1. Generic Cryo HX Options
R. van Weelderen (CERN)

2. Cryo Generic Layout Possibilities
Inner triplets will be actively cooled via 2 parallel HX
D1 and MCBXC cooling could be either active as well or passive via conduction
Options considered:
D1 and MCBXC passively cooled
D1 passively cooled
All actively cooled
Room for cryo services needed at:
Q3 to MCBXC (option 1)
MCBXC to D1 (option 2)
D1, non-IP end (option 3)
Entry at D1, non-IP end + D1 bypass to a)/b) (option 1/2)
Magnet
Nb3Sn, length (m)
NbTi, variation (m) Q1
8.5
10.63
Q1 to MCBXD
1.92
MCBXD
1.31
MCBXD to Q2a
0.42
Q2a
6.77
8.69
Q2a to Q2b
2.05
1.91
Q2b
Q2b to MCBXD
MCBXD to Q3 Q3
Q3 to MCBXC
MCBXC
2.00
MCBXC to D1
4.28
D1 (magnetic length+2x0.5m)
8.65
7.3
Total
56.7
63.4
D1 + MCBXC conductive length
16.9
15.5
D1 conductive length
12.9
11.6

3. Two Phase HX Inner Diameter Options
Assumptions:
Total heat load of D1 + MCBXC and IT: 500 W in all configurations
Cold source at IT pumping line: K
T-budget for HX of actively cooled magnets: up to K
T-budget for conduction cooling: 50 mK (from K to K)
D1 and MCBXC (passive)
D1 (passive)
All (active) D1
no HX, Free area: 175 cm2
no HX, Free area: 120 cm2
2 x HX: 68 mm ID, Free area t.b.d.
MCBXC IT
Consequences:
The two-phase HX sizing is mainly dependent on total heat load: 68 mm ID in all cases
For all actively cooled magnets and interconnects the HX’s must be fully continuous (no bends allowed!)
Thermal budget for actively cooled magnets (coil – HX): ~ 170 mK max (Tλ – K)
Thermal budget for passively cooled magnets (coil – HX): ~120 mK max (Tλ – K)
Piping through magnets & cryostats to be sized (complete PID to be made) depending on choice of Cryo implementation