-
[email protected]
Henrique de Oliveira Caiafa Duarte
LNLS, Campinas, Brazil
TWIICE SOLEIL Workshop
-
Outline
• Codes Overall Comparison
• Tapered Cavity
• Tapered Collimator
• UVX Longitudinal Kicker
• SIRIUS BPM
• SIRIUS Shadowing Masks
• Final Comments
January 16, 2014 TWIICE SOLEIL Workshop 2 of 28
-
Codes Overall Comparison (Wakefield Solvers)
Code CST (WAK) GdfidL (TD) ACE3P (T3P)
Method FIT(explicit) FDTD(explicit) FEM(implicit)
Mesh PBA mesh Prismatic-filling mesh
Tetrahedral Mesh (n-th order)
Model Drawing Interactive and analytical
Analytical only “Less-interactive” and analytical (Cubit)
Geom. Parameter Sweep
Yes No No
OS Win/Linux Linux only Solver: Linux only Graphical:
Win/Linux/MAC
User interface (Draw+Run+View Results)
Completely user-friendly
Only via Xterminal
Intermediate (Cubit + Paraview)
Year/Versions Tested 2012 2012-2013 2012-2013 January 16, 2014
TWIICE SOLEIL Workshop 3 of 28
-
Tapered Cavity – Stepsize Sweep
11.7 mm 12.7 mm
13.6 mm 11.2 mm
bunch length = 2.758 mm
40.0 mm
-0.01 0 0.01 0.02 0.03-0.04
-0.03
-0.02
-0.01
0
0.01
0.02
0.03GdfidL - Longitudinal Wakepotential
W, V
/pC
s, m
ECHO
step=150 m
step=100 m
step=50 m
-0.01 0 0.01 0.02 0.03-0.04
-0.03
-0.02
-0.01
0
0.01
0.02
0.03CST - Longitudinal Wakepotential
W, V
/pC
s, m
ECHO
step=150 m
step=100 m
step=50 m
-0.01 0 0.01 0.02 0.03-0.04
-0.03
-0.02
-0.01
0
0.01
0.02
0.03ACE3P - Longitudinal Wakepotential
W, V
/pC
s, m
ECHO
ACE3P
Very preliminar transition for Sirius BPMs;
Indirect testbeams Integration Method
Step = 80% of limit
January 16, 2014 TWIICE SOLEIL Workshop 4 of 28
-
Tapered Cavity – Stepsize Sweep
-0.01 0 0.01 0.02 0.03-2.5
-2
-1.5
-1
-0.5
0
0.5
1CST - Vertical Dipole Wakepotential
WD
y, V
/pC
/m
s, m
ECHO
step=50 m
step=100 m
step=150 m
-0.01 0 0.01 0.02 0.03-2.5
-2
-1.5
-1
-0.5
0
0.5
1GdfidL - Vertical Dipole Wakepotential
WD
y, V
/pC
/m
s, m
ECHO
step=50 m
step=100 m
step=150 m
bunch length = 2.758 mm; driving bunch offset = 3*STEPSIZE
11.7 mm 12.7 mm
13.6 mm 11.2 mm 40.0 mm
January 16, 2014 TWIICE SOLEIL Workshop 5 of 28
-
-0.01 0 0.01 0.02 0.03
-0.03
-0.02
-0.01
0
0.01
0.02
W, V
/pC
s, m
L=20
L=60
ECHO
L=40
Tap. Cav. – GdfidL Pipe Length Sweep
Lpipe
0 5 10 15 20 25 30 35 40-8
-6
-4
-2
0
2
4
6
8x 10
-3GdfidL - Longitudinal Wakepotential
W, V
/pC
s, m
L=20
L=60
ECHO
L=40
0 5 10 15 20 25 30-400
-300
-200
-100
0
100
200
300Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
L=20
L=60
ECHO
L=40
9.4 9.45 9.5
-300
-200
-100
0
100
200
Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
L=20
L=60
ECHO
L=40
160 MHz shift
600 MHz shift
20
MH
z shift
January 16, 2014 TWIICE SOLEIL Workshop 6 of 28
-
9.4 9.45 9.5
-300
-200
-100
0
100
200
Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
ECHO
L=60
L=40
L=20
0 5 10 15 20 25 30-400
-300
-200
-100
0
100
200
300Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
ECHO
L=60
L=40
L=20
0 5 10 15 20 25 30 35 40-8
-6
-4
-2
0
2
4
6
8x 10
-3 CST - Longitudinal Wakepotential
W, V
/pC
s, m
ECHO
L=60
L=40
L=20
Tap. Cav. – CST Pipe Length Sweep
Lpipe
140 MHz shift
570 MHz shift
10
MH
z shift
