Phase 1 FPix Cooling Loop Design

Phase 1 FPix Cooling Loop Design

Kirk ArndtFebruary 1, 2012

(on behalf of CM Lei, Erik Voirin, Simon Kwan, Joe Howell)

CMS Phase 1 FPix Cooling Loop Design 2

Typical bending R for tubing beyond ring = 1/8” = 6.35mm

1-Feb-12

Coupler bonded 2 tubing together permanently, further

development and proof of feasibility needed

HD Tubing AssemblyLength = 3,209 mm

Couplers bond tubing between half-rings permanently,

further development and proof of feasibility needed

Tubing within Rings

CMS Phase 1 FPix Cooling Loop Design 31-Feb-12

Tubing Length Info

Outer-Outer Outer-Inner Inner-Inner Inner-Outer

L (mm) 1134 739 501 835

Outer Outer Outer Inner Inner Inner Inner Outer


1.435mm ID/1.638mm OD SS tubing connects all rings in a Half-Disk in series

To optimize:– examine the ∆T reduction vs. material increase if changing to 1.63mm

ID tubing.– examine the ∆T reduction vs. material increase if changing to parallel

flow to Outer Assembly and Inner Assembly.– conduct a 4-blade thermal test to verify the ∆T from coolant to pixel

modules.– conduct a single tube mock-up CO2 cooling test to verify the ∆T along

the tube with simulated detector heat load.

Baseline Design of HD Cooling Tube


Cooling Calculations for HD1<< Courtesy from Joao Noite >>

1

2 3 4 5

6

7

8

9

10

11

ID 1.435 mm ST Supply DC-DC ST PC ST O-O O-I I-I I-O ST ReturnFlow Path 1->2 2->3 3->4 4->5 5->6 6->7 7->8 8->9 9->10 10->11Qt [W] 0 30.00 0 15 0 61.20 40.8 26.4 39.6 0d [m] 0.002 0.002 0.002 0.002 0.002 0.001435 0.001435 0.001435 0.001435 0.0028lt[m] 1.1 0.9 0.35 0.9 0.95 1.134 0.739 0.501 0.835 2.345t [m] 0.0001 0.0001 0.0001 0.0001 0.0001 0.00005 0.00005 0.00005 0.00005 0.0001kw [W/m.°C] 16 16 16 16 16 16 16 16 16 16

1-Feb-12

ID 1.63 mm ST Supply DC-DC ST PC ST O-O O-I I-I I-O ST ReturnFlow Path 1->2 2->3 3->4 4->5 5->6 6->7 7->8 8->9 9->10 10->11Qt [W] 0 30.00 0 15 0 61.20 40.8 26.4 39.6 0d [m] 0.002 0.002 0.002 0.002 0.002 0.00163 0.00163 0.00163 0.00163 0.0028lt[m] 1.1 0.9 0.35 0.9 0.95 1.134 0.739 0.501 0.835 2.345t [m] 0.0001 0.0001 0.0001 0.0001 0.0001 0.00005 0.00005 0.00005 0.00005 0.0001kw [W/m.°C] 16 16 16 16 16 16 16 16 16 16

Tubing diameters and lengths are the same from point 1 to point 6 before coolant entering O-O,and on the return line from point 10 to point 11.

Ring I-O of the 4 rings is cooled last


0 1 2 3 4 5 6 7 8 9 10-25

-20

-15

-10

Loop Length [m]

Tem

pera

ture

[°C

]

m = 1.87g/s | Qtotal = 213.00W | Pin = 22.10Bar | Tin = -20.00°C | dP = 2.44Bar | dT = 5.52°C

0 1 2 3 4 5 6 7 8 9 1018

20

22

24

Pre

ssur

e [B

ar]

Theory Wall TemperatureTheory CO2 Temperature

Theory CO2 Pressure

ST S

uppl

y

DC-D

C

ST PC ST O-O

O-I

I-I I-OST Return

0 1 2 3 4 5 6 7 8 9 10-25

-20

-15

-10

Loop Length [m]

Tem

pera

ture

[°C

]

m = 1.87g/s | Qtotal = 213.00W | Pin = 21.20Bar | Tin = -20.00°C | dP = 1.58Bar | dT = 4.22°C

0 1 2 3 4 5 6 7 8 9 1019

20

21

22

Pre

ssur

e [B

ar]

Theory Wall TemperatureTheory CO2 Temperature

Theory CO2 Pressure

ST S

uppl

y

DC-D

C

ST PC ST O-O

O-I

I-I I-O

ST Return

HD1 (1.63mm ID)HD1 (1.435mm ID)

