SVD Status
Immanuel Gfall (HEPHY Vienna)
DESY Workshop
12 Apil 2012
SVD Status
SVD Design Status
•
•
•
•
Carbon fiber sandwich ribs
Layer 4,5,6 designed in Vienna
Ribs Layer 6
Layer 3 design still open
CFRP Sheet
Connector block
Airex
using JAE connector
Support Cones
Reinforcements
Conncectors
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
Hybrid Board
2
SVD Status
Endring Design
•
•
•
•
Separable ring
Integrated cooling channel
Endrings support the ladders
Endrings have an interface to the support cones
CO2 Inlet
Cooling Grooves
CO2 Outlet
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
3
SVD Status
Manufacturing
•
•
•
•
Grooves are cut into the halve pieces
Connection Tubes
Diffusion welded
Ultra sonic leak tested
Tubes brazed to the ring
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
4
SVD Status
Design Changes Summary
• Due to geometric constraints the SVD has been
modified in several aspects
1. Change of Layer 5 and 6 radius
2. Repositioning of Layer 4,5 and 6 in z-direction
3. Introduction of the ladder mounting mechanism
(SLM)
4. Layer 3: considerations regarding design and
location
5. Change in SVD support cone in respect to the
layer 3 changes
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
5
SVD Status
Fixed Layout (Option 4)
• Layout requires fewer ladders which leads to a
significant cost reduction
• After many tweaks all interferences are resolved
• Layers had to be shifted in z direction to cope with
geometric constraints
• Acceptance is completely covered
Layer
Radius [mm]
Ladder #
Windmill °
Overlap %
6
135
16
7
15.2
5
105
12
6
7.2
4
80
10
6
21.6
3
38
7
6
11.1
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
6
SVD Status
Configuration
• New configuration does not implement layer
3 into the SVD
• Reason: no suitable configuration possible
with given constraints
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
7
SVD Status
SVD Ladder Positions
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
8
SVD Status
Layer 3
• Layer 3 has severe interference issues with layer 4
(hybrid boards/ connectors)
• Even worse interferences with the support cones
• Support cones cannot be slimmer at the PXD side
• Currently there is no concept on how to fix the layer 3 to
the support cone while maintaining accessibility of the
layer 3 connectors
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
9
SVD Status
Problem
• Layer 4 barely scratches the acceptance region
• Thus layer 4 can not be moved in z-direction
• This restrains the position of layer 3 (also barely in the
acceptance region)
• Connectors interfere with layer 4 and the support cones
• Support cones cannot have a smaller diameter at layer 3
position
• Hybrid boards can not be made shorter, connectors can
not be moved to another position and putting both
connectors on top is also not possible
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
10
SVD Status
Solutions
• Mounting the SVD layer 3 onto the PXD
− Solution is not well accepted but not completely dropped
− Persisting space constraints and service paths make this
the solution less favorable
• A different approach in the sensor/readout design is
required to create new design possibilities
• New idea: introduce the origami scheme also in layer 3
+ With this solution the readout would be in the backward
region
+ This provides space for a fixture in the forward region
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
11
SVD Status
Performance of the Origami Scheme
• Simulation by Manfred Valentan shows a small degradation of the
impact parameter when using the origami scheme
• Difference projected impact parameter: 0.3 %
• Difference z impact parameter: 0.6%
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
12
SVD Status
Support Cones
• Support cones got shorter for the PXD mounting solution
• Diameter around layer 4 can be increased to provide more space for
services and shielding masks
• The previous version of the support cones can be used for the
origami scheme in layer 3
• Maybe another mounting solution is more preferable
• That needs to be investigated
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
13
SVD Status
Anchor Points
• Dimensions in z direction are fixed
• Increase or decrease of those numbers makes it
impossible to build the detector unless radii change
again
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
14
SVD Status
Layer 3 Envelope
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
15
SVD Status
Endring SLM + Cooling
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
16
SVD Status
New Layout for L4,5,6
•
•
•
•
New design fulfills all requirements
Assembly is possible from above
CTE compensation through sliding mechanism
Cooling contact might be critical
SLM
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
17
SVD Status
SLM Prototyping
• A model of the mechanism was constructed by Yoshiyuki
Onuki using 3D printing technology
• This prototypes show the principle mechanism and
provides the first impression that the mechanism works
as expected
• Next step: production of a metal mockup to investigate
tolerances and CTE contraction
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
18
SVD Status
Cooling Boundary Conditions
• Power dissipation/APV: 0.4 W
• 1 Origami sensor features 10 APVs
Origamis
/Ladder
Ladders
APVs
Origami
APVs
Hybrid
Power/
Layer
[W]
Power
Origami
[W]
Layer 6
3
16
480
320
320
192
Layer 5
2
14
240
240
192
96
Layer 4
1
10
100
200
120
40
Layer 3
0
7
0
140
56
0
47
820
900
688
328
Sum
• 360 W dissipated at the hybrid boards
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
19
SVD Status
Cooling Requirements
• Smallest possible material budget in the acceptance
region
• Temperature on top of APV25 @ -20°C for SNR
improvement
• Cooling system needs to handle 1kW+ of dissipated
heat (including PXD)
• Dry Air Volume (max 5% rel. humidity)
• SVD outside temperature: ~23°C
• Different cooling contact for hybrid boards and
Ladders
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
20
SVD Status
Heater
•
•
•
•
•
•
•
SVD volume temperature -10°C
CDC-SVD interface temperature 23°C
Thermal insulation is required
Active heating could be required
This usually adds material (e.g. copper)
Could result in unwanted effects
Better solution should be used!
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
21
SVD Status
CFRP Heater Solution
•
•
•
•
Uses conductive properties of CF
UD Fibers + 1 additional basket weave layer
Resistance: ~15 Ohm/m
Average temperatures of 47 °C in the center area at
4.5 A are possible
“Plane of
• dT = 1 °C
Hope”
Electrical
Connection
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
22
SVD Status
Discussion Items
•
•
•
•
•
Layer 3 options
SLM feasibility
Endring production
Mockup
Cooling
12 Apil 2012
Immanuel Gfall (HEPHY Vienna)
23