ATLAS muon chambersheat transfer efficient

description

RFNC – VNIITFSUE «Strela» Snezhinsk, 2003

t.v.lebedeva@vniitf.ru

Contents

Basic problems Approaches to designing simplified

thermal models for muon chambers Simplified thermal models 1 and 2 Chambers as homogeneous objects to

simulate heat transfer across them Multilayers and End plugs as

homogeneous components to simulate heat transfer along chambers

MDT tubes heating of BIS chambers

Basic problems to be solved

Simplified thermal models for typical muon chambers

Heat transfer across chambers Heat transfer along chambers Free-convection heat exchange inside

the fragments of ATLAS facility for the most heat loaded chambers

Air flow blocking between the MDT chambers

The chambers under consideration

BIS, BIL without RPC;

BMS, BML with RPC on both sides of the chamber;

BOL, BOS with RPC on one side of the chamber

General scheme of chamber

Studied problems

Heat transfer across chambers to evaluate temperature gradients between outer surfaces of the multilayers

Heat transfer along the BIS chambers with the source in Faraday Cage (FC)

Approaches to design simplified thermal models

From simple to complex Actual structure is divided into fragments

to enable direct simulation of heat transfer Fragment is replaced with homogeneous

material having parameters equivalent to those of the initial fragment

Set of fragments is replaced with homogeneous material

Simplified thermal model (Model 1)

for BМS, BМL chambers

hMultilayer

hProtection

hRPC

hSpaser

hGap

hSpaserH H

1

2

1

Y

Z

hMultilayer

hProtection

hRPC

hSpaser

hGap

hSpaserH H

1

2

1

Y

Z

Y

Z

Simplified thermal model (Model 1)

for BOS, BOL chambers

hMultilayer

hProtection

hRPC

hSpaser

hGap

hSpaserH H

1

2

3

Simplified thermal model (Model 1)

for BIS chamber

hMultilayer

hProtection

H

H

1

hSpaser

Y

Z

hMultilayer

hProtection

H

H

1

hSpaser

Y

Z

Y

Z

Simplified thermal model (Model 1)

for BIL chamber

hMultilayer

hSpaser hSpaserH H

1

2

1

hProtection

Y

Z

Y

Z

Materials of simplified thermal models

1, 3-have specific thermal characteristics and replace the layers of aluminum tubes, RPC, gas-filled gaps, and heat-isolation

2-corresponds to "air" and cross plates.

Heat transfer in the material 2 is caused by heat conduction, convection and radiation

Simplified thermal models for 2D calculations based on Model 1

hSpaserH

1

2

1Y

H1

H1

L

E1E2

E2

RO

HV

d d

X

E3

E3

d

d

E1

hSpaserH

1

2

3

Y

H1

H2

L

E4

E2

RO

HV

d d

X

E3

dE1

hSpaserH

1

2

3

Y

H1

H1

L

E1

RO

HV

d

X

E1

H

1

L

E1RO

HV

Y

X

d

The highlighted areas are the heat sources

Heat sources

RPC releases heat along the perimeter of structure equal to 0.07W/4cm (1.75W/m)

Power/mezz board for all types of chambers 1.62 W

 

Thermal model 2

Structure elements treated separately

RPC Air gaps and heat-shielding (space

between RPC and multilayer) Multilayer, Faraday cage, End plug Space between multilayers (Air + Cross

plates)

