Wind Drum Two Webs
Multi-web wind drum component
Description
Usage
Equations
Variables
Connections
Parameters
Summary Variables
The Wind Drum Two Webs component models simultaneous winding of two webs with variable roll radius and inertia.
The Wind Drum component must be at the end of two web lines.
Using the provided 1D rotational flange (flangec), the Wind Drum component can be equipped with a motor.
Consider the drum shown below:
Ta1,Ta2
Upstream tension
va1,va2
Upstream speed
τ
Motor torque (zero if modeling an idler roller)
ω
Angular velocity (positive means wind)
Rc
Core radius
R1⁡t,R2⁡t
Instantaneous roll radii for web 1 and 2
dB
Bearing damping coefficient
th1,th2
Web thicknesses
W1,W2
Web widths
Ta1⁢R1⁡t+Ta2⁢R2⁡t=τm−J⁡t⁢dωdt−dB⁢ω
va1=R1⁢ωva2=R2⁢ω
The roll inertia consists of the core inertia, Jc, and the approximate roll variable inertia, J⁡t:
J⁡t=Jc+π2⁢λ^⁢R⁡t4−Rc4
where
λ^=ρ1⁢W1⁢th1+ρ2⁢W2⁢th2th1+th2
Roll Radius
The time-varying roll radius is given by the following differential equations:
When Use stepwise=false, the effective roll radius is given by
dR⁡tdt=ω⁢th1+th22⁢π
with the following initial value:
R⁡0=12⁢Dinit+th1+th2
The radii of the layers are calculated as:
R1⁡t=R⁡t−th22
R2⁡t=R⁡t+th12
When Use stepwise=true and Use multistep=false the effective roll radius is given by:
dR⁡tdt={ω⁢th1+th2δφ0<φ<δφ0otherwise
where φ is the rotation of the drum between 0 and 2⁢π and the roll radius increases only over a portion of each turn defined by the merge angle δφ.
We also have the following initial value:
The radii of the layers are now calculated as:
When Use stepwise=true and Use multistep=true the effective layer radii are given by:
dR1tdt={ω⁢th1δφ10<φ^11<δφ10otherwise+{ω⁢th2δφ20<φ^12<δφ20otherwise
dR2tdt={ω⁢th1δφ10<φ^21<δφ10otherwise+{ω⁢th2δφ20<φ^22<δφ20otherwise
with the following intitial values:
R1⁡0=R⁡t+th12
R2⁡0=R⁡t+th22
In the above, δφ1 and δφ2 are the merge angles for layer 1 and 2, respectively.
Also, φ^ij are angles dependent on the initial web starting point angle parameters (φ2 and φ2→1) and the variable angle between the tangent point of web 1 and web 2, β12:
In this case, we also define R⁡t=12⁢R1⁡t+R2⁡t
Example: Using the multistep option
Consider this simple model which only covers the winding of two webs:
Relevant model parameters and layout is shown below:
The multistep winding results in the following sequence of changes to the radii:
Name
Value
Units
Modelica ID
FF1
RBF00
RBF01
RBF03
ARc
ATc
PRa
PR_a
RBFa
RBF_a
RB1
RB2
RB3
PRv
PR_v
Φ
Phi
RBFeccθ0
RBF_ecc_theta0
RBFecc
RBF_ecc
PTecc
PT_ecc
mweb
m_web
tanPointa
tanPoint_a
ATa
AWM1
frameVis
rollVis
rollVisColor
drumVis
RBFF1
RBFF2
R1
FAM2
TT1
ptR
pt_R
ptRmax
pt_Rmax
ptD
pt_D
ptT
pt_T
ptRotMatc
pt_RotMatc
ptey
pt_ey
ptez
pt_ez
reactioncorrection
reaction_correction
CADtorque
CAD_torque
BPT
w
rads
FAM1
FA1
TA1
framea1
Left web 3D connection point
frame_a1
framea2
frame_a2
framec
Roller holder base frame
frame_c
framed
External mass/inertia
frame_d
weba1
Web #1 entrance transfer information port
web_a1
weba2
Web #2 entrance transfer information port
web_a2
flangec
Drum rotation flange
flange_c
Rmax
Real output; drum and web radius m [1]
eccin
Real input; eccentricity signal m
ecc_in
reset
Boolean input to trigger roll radius reset
[1] Available if Enable radius sensor=true.
