1. HCAL preliminary analysis and results

2. Outline Introduction ECAL modules simplifications
Comparison of ECAL assembly on two HCAL designs :
Videau (SDHCAL)
Tesla roman (AHCAL)
Conclusions

3. Introduction : purpose
The purpose of this presentation is to study consequences of HCAL design on ECAL modules in a mechanical point of view
Static analysis are done under self weight.

4. ECAL modules simplifications

5. Numerical model for ECAL modules
Results obtained from ILD update (20/10/2016)
Marc ANDUZE (LLR)
Simplified model for ECAL
Simplifications
1000mm*
Description:
Shell model using ANSYS ACP
Orthotropic carbon plies
5 Columns of alveoli
15 rows of alveoli
* Space between rails was arbitrarily chosen equal to 1000mm but changing it can also be part of improvement studies

6. ECAL modules simplification
Note :
Static analysis under self weight
Module located at 12 o’clock (1 of the 8 possible orientations)
ECAL modules simplification
Results obtained from ILD update (20/10/2016) g
Simplifications
The corner is the closest region to the next ECAL module when assembled in the barrel.
Data:
Max displacement of 0.43mm in the middle of the structure
0.056mm obtained at corner
Data:
Max displacement of 0.43mm in the middle of the structure
0.057mm obtained at corner
Warning : behavior along z axis is a bit different.

7. Summary : Charts and tables
Model
Max displacement (mm)
Displacement at the corner (mm)
Nodes
Running time (s)
Error with regard to max displacement (%)
Error with regard to corner displacement(%)
Time improvement (%)
Shell
0.430
0.057
37 579
N/A
Solid 3D with flange
0.433
0.056
45 214
36.177
0.5
1.8
69.0
When having almost the same deformation at representative points, we can have a significant benefit in term of time consumption
However no analysis can be done regarding stresses
Behavior along the z axis not precisely reproduced

8. Comparison of ECAL assembly on HCAL

9. 2 design options for HCAL
Videau (SDHCAL)
(5 wheels to produce the HCAL barrel)
Provided by Jean-Christophe IANIGRO (IPNL)
Tesla (AHCAL)
(2 wheels to produce the HCAL barrel)
Provided by Karsten Gadow (DESY)

10. 1st step: ECAL integration
Ecal dimensions * :
A = mm
Provided to ensure 2.5mm gap between ECAL modules
B = 940.0mm
Constrained by total barrel length
C = 187.3mm
Constrained by total stack up of 15 layers C A B
*Dimensions provided depend on the initial shell thickness therefore they might be slightly different than reality

11. 1st step: ECAL integration
On Videau design
On Tesla Design

12. 1st step: ECAL integration zoom
From ILD TDR V4:
(p189)
HCAL internal radius = 2058mm
1st step: ECAL integration zoom
On Videau design
Internal HCAL radius* = 2 069mm
On Tesla Design
Internal HCAL radius* = 1 956mm
2.5mm gap has been defined between ECAL module for assembly with provided information between ECAL and HCAL we can see that ECAL assembly within Tesla version is not possible because HCAL internal radius is not consistent with ILD TDR.
*Dimensions provided depend on shell thickness (i.e. absorber thickness) therefore they might be slightly different than reality

13. 1st step: ECAL integration zoom
On Videau design
Internal HCAL radius* = 2 069mm
On Tesla Design
Internal HCAL radius* = 1 956mm !
2.5mm gap has been defined between ECAL module for assembly with provided information between ECAL and HCAL we can see that ECAL assembly within Tesla version is not possible because HCAL internal radius is not consistent with ILD TDR. We must change ECAL dimension

14. 1st step: ECAL integration zoom
On Videau design
On Tesla Design
A = mm A
2.5mm gap has been defined between ECAL module for assembly with provided information between ECAL and HCAL we can see that ECAL assembly within Tesla version is not possible. However in order to run first calculations we reduced the ECAL length (i.e. A = mm for Tesla Model) !

15. 2nd step: absorber definition
For Videau
For Tesla
Absorber were given with a thickness of 15mm of stainless steel
Absorber were given with a thickness of 16mm
Absorber thickness are not the same.
They are directly linked to the structure stiffness

16. 3rd step: Cassette mass definition
For Videau
For Tesla
Cassette mass definition was given to be about 4.6t per HCAL module.
This gives approximately 48.8kg/m²
Cassette mass definition was given to be 17kg/m² for 19mm absorber and 1mm of stainless steel within cassette
For 16mm absorber there should be 4mm stainless steel within cassettes
Adding 3mm of stainless steel (density 7850kg/m^3) gives an estimate of 41kg/m² for 16mm absorber
Mass involved for calculations are different

17. 4th step: support definition
For Videau
For Tesla
No support mechanism
Dissymmetric support
Fixed at 9 o’clock
Able to slide on a horizontal plane at 3 o’clock
Support mechanism provided
Symmetrical support at 9 and 3 o’clock

18. 5th step: barrel definition
From ILD TDR V4:
(p189)
HCAL
z length = 4700mm !
X 2
X 5
Barrel length is not consistent between the two design. The difference represents 350mm +/- shell thickness which are not taken into account in shell model. Dimensional information are available on the TDR

19. 5th step: Barrel definition consequences
For Videau
For Tesla !
Total ECAL barrel length need to be shorter to fit in the HCAL barrel length either by reducing one ECAL size by a large amount (choice made for calculation) or by reducing each module by a smaller amount
Provided ECAL and HCAL have the same length in Z. Hence no modification for the ECAL are needed.