100 150 200 250 300 350

10

20

30

40

50

60

70

80

-40°C -30°C -20°C -10°C 0°C 10°C 20°C 30°C

Enthalpy [kJ/kg]

Pre

ssur

e [B

ar]

m = 1.87g/s | Qtotal = 213.00W | Pin = 22.10Bar | Tin = -20.00°C | dP = 2.44Bar | xout = 0.40

100 150 200 250 300 350

10

20

30

40

50

60

70

80

-40°C -30°C -20°C -10°C 0°C 10°C 20°C 30°C

Enthalpy [kJ/kg]

Pre

ssur

e [B

ar]

m = 1.87g/s | Qtotal = 213.00W | Pin = 21.20Bar | Tin = -20.00°C | dP = 1.58Bar | xout = 0.40

liquid starts boiling at ~-17°C corresponding to saturation pressure of 22.1 bar

liquid starts boiling at ~-18°C corresponding to saturation pressure of 21.2 bar

1-Feb-12


HD1 (1.63mm ID)HD1 (1.435mm ID)

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

200

400

600

800

1000

1200

1400

1600

Vapor Quality

Mas

s V

eloc

ity [k

g/m

2 .s]

G = 1156kg/m2.s | q = 11.97kW/m2 | Psat = 21.61Bar | xout = 0.18 | xdryout = 0.57

A D

M

I

SLGS SW

B

O-O

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

200

400

600

800

1000

1200

1400

1600

Vapor Quality

Mas

s V

eloc

ity [k

g/m

2 .s]


A D

M

I

SLGS SW

B

O-I

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

200

400

600

800

1000

1200

Vapor Quality

Mas

s V

eloc

ity [k

g/m

2 .s]


A D

M

I

SLGS SW

B

O-O

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

200

400

600

800

1000

1200

Vapor Quality

Mas

s V

eloc

ity [k

g/m

2 .s]


A D

M

I

SLGS SW

B

O-I

1-Feb-12


HD1 (1.63mm ID)HD1 (1.435mm ID)

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

200

400

600

800

1000

1200

1400

1600

Vapor Quality

Mas

s V

eloc

ity [k

g/m

2 .s]


A D

M

I

SLGS SW

B

I-I

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

200

400

600

800

1000

1200

1400

1600

Vapor Quality

Mas

s V

eloc

ity [k

g/m

2 .s]


A D

M

I

SLGS SW

B

I-O

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

200

400

600

800

1000

1200

Vapor Quality

Mas

s V

eloc

ity [k

g/m

2 .s]


A D

M

I

SLGS SW

B

I-I

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

200

400

600

800

1000

1200

Vapor Quality

Mas

s V

eloc

ity [k

g/m

2 .s]


A D

M

I

SLGS SW

B

I-O

1-Feb-12


HD1 (2.0-1.63-2.8mm ID)HD1 (2.0-1.43-2.8mm ID)

HD1 2.0-1.43-2.8mm 2.0-1.63-2.8mm

Pin 22.1 21.2

dP 2.44 1.58

Wall Tin for ring OO -15 -16.2

Wall Tin for ring OI -15.9 -17.1

Wall Tin for ring II -16.8 -17.8

Wall Tin for ring IO -17.5 -18.2

Wall Tout for ring IO -19.1 -19.1

Wall ∆T for 4 rings 4.2 2.9

Last Ring I-O Vapor Quality at Dryout 0.58 0.64

1-Feb-12 Conclusion: Larger tubing performs better with extra 6% margin from dryout.


3 removable couplings; each weighs 0.7 g2 permanent couplings btw outer & inner rings1 supply + 1 return tube per HD

4 removable couplings2 permanent couplings btw outer & inner rings2 supply + 2 return tubes per HD

Possible Parallel Flow Layout

1-Feb-12

Baseline Serial Flow Layout


Possible Parallel Flow LayoutWant to calculate ∆P & ∆T of parallel flow to Outer and Inner Assemblies with 1.435mm ID tubing in rings


-17.6oC-18.2oC

New I-I start if cooling last

-16.9oC

-19.2oC

IO start IO end II start II endexisting wall temp, IO last -17.6 -19.2 -16.9 -17.6proposed wall temp, II last -16.9 -18.2 -18.2 -19.2∆ T 0.7 1 -1.3 -1.6

HD1 (2.0-1.43-2.8mm ID)

These temperatures were used as the heat sink temperatures

for the blade FEA

These temperatures were used as the heat sink temperatures

for the blade FEA(see next slides)

Study on whether the Inner-Inner ring should be cooling last<< The total ∆T across the 4 rings is the same >>