Web Properties
Default
Web Properties for layer 1
WP1
Name of the Web Properties record for layer 1 (buttom)
wp1
Web Properties for layer 2
WP2
Name of the Web Properties record for layer 2 (top)
wp2
Comp. Factor
1
Ratio of the thickness of the mixed web to the sum of thicknesses of component webs
CompressionFactor
Settings
Use alternative configuration
false
Choose between two possible solutions for the web/roll configuration
useAltConfig
Flip direction
Use this option when building web lines that go from right to left. See documentation for more information
flipDirection
Use fixed base
When checked (true), frame is fixed in the inertial coordinate frame
useFixedBase
r
0,0
m
Location of frame_b with respect to ground [1]
InitPos
θ
0
deg
Rotation about z axis [1]
InitAng
Enable radius sensor
When checked (true), drum outer radius is provided via an output signal
useSensor
[1] Available when Use fixed base=true.
Drum
Dinit
0.1
Initial outer roll diameter
D_init
D
0.10
Core diameter
Di
Core inner diameter
L
1.2
Drum length
Use cylindrical geometry
true
When checked (true), drum core inertia is calculated assuming a uniform cylindrical geometry
useCylindricalGeometry
ρ
2.7·103
kgm3
Drum core density [1]
rho_roll
kg
Drum core mass (excluding the holder frame) [2]
J
0.004
kg⁢m2
Drum core rotational inertia [2]
d
N⁢m⁢srad
Bearing viscous damping constant
Use CAD
When checked (true), mass and inertia are defined from an externally attached CAD component or a rigid body component
useCAD
Use reset
The roller diameter is reset to D_init with an external signal
useReset
[1] Enabled when Use cylindrical geometry=true
[2] Enabled when Use cylindrical geometry=false
Winding
Use stepwise
When checked (true), the roll diameter is changed over a portion of each rotation (instead of changing continuously)
useStepwise
Use multi-step
When checked (true), the roll diameter is changed over multiple steps
useMultistep
φ0
Angle offset of start of the combined web w.r.t local x-axis; φ0<360 [1]
phi0
δφ
Angle offset of start of web 2 (top layer) w.r.t initial tangent point; δφ<360 [1]
delta_phi
φ2
Angle offset of start of web 2 (top layer) w.r.t. initial tangent point; φ2+φ2→1<360−β12 [2]
phi12
φ2→1
Angle offset of start of web 1 (bottom layer) w.r.t. web 2 (top layer); φ2+φ2→1<360−β12 [2]
δφ1
Merge angle web 1 (bottom layer); δφ1<360 [2]
delta_phi1
δφ2
Merge angle web 2 (top layer); δφ2<360 [2]
delta_phi2
[1] Available when Use stepwise=true and Use multistep=false.
[2] Available when Use stepwise=true and Use multistep=true.
Eccentricity
Add eccentricity
When checked (true), a parameter is enabled for the roller eccentricity
addEccentricity
Use input
When checked (true), eccentricity is given by an input signal in meters
useInputEccentricity
e
Roller eccentricity
ecc
θ0
rad
Initial eccentricity angle
theta_ecc0
Frame
mf
Frame mass
m_frame
Jf
⋅1e−1
Frame inertia
J_frame
Add frame offset
When checked (true), frame connection point is placed at an offset w.r.t. the roll center
addFrameOffset
rf
0,⋅5⁢D
Offset in the XY plane [1]
rf [1] Enabled if Add frame offset is true.
Visualization
Show drum visualization
When checked (true), a visualization is produced for the drum
showVisualization_drum
Transparent drum
When checked (true), the drum visualization is transparent [1]
transparent_drum
Drum color
Blue
Color of the drum [1]
color_drum
Band color
Yellow
Color of a radial band on the drum [1]
color_band
Band angle
20
Band angle [1]
band_angle
Show frame
When checked (true), a visualization of the frame is created [4]
showVisualization_frame
Transparent frame
When checked (true) the frame visualization is transparent [4] and [5]
transparent_frame
Frame color
Orange
Color of the frame; [4] and [5]
color_frame
Show reaction force arrow
When checked (true), ground reaction force is visualized with an arrow
showReactionForce
Force arrow scale
1000
Force scale (N to m) [2]
forceScale
Force arrow color
Cyan
Force arrow color [2]
forceColor
Force arrow transparency
Force arrow transparency [2]
forceTransparent
Show reaction torque arrow
showReactionTorque
Torque arrow scale
100
Torque scale (N to m) [3]
torqueScale
Torque arrow color
Magenta
Torque arrow color [3]
torqueColor
Torque arrow transparency
Torque arrow transparency [3]
torqueTransparent
[1] Enabled if Show drum visualization is true.
[2] Enabled if Show reaction force arrow is true.
[3] Enabled if Show reaction torque arrow is true.
[4] Enabled if Add frame offset is true.
[5] Enabled if Show frame is true
summary_Radius
Roll radius
summary_Layers
Number of layers radius
See Also
Sources and Sinks
Web Handling Library
Download Help Document