18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

1/14

CLIC Two-Beam Module type 0. RF Network.

Drive-Beam

Main-Beam

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

2/14

Model CATIA is consist of:

2 Waveguides and Cooling Tubes 3 Reinforcements 2 Choke Mode Flanges 2 Hybrids 2 Compact Loads 4 Splitters 16 Input Waveguides 26 Flanges

Model CATIA Model ANSYS

Compact Load

Hybrid

Splitter

Input Waveguides

Waveguide and Cooling Tube

Choke Mode Flange

Model ANSYS is consist of: 2 Waveguides and Cooling Tubes 3 Reinforcements 2 Choke Mode Flanges 2 Hybrids 2 Compact Loads 4 Splitters 16 Input Waveguides 26 Flanges → 8 Flanges

Reinforcements

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

3/14

Boundary conditions: Fixed supports on Waveguides and Input Waveguides.

Fixed supports on the 4 surfaces

Fixed supports on the 4 surfaces

Fixed support → Tx = 0, Ty = 0, Tz = 0, Rx = 0, Ry = 0, Rz = 0 (T Translation, R Rotation)

Fixed supports on the 4 surfacesFixed supports on the 4 surfaces

1rst Subassembly

2nd Subassembly

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

4/14

Mechanical loads:

I. Earth Gravity on the RF Network. II. Vacuum inside of the RF Network.

1) A force of 340 N both sides of bellows due to vacuum can be divided up as follows:a) Application of a pressure of 1 bar (0,1 MPa) on all Waveguide surfaces.

The result of all this is a force of 38,6 N along the axis of CMF (Pumping Effect).b) Application of a force of 301,4 N on the Bellows Flange corresponding to a pressure of 1 bar on the Choke

Mode Flange (taper 1) and the Bellows Flange.

1rst and 2nd Subassembly

Hybrid

Waveguide

Force of 301,4 N.

Pressure of 1 bar on all Waveguide surfaces (Red).

Bellows Flange

Resultant force of 38,6 Nalong the axis of CMF.

CMF (taper 1).

Axis of CMF

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

5/14

Mechanical loads:

c) Application of a pressure of 1 bar (0,1 MPa) on the Hybrid on all its external surfaces. The result of all this is a force of 64,8 N along the axis of the CMF (Pumping Effect).

d) Application of a force of 275,2 N on the Bellows Flange corresponding to a pressure of 1 bar on the Choke Mode Flange (taper 2) and the Bellows Flange.

1rst and 2nd Subassembly

Hybrid

Waveguide

Force of 275,2 N.

Pressure of 1 bar on all Hybrid external surfaces (Red).

Bellows Flange

Resultant force of 64,8 Nalong the axis of CMF.

CMF (taper 2).

Axis of CMF

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

6/14

Mechanical loads:

1rst and 2nd Subassembly

2) Application of a pressure of 1 bar on all the external surfaces of Splitters and Input Waveguides.

Hybrid

Input Waveguides Pressure of 1 bar on all external surfaces (Red).

Splitters

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

7/14

Results:

Contact

Contact

1rst Subassembly 2nd SubassemblyGap of 3 mm before deformation.

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

8/14

Results: 1rst Subassembly

24,2 MPa

51 MPa

Approximately 12 MPa

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

9/14

Results:

69 MPa

20 MPa

Approximately 7 MPa

2nd Subassembly

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

10/14

Results: Deformation following Y axis

1rst SubassemblyHybrid Waveguide

2nd Subassembly

Y Y

Y Y

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

11/14

Results: Deformation following X axis

2nd Subassembly1rst Subassembly

X X

X X

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

12/14

Results: Deformation following Z axis

1rst Subassembly 2nd Subassembly

Z Z

Z Z

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

13/14

Results: Pictures taken at BODYCOTE on 2nd subassembly without reinforcements.

Before vacuum

Under vacuum

Deformed bellows.Result of compression (negative Z axis and positive X axis).

Under vacuumBefore vacuum

Y

X

Z

18/04/12 Arnaud ACKER

Mechanical Analysis of RF Network

14/14

Conclusion The greatest deformations are found on the Waveguides and CMF region:

1) The phase error could appear.2) Friction forces introduced if 2 tapers of CMF are in contact.

The greatest stresses are found in CMFs and at the feet of Waveguides (around PETS Compact Couplers zone):

1) CMF → 51 MPa for the 1st CMF and 69 MPa for the 2nd CMF.2) WG → 24,2 MPa for the 1st WG and 20 MPa for the 2nd WG.

Reinforcements ribs are not sufficient to provide needed the Waveguides stiffness. I would recommend to re-design the Reinforcements or find an alternative solution.

Concerning the CMF. The use of an equivalent cylinder for the simplification of bellows is not a recommended method since the results are not similar to the reality.

Bellows