Model 2. BML, BMS chambers

E1

E3

E3

Air + crossplateSupport +crossplate

Support +crossplate

Protection + air

RPC

L

RO

HV

hRPC

hGap+ hProtection

hMultilayer

hSpacer

H

E1

E2

E2

E2

d

FCEndplug FC

Endplug

MultilayerY

XL1 L2

FCEndplug FC

Endplug

Multilayer

Protection + air

RPC

E2d

Model 2. BOL, BOS chambers

E1

E3

Air + crossplateSupport +crossplate

Support +crossplate

Protection

L

ROHV

hRPC

hGap+ hProtection

hMultilayer

hSpacer

H

E1

E2

FCEndplug FC

Endplug

Multilayer

FCEndplug FC

Endplug

Multilayer

Protection + air

RPC

E2

L1 L2

Y

X

d

hProtection

Model 2. BIL chamber

E1

Air + crossplateSupport +crossplate

Support +crossplate

Protection

L

ROHV

hProtection

hMultilayer

hSpacer

H

E1FC

Endplug FC

Endplug

Multilayer

FCEndplug FC

Endplug

Multilayer

Protection

L1 L2

Y

X

d

Model 2. BIS chamber

HV

H

L1 L2

L

Protection

Protection

RO

hProtection

E1

FCEndplug

FCEndplug

Multilayers 1,2 + Spacer

X

Y

2hM

ultil

ayer

+ h S

pace

r

d

CHAMBERS AS EFFICIENT HOMOGENEOUS OBJECTS

TO SIMULATE HEAT

TRANSFER ACROSS

THE CHAMBERS

Multilayer of tubes presented as

homogeneous object

8 2 . 0 2 2

3 0 . 0 3 5

2 9 . 2

1 5

2 6 . 0 1 1

A l u m a n

g a s

a i r

g l u e0 . 0 3 5 , 0 . 0 1 7 5

2l

Y

Z

Y

Z

2 6 . 0 1 1

1 0 8 . 0 3

3 0 . 0 3 5

2 9 . 2 A l u m a n

g a s

a i r

g l u e

Y

Z

Y

Z

1 5

2 6 . 0 1 1

2 6 . 0 1 1

2 6 . 0 1 1

0 . 0 3 5 , 0 . 0 1 7 5

2l

2D problems in YZ plane Left and right sides are

adiabatic walls Temperature values are given

(T2>T1)on the bottom and upper surfaces

Heat transfer in gas and in air is caused by heat conduction and convection

Radiative heat transfer is not taken into account

Direction of gravity force is varied

Y

Z

Y

Z

1T

2T

0q 0q

Presentation of multilayers as homogeneous objects

Convection inside the tubes has almost no effect on transverse heat transfer for temperature gradients studied

Estimated efficient thermal conductivity across multilayers For 3-layers set: æeff =2.00W/(mK) For 4-layers set: æeff =1.76W/(mK)

The effecient heat conductivity for the air gap between multilayers

depends on the chamber orientation

Each muon chamber has its own component of vector g

g

hspacer

L

y

x

T1

T2

q=0 q=0air hspacer

L

y

x

T1

T2

q=0 q=0hspacer

L

y

x

y

x

T1

T2

q=0 q=0air hspacer

L

y

x

T1

T2

q=0 q=0air hspacer

L

y

x

T1

T2

q=0 q=0hspacer

L

y

x

y

x

T1

T2

q=0 q=0air

Components of gravity g

Chamber xg yg

01 -9.81 0

02 -9.063 -3.754

03 -6.9367 -6.9367

04 -3.754 -9.063

05 0 -9.81

06 3.754 -9.063

07 6.9367 -6.9367

08 9.063 -3.754

09 9.81 0

10 9.063 3.754

11 6.9367 6.9367

12 3.754 9.063

13 0 9.81

14 -3.754 9.063

15 -6.9367 6.9367

16 -9.063 3.754

The effective heat conductivity for air gap between multilayers

Heat transfer between multilayers is

caused by heat conductivity convection radiation

. .cond conv radiationeff eff eff

æ æ æ radiationeff

Tq

h

æ

Heat transfer due to heat conduction and convection

hspacer

L

y

x

T1

T2

q=0 q=0air hspacer

L

y

x

T1

T2

q=0 q=0hspacer

L

y

x

y

x

T1

T2

q=0 q=0air

. . spacercond conveff

q h

T

æT2=290.1, 290.2, 290.5, 291, 292

T1=290

. .cond conveff T æ 0.2 1/3

Simulated values (markers) of efficient heat conductivity and analytical curves for

BIL and BML chambers

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.20.00

0.05

0.10

0.15

0.20

0.25

0.30

Th

erm

al c

on

du

ctiv

ity W

/(m

0 K)

T

BIL01 BIL03 BIL05 BIL15

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.20.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.55

0.60

0.65

0.70

Th

erm

al c

on

du

ctiv

ity W

/(m

0 K)

T

BML01 BML03 BML05 BML15

Simulated values (markers) of efficient heat conductivity and analytical curves for

BMS and BOL chambers

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.20.00

0.05

0.10

0.15

0.20

0.25

0.30

The

rma

l con

duct

ivity

W/(

m0 K

)

T

BMS02 BMS04 BMS14 BMS16

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.20.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.55

Th

erm

al c

ond

uctiv

ity W

/(m

0 K)

T

BOL01 BOL03 BOL05 BOL15

Simulated values (markers) of efficient heat conductivity and analytical curves for

BOS chambers

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.20.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.55