-0.01 0 0.01 0.02 0.03
-0.03
-0.02
-0.01
0
0.01
0.02
Longitudinal Wakepotential
W, V
/pC
s, m
ECHO
L=60
L=40
L=20
January 16, 2014 TWIICE SOLEIL Workshop 7 of 28
-
9.4 9.45 9.5
-300
-200
-100
0
100
200
Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
ECHO
L=80
L=20
0 5 10 15 20 25 30-400
-300
-200
-100
0
100
200
300Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
ECHO
L=80
L=20
0 5 10 15 20 25 30 35 40-8
-6
-4
-2
0
2
4
6
8x 10
-3 Longitudinal Wakepotential
W,
V/p
C
s, m
ECHO
L=80
L=40
L=20
-0.01 0 0.01 0.02 0.03
-0.03
-0.02
-0.01
0
0.01
0.02
Longitudinal Wakepotential
W,
V/p
C
s, m
ECHO
L=80
L=40
L=20
Tap. Cav. – ACE3P Pipe Length Sweep
140 MHz shift
550 MHz shift
Lpipe 8 M
Hz sh
ift
January 16, 2014 TWIICE SOLEIL Workshop 8 of 28
-
-0.01 0 0.01 0.02 0.03-0.25
-0.2
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
0.2CST - Longitudinal Wakepotential
W,
V/p
C
s, m
ECHO
step=150 m
step=100 m
step=50 m
11.2 mm
Tapered Collimator – Stepsize Sweep
11.7 mm 10.7 mm
13.6 mm
bunch length = 2.758 mm
40.0 mm
-0.01 0 0.01 0.02 0.03-0.05
-0.04
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
0.04
0.05CST - Longitudinal Wakepotential
W, V
/pC
s, m
ECHO
step=150 m
step=100 m
step=50 m
January 16, 2014 TWIICE SOLEIL Workshop 9 of 28
-0.01 0 0.01 0.02 0.03-0.05
-0.04
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
0.04
0.05GdfidL - Longitudinal Wakepotential
W,
V/p
C
s, m
ECHO
step=150 m
step=100 m
step=50 m
Indirect Interfaces Integration Method
-
Longitudinal Kicker (UVX SR)
Parameter value
(mm or rad)
G. 1 G. 2 G. 3
R2 84 82 84.7
R3 79 77 79.7
0.42 0.42 0.2
0.25 0.25 0.39
d 74 67 52.8
50.2 55 42
b 52.3 52.3 25
Three stages of the design (DAΦNE and PLS based) evolution:
Geometric parameters for the three kicker models considered for UVX
storage ring.
Parameter Value
Center Frequency (11/4 FRF) 1.31GHz
Bandwidth (1/2 FRF) 238MHz
Max. desired CBMI GR 10% of DR
Main design goals of the electromagnetic project
January 16, 2014 TWIICE SOLEIL Workshop 10 of 28
-
Long. Kicker Optimization
Longitudinal Impedance Optimization
The electric field pattern of TM01 mode calculated with CST
σ = 11mm
January 16, 2014 TWIICE SOLEIL Workshop 11 of 28
-
Long. Kicker Optimization
Ridged waveguide optimization (CST MW): reduction of the cutoff
frequency through S-2,1 parameters
Ridged waveguide geometry Ridged WG ports
January 16, 2014 TWIICE SOLEIL Workshop 12 of 28
-
Long. Kicker Characterization
Min(S1,1) tracking
encoder
sliding
platform
Step
motor
Disassembled (a) and assembled (b) pieces
Bead-pull method automated setup
January 16, 2014 TWIICE SOLEIL Workshop 13 of 28
-
Long. Kicker Characterization
Bead-pull method (6mm radius metallic bead):
Q = 4.49
Rshunt = 700 Ω
Qloaded = 4.15
Rshunt = 700.7 Ω
simulation measurements
January 16, 2014 TWIICE SOLEIL Workshop 14 of 28
-
Long. Kicker: CST vs. GdfidL
σ = 11mm
Geometry 1 – Real Part of Longitudinal Impedance
January 16, 2014 TWIICE SOLEIL Workshop 15 of 28
-
BPM (SIRIUS SR) Properties of dielectric materials for
simulations
a) The inner profile of the standard
BPM Button geometry.
