TIARA PP
TIARA Final Meeting
27th November 2013 – Daresbury
TIARA-PP WP 9 : TIHPAC
Test Infrastructure for High Power Accelerator Components
Sébastien Bousson
(CNRS/IN2P3/IPN Orsay)
On behalf of the WP9 participants: CERN, IPNO, ESS
A little reminder : WP 9 Main Goal
WP9 raised from the following consideration: What would be the
necessary test infrastructures for developing the key elements of the
EURISOL project ?
EURISOL is the next generation of a facility aiming at the production of
radioactive ion beams (RIB) using the ISOL technique.
Among all the technical challenges raised by this project, 2 key
components have been identified which will require an important R&D
program and an intense experimental program to design these
components for the Eurisol requirements:
 The multi-MW target complex
 The low beta superconducting cavities (used for the driver and for
the post-accelerator linac)
Sub-Task 1:
Multi MW target development
Sub-Task 1: Multi MW irradiation facility
The main idea of sub-task 1:
Develop a versatile Multi MW Irradiation Facility for complex target testing
to be tested with beams at all possible locations, meaning over a wide
range of beam power (several kW to MW).
Full scale test of the final MMW target available only in the final facility !
Achieving the design of the full scale target (ex. 4 MW for Eurisol) will
require several partial tests: sub-components, irradiation at lower power,
material testing, specific instrumentation developments…
For that, an irradiation facility for complex target testing is required,
hosting an adaptable target in order to test concepts, instrumentation,
material science (like fatigue, heat transfer), safety (primary/secondary
fluid interactions), etc…
The target itself should be adaptable, but keeping all services (heat
exchanger, loop…) externalized (i.e. common for all target geometries).
Sub-Task 1: Multi MW irradiation facility
Break-down of items/systems to be tested:
K. Samec
Sub-Task 1: Multi MW irradiation facility
The details of the huge design work of this facility achieved by the
CERN teams have been presented yesterday in Yoann Fusco’s talk
Sub-Task 1: Multi MW irradiation facility
The details of the huge design work of this facility achieved by the
CERN teams have been presented yesterday in Yoann Fusco’s talk
Sub-Task 2:
low beta cavity test cryomodule
Sub-Task 2: low beta cavity test cryostat
Before assessing that a SC cavity is validated for an operational use in an
accelerator, the final experiment is a cryogenic test at nominal RF power of
the fully equipped cavity (power couplers, cold tuning systems…)
Very few “accelerator configuration” test cryostat are existing in Europe
and they are only designed for elliptical cavity testing (CHECHIA , HOBYCAT,
CRYHOLAB).
Such a cryostat, specific
and devoted to low beta
SC cavities will be a useful
complementary
equipment.
Sub-Task 2: low beta cavity test cryostat
User requirements have been collected to establish specifications for this
versatile low beta cavity test cryostat.
Identification of the user requirements for the test cryostat:
4 main categories of requirements have been identified:
1.
2.
3.
4.
Geometric dimension (cavity type and physical capacity)
Integration of couplers and cold tuning system
Cryogenic requirements
Assembly requirements
EU Project driven requirements:
EURISOL, MYRRHA, ESS, IFMIF, HIE-ISOLDE
With potential interest for:
LRF (HUELVA), ion or RIB post-accelerators,…
… and many others outside Europe !
Sub-Task 2: low beta cavity test cryostat



Different cavity geometries (type), beta, and frequencies
o Half-wave resonators
o Quarter wave resonators
o Spoke cavities (single, double or triple spoke)
o Others: re-entrant, CH,…
Integration of the possibility to mount a superconducting magnet for
residual magnetic field test or potential pollution during assembly
Vertical or horizontal positioning to be envisaged for some cavities
Double
spoke
Triple spoke
HWR
Single spoke
QWR
QWR
HWR
Sub-Task 2: low beta cavity test cryostat
Integration of couplers and cold tuning system
Integrating couplers and tuners for different geometries is the main
concern for this versatile cryostat


Power couplers: For all cavity type, geometries are very different: the
cryostat should have the possibility to have couplers located on the
the bottom or on the side of the module (on top: option discarded).
Cold tuning system: Also very different from one to each other:
tuning by deformation, volume insertion, integration of piezo
actuators; using cold or warm motors .
Only a cryostat with high flexibility (many openings & access) can solve
this issue.
Sub-Task 2: low beta cavity test cryostat
Cryogenic specification



Operating temperature: 4.2 K or depressed He bath (2 K typically)
Power: the cryogenic system should be able to handle about 80 watts
(in average) of dissipated power at 2 K
Cooling time: in order to avoid the ”100 K effect”, the module should
be able to cool down rapidly (typically, not more than one hour
between 130 K and 70 K)
Assembly requirements


The cryostat assembly has to be feasible in a huge variety of clean
rooms : height requirements not too important, as simplest as
possible assembly tooling, lowest possible amount of material
entering in the clean room (pollution control) => concerns with the
clean air blowing direction
No requirements on any alignment device (has only meaning in a real
accelerator module)
Sub-Task 2: low beta cavity test cryostat
Preparation and assembly fundamentals

The volume constituted by the cavity and its power coupler has to be
prepared in dust free conditions. The cavity and its power coupler, up
to the coupler window, are assembled inside an iso4 clean room.

The cavity volume is then evacuated to secondary vacuum, inside the
clean room, and closed with an insulation valve able to be cooled
down at cryogenic temperature (typically full metallic UHV valve).

