First international Design Review of the MYRRHA accelerator. Spoke Cryomodule Design Bruxelles- 12/13 November 2012 Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 SUMMARY Introduction General Specifications and Overview. Spoke Cavity Design. Power Coupler Design Cold Tuning System Design Magnetic Shielding Design Cryostat Design Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 INTRODUCTION The main objectives for the first Mid-Period were : Preliminary design of auxiliary components Power Coupler- OK (Optimization remains) CTS OK - (Optimization remains) Magnetic Shield - Only conceptual Preliminary design of spoke Cavity : RF design - OK Mechanical design - in-work (close to completion) Cavity Helium tank - only conceptual Preliminary design of Cryostat Conceptual design fixed
Cryogenic design fixed (in collaboration with ACS Task 4_2) Preliminary Overall sizing OK Providing a first CAD model of the complete Cryomodule -OK Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 General Specifications and Overview MAX T3_3 = Detailed design of the Spoke CM for End 2013 Spoke Section Reference pattern Two Cells Spoke Cavity @ 352.2 MHz, b geom = 0.35 T Op = 2 K, P mean loss RF = 10 W P max RF losses fault tolerance ~ 17 W E acc max nominal = 6,2 MV/m E acc max fault tolerance = 8,2 MV/m 2 Cavities per CM P Load = 2 to 16 KW CW . P nominal max = 8 KW P max fault tolerance = 16 KW No Focusing components inside CM P Loss Static = 5W/m @ 2K P max cavity helium tank = 1.5 bar
P design cavity helium tank = 2 bar Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 SPOKE CAVITY (1/4) SPOKE BAR GEOMETRY : feedback from the two SingleSpoke resonators and Triple-Spoke resonator fabrication (EURISOL) Base (H field area): no racetrack shape 3D weld seams are not easy (Spoke D weld seams are not easy (Spoke bar-to-cavity body connection) no cylindrical shape Hpk too high Conical shape is chosen Center (E field area): racetrack shape is ok Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 SPOKE CAVITY (2/4) GOALS Epk/Eacc < 4.4 Bpk/Eacc (mT/MV/m) < 8.3D weld seams are not easy (Spoke CST MicroWave Studio 2012 Model created with the 3D weld seams are not easy (Spoke D CAD
tools of MWS Symetries: , BC: Magnetic planes, Tetrahedral mesh, Nb tetrahedrons~10 000 1st mode calculated (TM010) Optimizedof RFaparameters Optimisation dozen parameter Optimal beta Vo.T [MV/m] @ 1 Joule & optimal beta Epk/Ea Bpk/Ea [mT/MV/m] G [Ohm] r/Q [Ohm] Qo @ 2K for Rres=20 n Lacc=0.315m=optimal beta x c x f Pcav for Qo=2 E+09 & 6.4 MV/ 0.3D weld seams are not easy (Spoke 7 0.693D weld seams are not easy (Spoke 4.29 7.3D weld seams are not easy (Spoke 2 109 217 5.2
E+09 Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 SPOKE CAVITY (3/4) Epk 5mm 3 4 = v a Lc Bpk Next steps: - Qext calculation - Lorentz forces detuning factor - Mechanical optimization Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 SPOKE CAVITY (4/4) Preliminary mechanical FE simulations (ANSYS) have been performed on Model 0. Tenue to Vacuum (1 bar) 50 Mpa (V.M)
With Donut stiffener Mechanical longitudinal Stifness 5000 N/mm 25 Mpa for 1 mm elongation Buckling Critical Pressure 2.5 bars Specification : P max inside helium Tank = 1.5 bars Mechanical Eigen mode 60 Hz First mode with non global deformation RF frequency shift. (Without Donut Stiffener) Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 POWER COUPLEUR (1/2) A Power Coupler 350 MHz, 20 kW CW (designed), 50 W. WARM WINDOW Was manufactured, in the framework of Eurotrans and successfully tested at 8 kW (amplifier limitation) CW on a 350 MHz, beta 0.15 Spoke cavity in a Cryomodule configuration. The Design (SNS Type) will be kept as if for MAX
Basis for design 2 CF16 ports for vacuum measurements. 1 port for electron emission measurement pick up 1 water cooling loop Plain Copper Antenna CF 63 on cavity Thermal interception at 70 K (~15 W solid conduction) and ~ 10 K (~3 W solid conduction) Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 POWER COUPLEUR (2/2) A conservative outer conductor lenght of 300 mm was taken to start the cryomodule design. Detailed simulations, for the thermal aspects remain to be done. A passive barometric compensation system (ESS Type) was studied in order to balance the atmospheric pressure force between the Coupler and the cavity train. 80 K Thermal interception Vacuum vessel assembly flange Thermal contraction bellow Barometric compensation bellow 350 MHz Coax line Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012
Same Area 5/10 K Thermal interception Warm Window block Fixation rods to coupler (mooving point) Fixation rods to vacuum vessel fixed point) Cold Tuning System One CTS was designed and tested on a Beta = 0.15, 350 MHz Spoke cavity in the framework of Eurotrans. The main parameters ( Cavity RF frequency sensitivity, Stiffness, Helium Tank relevant dimensions) are similar with the MAX Spoke cavity. This design is taken for the Spoke MAX CTS Design. In addition an optimized design, in term of stiffness, is under study on a similar CTS for ESS 350 MHz Spoke cavities. General studies on reliability (C&C, reliability of stepping motor and reductor) are conducted in the frame of the MAX Task T3_1. The CTS detailed Design will be achieved once the Cavity Helium Tank is completed.. CTS (CEA Soleil Type) for Eurotrans 350 MHz Spoke cavity Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012