b) Modified BPM Button with
dielectric material on top of it. All
units are in mm.
Considered Properties Value (AlN – BN)
Permittivity, εr 9 – 4
Thermal Conductivity, σt 160 – 46 W/K.m
Loss Tangent, tanδε, @1MHz 0.003 – 0.0034
January 16, 2014 TWIICE SOLEIL Workshop 16 of 28
-
BPM – Best 3 Candidates
Bell-Shaped BPM Button Step-Shaped BPM Button Flat BPM
Button
Based on a well known button geometry style
implemented at ALBA [5], just like the standard
button analyzed previously.
Derived from the previously analyzed
modified button, with reduced vacuum
insulator dimensions though to increase HOM’s frequencies.
Designed with the objective of increasing the button
cutoff frequency, without losing its sensitivity, since its
bottom face area was kept
the same as the other geometries.
January 16, 2014 TWIICE SOLEIL Workshop 17 of 28
-
BPM – 3 Candidates Performance
January 16, 2014 TWIICE SOLEIL Workshop 18 of 28
-
BPM – 3 Candidates Performance
Geometry
κloss-, mV/pC
Bell-Shaped Step-Shaped Flat
σS, mm 2.65–4.5–6.0 2.65–4.5–6.0 2.65–4.5–6.0
AlN 4.5–0.9–0.3 8.9–2.5–0.8 5.6–0.9–0.2
BN 3.6–0.8–0.4 8.3–2.3–0.7 4.6–0.7–0.2
Summary results of the loss factor for 2.65, 4.5, and 6 mm bunch
lengths, for the BPM Button geometries including the ceramics
materials, AlN and BN.
lossav
lossM
ITP
2
0Single-bunch power loss
goes from 1.9 to 4.4 W, for σS = 2.65 mm, at Iav = 500 mA in M =
864 bunches and 1.73 μs revolution period T0.
January 16, 2014 TWIICE SOLEIL Workshop 19 of 28
-
BPM – Updated Mechanical Project
Kovar Housing w/ gassing channels SS Feedthrough SMA adapter
Al2O3 gasket
Complete assembly
Mo Inner conductor (button + pin)
January 16, 2014 TWIICE SOLEIL Workshop 20 of 28
-
BPM – Updated Mechanical Project
Kovar Housing w/ gassing channels SS Feedthrough SMA adapter
Al2O3 gasket
Complete assembly
Mo Inner conductor (button + pin)
SS body
January 16, 2014 TWIICE SOLEIL Workshop 21 of 28
-
Shadowing Masks (SIRIUS SR)
2-Ridge, 10 mm width
1-Ridge, 10 mm width Axisymmetric
1-Ridge, 5 mm width
Other tested transverse
profiles w10 wfull
wpar, dh1 wpar, dh0.5
January 16, 2014 TWIICE SOLEIL Workshop 22 of 28
-
GdfidL vs ECHO
Axisymmetric; soft-hard; h = 2 mm
0 5 10 15 20 25 30 350
5
10
15Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
ECHO
GdfidL
0 5 10 15 20 25 30 350
2
4
6
8
Real Part of Longitudinal Impedance
Re(Z
||),
Frequency, GHz
ECHO
GdfidL
January 16, 2014 TWIICE SOLEIL Workshop 23 of 28
-
Shadowing Masks – Final Parameter Sweep
Edge points (sweep)
Shadow point
Resulting mask profile from sweep
The resulting isolines were chosen between broadband and
narrowband impedance isolines. Ilustrating this:
z (mm) 0 20 21 22
0.75
h (mm)
1.0 1.25 1.5 1.75 2.0 2.25
isoline 1
isoline 2
resulting in
hard steep step January 16, 2014 TWIICE SOLEIL Workshop 24 of
28
-
Shadowing Masks – Parameter Sweep Results
0 5 10 15 20 25 30 35
0
0.5
1
1.5
2
2.5
Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