Existing I-I start if cooling second-to-last

1-Feb-12


Alternative, Inner Inner Ring cooled last:Inner Outer ring temp = -16.9oCInner Inner ring temp = -18.2oCMax Temp on Module = -11.3oC∆T = 6.9 C across the whole model

Comparing results with different heat sink temps TIM conductivity at blade ends = 1 W/m-K

Baseline, Inner Outer Ring cooled last:Inner Outer ring temp = -17.6oCInner Inner ring temp = -16.9oCMax Temp on Module = -11.1oC∆T = 6.5 C across the whole model

1-Feb-12


Alternative, Inner Inner Ring cooling last:Inner Outer ring temp = -16.9oCInner Inner ring temp = -18.2oCMax Temp on Module = -15.1oC∆T = 3.1 C across the whole model

Comparing results with different heat sink temps TIM conductivity at blade ends = 34 W/m-K

Baseline, Inner Outer Ring cooled last:Inner Outer ring temp = -17.6oCInner Inner ring temp = -16.9oCMax Temp on Module = -14.9oC∆T = 2.7 C across the whole model

Module inner radius end temp =

-15.5oC

Module inner radius end temp =

-16.5oC

1-Feb-12


Ring Cooled Last Inner-Outer Ring Inner-Inner RingTemperatures I-O -17.6oC -16.9oC

Temperatures I-I -16.9oC -18.2oC

If TIM at blade ends is 1 W/m-K

Max Temp on Module -11.1oC -11.3oC

∆T of the whole model 6.5oC 6.9o C

∆T across the TIM 3.9oC on IO & 4.1oC on II 3.5oC on IO & 4.9oC on II

Reaction Heat Load to IO 3.85 W (64.2%) 3.42 W (57.0%)

Reaction Heat Load to II 2.15 W (35.8%) 2.58 W (43.0%)

If TIM at blade ends is 34 W/m-K

Max Temp on Module -14.9oC -15.1oC

∆T of the whole model 2.7oC 3.1oC

∆T across the TIM 0.2oC on IO & 0.2oC on II 0.1oC on IO & 0.3oC on II

Reaction Heat Load to IO 3.81 W (63.5%) 2.77 W (46.1%)

Reaction Heat Load to II 2.19 W (36.5%) 3.23 W (53.9%)

Summary on FEA Results on Which Ring is Cooled Last

Inner-Outer Ring cooled last (existing design) in the 4-tubing series connection scheme has a smaller ∆T, but at a slightly warmer module temperature.

1-Feb-12


Backup slides


• 2 blades will be bonded to C-C ring segments with indium and the other 2 with thermally conductive epoxy

• Coating process on parts is being prepared

• Tooling for bonding blades was machined (this was designed for epoxy joints, some adjustments are needed for bonding with indium due to thermal changes)

• Some dummy 2x8 modules with module holders and flex heater were made

• Considering indium as the thermal filler between the tubing and the ring groove

4-Blade Thermal Testing Assembly


These FEA results appear overly optimistic…considering indium as the thermal filler between tubing and ring groove to promote heat transfer into the tube

Study on Heat Transfer of Different Tubing Sizes in C-C Ring Groove

Temp Plot on

Epoxy OnlyTubing OD 1.63 1.82

Groove ID 1.75 1.93

CC Thickness 2.00 2.25

Radial epoxy thickness 0.058 0.056

∆T across 10 mm model 1.66 1.66

∆T across epoxy layer 1.05 1.06

1-Feb-12


A New Plastic Prototype for the HD Outer Assembly - will be used to check fit of tubing with bends and coupling fittings

1-Feb-12


Male nut with M3.5 threads and welded with tubing

Gland welded with tubing

Replaceable aluminum gasket

Female nut with M3.5 threads

CO2 Cooling Coupling Design

1-Feb-12

Front face with knife-edge Front face with knife-edge


CO2 Cooling Coupling Status

Two sets of assemblies were laser-welded• Direct welding was done on gland • Welding rod 312 SS was used for male

thread nut because of larger part tolerance (0.005” vs. 0.002”)

Vacuum leak check was made on both assemblies• No leak on aluminum washer sealing• No leak on gland weld• Leak on the male thread nut weld

Quick conclusion: Design and fabrication method OK, but requires tighter fitting tolerance

Plan: leak on the weldment will be fixed and a pressure test will be conducted before a new round of coupling parts is machined.Will follow Hans suggestion and try vacuum brazing or low-temp soldering (which would remove the need for threaded couplers)

Weld for gland

1-Feb-12

Weld for male threaded fitting

Phase 1 FPix Cooling Loop Design

Documents

Transcript of Phase 1 FPix Cooling Loop Design