Magnetic Shielding No detailled study is done yet on the Magnetic Shielding. No simulation on the magnetic field effect and the sizing of the Shield. As conceptual design we assume that the Magnectic Shield is : - Made of Cryoperm - Cooled down actively During Cool down phase the Cryoperm is first - Composed of two skins cooled and reach the optimal temperature (below 70 K) before the cavity becomes SC. In Stationary operation the shield only attached to the cavity helium tank reach an equilibrium temperature. Assemblies of the different parts of the shield are made with screws Requires long cooling tube ~ 8 m per cavity. This concept was succefully tested on SPIRAL2 CM B. SP L A IR o C 2 Cavity Cool Down Phase
t p nc e A more practical concept as trapping the cryoperm inside the Helium Tank may be considered. Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 Cryostat Design / Overview Level measurement and relief valves circuit chimney Copper thermal shield (40/80K 4/3 bars) Cryogenic line connection 2 K phase separator reservoir Actively cooled down magnetic shield Cold Tuning System Cavity pumping port
Sliding and adjustable fixture to cavity train supporting frame (TTF Type) Warm valve (No Cold Valves) 5/10K heat interception loop Cavity train supporting frame Adjustable supporting posts Barometric compensation Coaxial 350 MHz Line Power couplers Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 Cryostat Design / Overview Diagnostics box position and size ?. Longitudinal gain of space is still possible. Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 Cryostat Design / Assembly Cold Mass Inside Clean Room (Iso 4) Outside Clean Room
Cavity + Coupler, first assembled on Clean Room trolley. Different components assembled on the CM suporting frame. This frame goes outside and inside Clean room Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 Cryostat Design / Assembly - Cryostating Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 Cryostat Design / Cryogenic Loops Internal CM circuitery Q T max F Int & L t CD DP max 40/80 K Loop Cool Down (Ghe 4/3 bars) 2g/s
NC 10 mm, 15 m 9 hr 115 mbar 40/80 K Loop Stationary (Ghe 4/3 bars) 110 W 86,2 K 10 mm, 15 m NC 4 mbar 5/10 K Loop (Lhe 3/1 bar) 15 W 10 K NC 1 mbar
0.3 hr 180 mbar Mag. Shield Cool Down (LHe 1,2/1 bar) 10 mm, 8 m Cavity Cool Down (Lhe 1,2/1 bar) 1,2 hr Cavity Stationary 30 W <10-1 mbar Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 Cryostat Design / Pressure Security Accident : Insulation Vacuum breakage. m= 742 g/s T fluid out < 20 K P cav max =1.5 bar
Volume LHe ~ 100 litres Surface He loop ~ 2,6 m2 q = 6 kW/m2 (CERN, Conservative) 1 x Burst Disk (K=0.6, F = 60 mm) P discharge = 1.33 bar+/- 10% m max = 750 g/s @ T > 20 K 2 x Relief Valve (Circle seal type 500 F 1 ) P oppening = 1.15 bar+/- 5% m max (each)= 120 g/s @ T = 20 K. Prevent overpressure from Cool Down operation, Quenchwithout breaking the Burst Disk Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 Cryostat Design / Thermo-Mechanical Evaluations Conservative (To Be optimized) Q* 300K70K Q 70K2K K Q 70K10K Q 10K2K K Cavity frame- Solid Conduction (With 5K/10K Heat Sink)
22,6 W NC 1,6 W 0.11 W Power Coupler - Solid Conduction 30 W NC 6W < 0.1 W Beam Tube solid conduction (300K2K Transition) 1,6 W 0,1 W NC NC Burst disk pipe Solid Conduction (to be evaluated) <2W
< 0.1 W Thermal radiation (30 layers MLI @60K ; 10 layers MLI @2K ) 30 W 0.2 W NC NC NC NC < 2W ?? < 2W ?? (6W/m2) Thermal radiation (Beam tubes, measurement chimney) 2,74 W Thermal radiation Power Couplers (to be evaluated) < 5W ???
Instrumentation, Wiring (to be evaluated) <5W (0,06 W/m ) 2 0.1 W < 0.5 W Q 70 K < 100 W To be reduced, Q 5K/10K < 10 W, Q 2K K < 3,2K W *Require Optimizations Cavity Frame (To be Optimized) DX D Y* D Z* s V.M. @ 300K (100 Kg/Cavity) -0,1/+0,14 -0,9/+0,9
-0,6/+0 78 MPa @ Cold ( 100 Kg/Cavity + thermal contraction) -3,6/+0,2 -0,5/+0,5 -2/+0 78 MPa Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 Cryostat Design / Accelerator Hall Cross section The vertical position of the LINAC depend on other components as elliptical cavity CM. Diameter, coupler lenght and Coupler doorknob and wave guides are in a first approximation compatible with a 1,5 m beam axis height. 700 MHz Elliptical cavity DoorKnob RF amplifiers, electronicHall Valve box not designed yet. Can be optimized to gain space (parallepipedic instead of cylinder). Height of the hall remains to be checked taking into account handling (tools, strategy) of the different
components. P ry na i im rel L u CT A IN Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012 el n n io ns e Dim ns Conclusions
Conceptual and preliminary designs achieved for the main components. Cavity RF optimization achieved, mechanical optimisation in-work Components (CTS, Coupler, Cryostat)optimization to be achieved in June 2013 CAD detailed design & assembly tooling from June 2013. A Spoke cavity prototype without helium tank is planed to be manufactured (order before end 2012). Cryogenic tests will be performed in 2013 in order to validate the RF Design and the Manufacturing process. Spoke Cryomodule Design - H. SAUGNAC - First international Design Review of the MYRRHA accelerator- Bxl 12/13 November 2012