0.60

0.65

Th

erm

al c

on

du

ctiv

ity W

/(m

0 K)

T

BOS02 BOS04 BOS14 BOS16

Velocity field for chamber BIL01

Velocity field for chamber BIL05

Velocity field for chamber BMS04

Velocity field for chamber BOS04

Velocity field for chamber BOL05

Velocity field for chamber BML05

Cross-plates influence on heat transfer between the mulilayers

hspacer hcross plate

hglue=0.75mm

6mm

Al

glue

L

hspacer

3mmcross plate+glue

X

Yair

T1

T2

L

hspacer

3mmcross plate+glue

X

Yair

T1

T2

BIL:BMS:BML:BOS:BOL:

. .0.083 0.9953 cond conveff

æ æ. .0.072 0.996 cond conv

eff æ æ

. .0.103 0.9965 cond conveff

æ æ. .0.097 0.99676 cond conv

eff æ æ

. .0.073 0.9975 cond conveff

æ ææeff (cond.+conv.+cross_plate) =+ æeff(cond.+conv.)

Heat transfer by radiation

4 41 2

1 2

1 11

T Tq

Radiative heat transfer between the multilayers treated as heat exchange between two parallel planes and described by

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.90

1

2

3

4

5

6

7

8

q

[W/m

2 ]

4 4 31 2

1 2

41 1 2

1

T T T Tq

34

2radiationeff

h T

æ

This technology is applied to calculate the value of efficient heat conductivity for specific chamber by means of Selection of parameters , Estimation of average temperatures at the internal surfaces of the multilayers (values of T1, T2) Selection of , corresponded to chosen chamber And on a final stage estimation of the value of heat conductivity with the help of above expression

Calculations of the effective coefficient of heat conductivity for

air gap between multilayers

. . _

3. . 4

.2

spacer cond conv cross plate radiationeff eff eff

cond conv radiationeff eff

h TT

æ æ æ

æ æ

Presenting RPC as homogeneous objects

0,3(Al) 12,9(Бумага пористая) 0,3(Al) 3,3

6,64 0,19 (PET)

21(воздух)

1

2

1

2

1

1

1

2

3,3

3,3

3,3

6,64

0,3(Al)

0,3(Al)

0,3(Al)

0,3(Al)

0,3(Al)

0,3(Al)

0,19 (PET)

9,4 (Бумага пористая)

54,4(Бумага пористая)

14,4(Бумага пористая)

0,19 (PET)

0,19 (PET)

0,19 (PET) 0,017(Cu)

3(Пена стериновая) 0,012 (Клей)

0,2(Бумага)

0,2(Бумага)

0,08 (Клей)

0,05 (Клей)

0,05 (Клей)

0,08 (Клей)

1,8 (Бакелит)

1,8 (Бакелит)

0,017(Cu) 0,19 (PET) 0,012 (Клей)

2 (97%С2Н2F4+3%C4H10)

For BOS, BMS,BML æeff=0.0291W/(mK) For BOL æeff=0.0288W/(mK)

Simplified heat models of the BIS chambers

3

4

4

5

1

2

2

1

3

A

B D

С

3

4

4

5

1

2

2

1

3

A

B D

С

Material

ρ C æ

1 94 1195 0.0265

2 129 938 1.76

3 242 950 0.054

4 133 983 0.1135

5 126 983 0.11

Simplified thermal models of the BIL chambers

4

3

4

1

3

1

2

2

СA

DB

4

3

4

1

3

1

2

2

СA

DB

Material

Ρ C æ

1 150

1110

0.027

2 129

938 1.76

3 13 9900.083+0.9953|T|δ+0.17٠4εσ T3 /(2- ε)

4 131

962 0.2

Simplified thermal models of the BMS and BML chambers

22

33

44

11

11

22

33

44 44

55

33

33

55

66

66

B

AС

D

Material

æ for BMS æ for BML

1 0.028 0.028

2 0.027 0.027

3 2.00 2.00

40.072+0.996 |T|δ +0.17٠4εσT3/(2- ε)

0.103+0.9965 |T|δ +0.317٠4εσT3/(2- ε)

5 0.0279 0.0279

6 0.043 0.044

Simplified thermal models of the BOS and BOL chambers

22

33

44

11

22

33

44 44

11

55

55

66

55

B

AС

D

Material æ for BOS æ for BOL

1 0.028 0.028

2 0.027 0.027

3 2.00 2.00

40.097+0.9967|T|δ +0.317٠4εσT3/(2- ε)

0.073+0.9975 |T|δ +0.317٠4εσT3/(2- ε)

