific grinding work
|
|
x
|
|
particle size
|
|
xm
|
|
medium particle size
|
|
z
|
|
relative speed
|
|
|
|
|
|
a
|
|
rotation angle
|
|
a0
|
|
compression angle
|
|
b
|
|
force attack angle
|
|
bF
|
|
force attack angle fixed roller
|
|
bL
|
|
force attack angle loose roller
|
|
g
|
|
back strain angle
|
|
d
|
|
solid volume portion
|
|
dM
|
|
solid volume portion, medium value of dSch and dR
|
|
dR
|
|
solid volume portion of bulk material, shaked
|
|
dS
|
|
solid volume portion at the narrowest gap
|
|
dSch
|
|
solid volume portion of bulk material, poured
|
|
d0
|
|
solid volume portion at a = a0
|
|
e
|
= (d-s)/d
|
relative back strain
|
|
q
|
|
standardised compression
|
|
qm
|
|
maximum standardised compression
|
|
k
|
|
throughput elasticity
|
|
l
|
|
standardised axial coordinate
|
|
n
|
= Mt/rDLu
|
specific throughput
|
|
n0
|
|
throughput number
|
|
r
|
|
solid density
|
|
rR
|
|
solid density of bulk material, shaked
|
|
rSch
|
|
solid density of bulk material, poured
|
|
s
|
= s/D
|
relative gap width
|
|
jx
|
|
outer friction angle
|
|
je
|
|
effective friction angle
|
|
jP
|
|
grade of profile filling
|