The cavity and its couplers are then inserted inside the cryostat
outside the clean room.
Sub-Task 2: low beta cavity test cryostat
Preparation and assembly fundamentals
Two different cryostat
configurations have
been envisaged

Option #1: Insertion along the Horizontal axis on a cylindrical Cryostat

Option #2 : Insertion from the top on a rectangular Cryostat
Cryostat type
Pros
Cons
Option 1
(horizontal)
Vacuum vessel low cost
• require a special frame for cavity string
insertion (different for each cavity type)
• large diameter (large test stand footprint)
Option 2
(top loaded)
• more versatile
• reduced dimensions
• cost
Sub-Task 2: low beta cavity test cryostat
Vacuum vessel design
1/ Rectangular section
10 mm thickness not enough
(buckling)

Displacement
Stress
Sub-Task 2: low beta cavity test cryostat
Vacuum vessel design
2/ With arc of a circle
 10 mm thickness
Displacement
Stress
Sub-Task 2: low beta cavity test cryostat
Vacuum vessel design
3/ Polygonal shape
 several geometries studied
Sub-Task 2: low beta cavity test cryostat
Vacuum vessel design: polygonal shape is the final choice
Even with this shape, stiffeners are still
required, but of a simple shape, much easier
than the one required for a rectangular
shape.
Sub-Task 2: low beta cavity test cryostat
Cryostat main components
Sub-Task 2: low beta cavity test cryostat
Integration of the cavity string
1 - The cavity string coming from clean room is
fixed to the special frame of the Cryostat top
cover. A crane and a simple supporting frame is
required for handling the different parts. Partial
cryogenic tubing is then assembled.
Instrumentations of the cavity string and assembly
of the cold tuning system may be performed at
this stage.
2 - The thermal shield is assembled as well as the
remaining instrumentations or cryogenic tubing.
The component at this stage composes the
Cryostat cold mass.
3 - The Cold mass is inserted inside the Cryostat vacuum vessel from the top (with a crane)
4 - The Cryostat vacuum vessel exhibits large openings, on the top and the bottom as well as on
the sides to allow access and assembly of the various geometry of auxiliary components. It is
possible to assemble cavities with horizontal (on the side) or vertical (bottom/top) Power
Couplers. The assembly of all the remaining auxiliary components or instrumentation are done
at this stage.
Sub-Task 2: low beta cavity test cryostat
View of the cryostat integrating a spoke cavity
Sub-Task 2: low beta cavity test cryostat
View of the cryostat integrating a quarter-wave resonator
Sub-Task 2: low beta cavity test cryostat
View of the cryostat integrating a half-wave resonator (horizontal)
Sub-Task 2: low beta cavity test cryostat
Cryostat final dimensions
Sub-Task 2: low beta cavity test cryostat
Conceptual study of the valve box:
 The conceptual work is done (the detailed design is not integrated in
the Tiara work list)
 Only missing point is the specific cooling line for the SC magnet
 At this stage, no specific requirements will be integrated (like
magnetic shielding pre-cooling for instance), but the valve box will be
compatible with the integration of such specific cooling lines.
 Interface with the cryostat is from the to; then the cold box could be
located either on the side or on the top of the cryostat.
Sub-Task 2: low beta cavity test cryostat
Concept of the valve box for the cryostat
WP 9 Work Status: Gantt chart
WP 9 Work Status: task completion
Task
9.1
9.1.1
9.1.1.1
9.1.1.2
9.1.2
9.1.2.1
9.1.2.2
9.2
9.2.1
9.2.1.1
9.2.1.2
9.2.2
9.2.2.1
9.2.2.2
9.2.3
Short Name
M-MWIF
DSIF
IIF
SIF
DSIF
PDIF
TDIF
DCTC
DSTC
IUR
STC
DTSCS
PDTSCS
ADTSCS
CDCCB
Description
Multi MW Irradiation Facility for complex target testing
Definition and Specification of the Irradiation test Facility
Identification of the Irradiation test Facility
Specifications of the Irradiation test Facility
Design Study of the high power Irradiation test Facility
Preliminary Design study of the high power Irradiation test Facility
Technical Design report on the high power Irradiation test Facility
Design of a fully equipped low beta Cavities Test Cryostat
Definition and Specification of the low beta SC Test Cryostat
Identification of the User Requirements
Specifications of the low beta Test Cryostat
Design of the vacuum Tank, Shielding, and Cavity supporting System
Preliminary Design study Tank, Shielding, and Cavity supporting System
Advanced Design study Tank, Shielding, and Cavity supporting System
Conceptual Design of the associated Cryogenic Cold Box
% Achievement
90 %
100 %
100 %
100 %
90 %
100 %
90 %
85 %
100 %
100 %
100 %
85 %
100 %
75%
90 %
WP 9 : Deliverables
• WP9 Deliverables consists in 2 engineering report describing the detailed
designs of the two equipments
• In both cases, the design work is almost achieved, but the reports have to be
completed for the (nominal) end of Tiara-PP !
Deliverables
Num
Nat
Name
D9.1
R
TDIF
D9.2
R
TDCC
Description
month
Expected
Technical Design Report of the Multi-MW test
Irradiation Facility
36
37
Technical Design Report on the SC Cavity test Cryostat
33
36
Conclusions
• An important design work was completed in Tiara-PP on two testing
facilities:
• a Multi MW Irradiation Facility for complex target testing
• a versatile cryostat for fully-equipped low beta SC cavities
• Even if the need of such equipments was raised by Eurisol, many
other projects, in EU or worldwide, would benefit from the existence
of such facilities.
• A cost estimate for each equipment will be done and indicated in the
final report, but the order of magnitude is about 1 M€ for each
Thanks to all the contributors
to the TIARA WP9:
Teams from CERN, IPNO
and ESS
Long Live TIARA !