steep, h=2
steep, h=1.75
steep, h=1.5
steep, h=1.25
steep, h=1
5 10 15 20 25 30 35
0
0.5
1
1.5
2
2.5
3
Real Part of Longitudinal Impedance
Re(Z
||),
Frequency, GHz
steep, h=2
steep, h=1.75
steep, h=1.5
steep, h=1.25
steep, h=1
5 10 15 20 25 30 35
0
0.5
1
1.5
2
2.5
3
Real Part of Longitudinal Impedance
Re(Z
||),
Frequency, GHz
hard, h=2.25
hard, h=2
hard, h=1.75
hard, h=1.5
hard, h=1.25
0 5 10 15 20 25 30 35
0
0.5
1
1.5
2
2.5
Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
hard, h=2.25
hard, h=2
hard, h=1.75
hard, h=1.5
hard, h=1.25
0 5 10 15 20 25 30 35
0
0.5
1
1.5
2
2.5
Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
step, h=1.75
step, h=1.5
step, h=1.25
step, h=1
step, h=0.75
5 10 15 20 25 30 35
0
0.5
1
1.5
2
2.5
3
Real Part of Longitudinal Impedance
Re(Z
||),
Frequency, GHz
step, h=1.75
step, h=1.5
step, h=1.25
step, h=1
step, h=0.75
- For Zbroad, there are common levels between types (for
example: hard,h2.25 = steep,h2 = step,h1.75) - The strongest HOMs
magnitudes depend only on iris height - Step-type is more
advantageous for Znarrow, since it requires lower height for the
same shadow
hard steep step
January 16, 2014 TWIICE SOLEIL Workshop 25 of 28
-
Shadowing Masks – Example of chosen isolines
Observation: low resolution on narrowband impedance
10 20 30 40 50 60 70 80 900
0.5
1
1.5
2
Real Part of Longitudinal Impedance
Re(Z
||),
Frequency, GHz
hard, h=2
steep, h=1.875
step, h=1.75
0 10 20 30 40 50 60 70 80 900
0.5
1
1.5Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
hard, h=2
steep, h=1.875
step, h=1.75
isoline 1
10 20 30 40 50 60 70 80 900
0.5
1
1.5
2
Real Part of Longitudinal Impedance
Re(Z
||),
Frequency, GHz
hard, h=1.5
steep, h=1.375
step, h=1.25
0 10 20 30 40 50 60 70 80 900
0.5
1
1.5Imaginary Part of Longitudinal Impedance
Im(Z
||),
Frequency, GHz
hard, h=1.5
steep, h=1.375
step, h=1.25
isoline 2
January 16, 2014 TWIICE SOLEIL Workshop 26 of 28
-
Final Comments
• A limited comparison was done among EM codes regarding
wakefield simulation – attention must be paid to the dispersion
errors and evanescent modes near PML;
• UVX Longitudinal Kicker is in operation;
• Bell-shaped BPM button is under brazing tests, national and
external companies are interested on the production;
• SR masks are being designed by Vacuum Group according to the
proposed isolines;
• Some other components are in the final stages of EM project:
dipole chambers, gate valves and flanges.
January 16, 2014 TWIICE SOLEIL Workshop 27 of 28
-
Acknowledgment
• Kwok Ko – ACE3P;
• A. Tadeu Gomes, B. Bastos, M. Galheigo – SINAPAD (Brazilian
Computing System);
• Igor Zagorodnov – ECHO;
• R. Nagaoka (SOLEIL), G. Rehm (DIAMOND), A. Olmos (ALBA), G.
Kube (DESY) and many other colleagues around the globe;
• S. Marques, L. Sanfelici, F. Rodrigues, O. Bagnato, R.
Defavari, R. Seraphim and T. Rocha – LNLS Team.
January 16, 2014 TWIICE SOLEIL Workshop 28 of 28