20. 6th step: deformation mechanism
For Videau
Some figures
For Tesla 19mm absorber
Some figure
Mass used for the study
ECAL mass: 21.12t
HCAL mass: 92.18t
Detector mass: 36.8t
Total barrel mass
ECAL mass: 105.6t
HCAL mass: 460.9t
Detector mass: 184t
Total mass: 750.5t
Mass used for the study
ECAL mass: 44.92t
HCAL mass: 235.3t
Detector mass: 71.3t
Total barrel mass
ECAL mass: 89.8t
HCAL mass: 470.6t
Detector mass: 142.6t
Total mass: 703t
About 15% difference in ECAL mass
About 8% difference in total mass
The total masse involved in the simulations are different

21. 6th step: deformation mechanism
For Videau
For Tesla
Max displacement of 0.9mm
Max displacement of 6.0mm
Beware of comparison difficulties due to all previously mentioned differences

22. 6th step: deformation mechanism zoom
For Videau
For Tesla
Max displacement of 6.0mm
Max displacement of 0.9mm
Frictionless supports are used for the rail and cylindrical supports

23. 7th step: ECAL gap analysis
For Videau
ECAL flange displacement
For Tesla
ECAL flange displacement 2 2 1 1 3 3 8 8 4 7 4 7 5 6
Max displacement of ECAL flanges : 0.51mm
Max displacement of ECAL flanges : 5.6mm 6 5
One can see a difference between the two cases with a ratio of about 10.9 between the Ecal module flanges displacement

24. Conclusion:
Provided differences shown along this presentation, comparison of designs on the ECAL assembly is impossible:
ECAL size
HCAL size
Support definition
Absorber thickness
Detector weight
Dimensions and technologies should be disentangled to provide 2 comparable HCAL designs to be able to compare consequences on ECAL assembly.
Up to date CAD model must be provided to go further and converged towards comparable studies

25. Back up

26. Preliminary results: assembling clearance analysis (initial clearance definition)
J1 = 2.5mm
J2 = 45mm h
J1 = clearance between modules for the ECAL J2 = Clearance at ECAL edges between ECAL and HCAL h = height of the rails 30mm

27. Preliminary results: assembling clearance analysis (assumptions)
Transverse flaw of modelling is not taken into account as it doesn’t represent the real behavior of the structure.
Flanges are supposed to close to the real behavior of the ECAL module at the corner area (as shown in first part of this presentation)
All previously mentioned assumptions.
Beware of the transverse behavior along z axis in the solid 3D model compare with the initial shell model shown in the first part.

28. Preliminary results: assembling clearance analysis (calculation method)
We assume that the plane in green remains flat after loading
We determine the equation of the plane and we calculate the distance of points M and N from this plane
This calculation is done only on one side of the ECAL assuming that we have a symmetric behavior M

29. Erratum:
Support interpretation and transposition from gothic to roman in tesla model were misunderstood in past models and calculations.
Results in displacement were over estimated for the roman version in former presentation.
We agreed on using only model provided by each group and not changing things.
Correction could be applied when receiving new Tesla roman version and results consistency is now better.
Further exchange would help the improvement process

30. Preliminary analysis of ECAL and HCAL assembly: Tesla Gothic

31. Calculations assumptions:
Shell model for the ECAL is simplified by solid model with 2 flanges (cf. first part)
Solid model has been determined based on 12 o’clock shell model of the ECAL module
Other ECAL module orientation have not been validated yet.
ECAL modules are perfectly attached to the HCAL through rails.
Total mass involved in the model do not take into account cassettes
Geometrical and fixation simplifications
Shell model for the HCAL « Tesla Gothic» generate numerical singularity points
Note : ECAL dimensions are slightly different from the HCAL Videau design in order to ensure the same initial assembly clearance and get comparable results.

32. Preliminary results: displacement with two ECAL rings Tesla Gothic
In this study we added one ring of ECAL module (i.e. 2 rings of ECAL modules)
total weight of about 275t
Cassette weight within the HCAL is not taken into account.

33. Preliminary results: displacement with two ECAL rings Tesla Gothic
Total displacement rises from 5.2mm (1 ECAL ring) to 5.7mm (2 ECAL rings)
Adding one ECAL ring seems to increase the total displacement by about 10%