1. IT & D1 HeII cooling-variants
WP3 Meeting
(24th of April 2013)
IT & D1 HeII cooling-variants
R. van Weelderen (CERN)

2. Overview Variants for placing cryo-equipment considered
Actively cooled parts: ∆T, HX-size as function of total heat load
Passively cooled parts: Conduction area as function of heat load per meter
Summary of requirements as function of HeII- cooling-variant

3. Variants for placing cryo-equipment considered (1 of 4)
actively cooled
passively cooled
Phase-separator &
Piping entries/exits
Phase-separator &
Piping entries/exits
Possible QRL-jumper
SM &
QRL-jumper
Q1,Q2a,Q2b,Q3: actively cooled for about 41 m, double-HXs (80 mm Ø holes) needed
CP & D1 : passively cooled for about 16 m, no HXs needed

4. Variants for placing cryo-equipment considered (2 of 4)
actively cooled
passively cooled
Phase-separator &
Piping entries/exits
Phase-separator &
Piping entries/exits
Possible QRL-jumper
SM &
QRL-jumper
Q1,Q2a,Q2b,Q3+CP: actively cooled for about 49 m, double-HXs (80 mm Ø holes) needed
D1 : passively cooled for about 8 m, no HXs needed

5. Variants for placing cryo-equipment considered (3 of 4)
actively cooled
passively cooled
actively cooled
Phase-separator &
Piping entries/exits
Phase-separator &
Piping entries/exits
Possible QRL-jumper
SM &
QRL-jumper
Phase-separator
Piping entries/exits
Q1,Q2a,Q2b,Q3: actively cooled for about 41 m, double-HXs needed
CP : passively cooled for about 8 m, no HXs needed
D1 : actively cooled for about 8 m, double-HXs needed

6. Variants for placing cryo-equipment considered (4 of 4)
actively cooled
actively cooled
Phase-separator &
Piping entries/exits
Phase-separator &
Piping entries/exits
Possible QRL-jumper
SM &
QRL-jumper
Phase-separator
Piping entries/exits
Q1,Q2a,Q2b,Q3: actively cooled for about 41 m, double-HXs needed
CP,D1 : actively cooled for about 16 m, double-HXs needed

7. Actively cooled IT-parts
Total power extraction limited by :
# (2)
size (80 mm holes)
of the HXs
For both variants 1 & 2, we can extract the total IT-CP-D1 heat up to a maximum of 550 W with a ∆T < 100 mK.

8. Passively cooled parts
Variant 1: D1+CP conduction area > 300 cm2
Variant 2: D conduction area > 130 cm2
Variant 3,4: CP conduction area > ~ 100 cm2 (t.b.c)

9. Variant 3 and 4 HX comparison
Give the saturation temperature at the T of the D1 and CP helium bath is dominated by the available HX-Area and Kapitza resistance of the Cu- surfaces:
2xHXs holes
Variant 3
Variant 4
49 mm -
1.925 K
54 mm
1.910 K
59 mm
1.900 K
64 mm
1.889 K
69 mm
1.963 K
1.882 K
74 mm
1.950 K
< K
79 mm
1.940 K
‘-’ : means HX overflowing and/or T > 2.0 K, non feasible configuration
Variant 3, with HX-holes > 69 mm is critically dependent on the HX-area and variations in Kapitza resistance of the Cu surfaces risky configuration
Variant 4, with HX-holes penetrating D1 and CP is more robust and can do with HX holes down to 49 mm

10. Variant 1
Variant 2
Variant 3/4
Power limit (with max HX holes of 80 mm)
550 W (Q1-D1)
vapour velocity constraint
550 W (Q1-Q3) +
~ 160 W (CP-D1) =
710W Area constraint
Q1-Q3 HXs
Q1-Q3 Free Area
Q1-Q3 Cryostat Pumping line
2x80 mm holes
~ 150 cm2 mm
CP HXs
CP Free Area
CP Cryostat Pumping line
none
> 300 cm2
None or > 2x49-80 mm holes
~ 100 cm2
D1 HXs
D1 Free Area
D1 Cryostat Pumping line
~ 130 cm2
> 2x49-80 mm holes
~ X mm
Phase separator
& piping entries/exits
Q1-end
Q3-CP
CP-D1
CP-D1 or Q3-CP
QRL-jumpers SM

11. Summary
If Qtotal < 550 W: Variant 2 if 80 mm holes in CP allowed, if not Variant 3/4
If 550 W < Qtotal < 710 W: Variant 3/4, T-D1 will approach 2.0 K, if possible at least 2x49 (preferably 80 mm) mm holes through D1 and CP
Qtotal > ~710 W becomes difficult!