5 0.163 0.163

6 0.044 0.044

Temperature gradients across chambers for BIS, BIL

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

1,0 BIS

(TA-T

B),

0 K

(TС-TD),0K

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

1,0 BIS

(TA-T

B),

0 K

(TС-TD),0K

0 2 4 6 8 100

1

2

3

4

5

BIL 01,09

BIL 03,07

BIL 05

BIL 11,15

BIL 13

(TA-T

B),

0 K(TС-TD),

0K

0 2 4 6 8 100

1

2

3

4

5

BIL 01,09

BIL 03,07

BIL 05

BIL 11,15

BIL 13

(TA-T

B),

0 K(TС-TD),

0K

Temperature gradients across the chambers BMS,

BML

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

1,0

1,2

1,4BML 01,09

BML 03,07

BML 05

BML 11,15

BML 13

(TС-TD),0K

(TA-T

B),

0 K0 2 4 6 8 10

0,0

0,2

0,4

0,6

0,8

1,0

1,2

1,4BML 01,09

BML 03,07

BML 05

BML 11,15

BML 13

(TС-TD),0K

(TA-T

B),

0 K

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

BMS 02,08

BMS 04,06

BMS 12,14

BMS 10,16

(TС-TD),0K

(TA-T

B),

0 K

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

BMS 02,08

BMS 04,06

BMS 12,14

BMS 10,16

(TС-TD),0K

(TA-T

B),

0 K

Temperature gradients across chambers BOS and

BOL

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

1,0

1,2

1,4

1,6

1,8

2,0

2,2

2,4

BOL 01,09

BOL 03,07

BOL 05

BOL 11,15

BOL 13

(TС-TD),0K

(TA-T

B),

0 K

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

1,0

1,2

1,4

1,6

1,8

2,0

2,2

2,4

BOL 01,09

BOL 03,07

BOL 05

BOL 11,15

BOL 13

(TС-TD),0K

(TA-T

B),

0 K

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

1,0

1,2

1,4

BOS 02,08

BOS 04,06

BOS 12,14

BOS 10,16

(TС-TD),0K

(TA-T

B),

0 K

0 2 4 6 8 100,0

0,2

0,4

0,6

0,8

1,0

1,2

1,4

BOS 02,08

BOS 04,06

BOS 12,14

BOS 10,16

(TС-TD),0K

(TA-T

B),

0 K

MULTILAYER AND END PLUGS AS HOMOGENEOUS OBJECTS

TO SIMULATE

HEAT CONDUCTION

ALONG CHAMBERS

Single MDT-tube presented as a homogeneous cylinder

29.2

30.0

Lgas

Al

Y

Z

Y

Z

Y

X

Y

X

1T 2T

Dependence of æeff on tube length, chamber position and temperature

gradients

1 2 3 4 5 6 7 8 96.2

6.3

6.4

6.5

6.6

6.7

6.8

6.9

7.0

Th

erm

al c

on

du

ctiv

ity W

/(m

0 K)

Chambers

L=150, =2 L=150, =0.5 L=300, =2 L=300, =0.5

æeff=6.32W/(mK)

Presenting a set of MDT-tubes as homogeneous

object

108.03

30.035

L«tube»air

Y

Z

Y

Z

15

26.011

26.011

26.011

Y

X

Y

X

82.022

30.035

15

26.011

air

Y

Z

26.011

«tube»L

Y

X

82.022

30.035

15

26.011

air

Y

Z

Y

Z

26.011

«tube»L

Y

X

Y

X

Fragment of multilayer consisted of 4 monolayers

æ=5.44W/(mK)

Tube block

Fragment of multilayer consisted of 3 monolayers

æ=5.51W/(mK)

End Plug

Ring

Central insert

Plastic isolator

Simplified model of End Plug for simulations

-5 0 5 10 15 20 25 30 35 40 45 50 55

0

5

10

15

20

25

Central insert

Signal cap Gasjamper

Plastic isolator

Ring

43.7

R

0 2 11.212.5

15.5 20.7 25.7 27.7 38.7 46.2 50.9

R=4.1

R=8

R=2.5 R=1.4R=4

R=11.14

R=15.00R=14.6

X

Simplified model of End Plug with indicated materials for calculations

0 10 20 30 40 50

0

5

10

15

20

25

CuZn39Pb2

Noryl

Al

43.7

R

0 2 11.212.5

15.5 25.7 27.7 38.7 46.2 50.9

R=4.1

R=8

R=2.5 R=1.4R=4

R=11.14

R=15.00R=14.60

X

Simplified model for End Plug

-5 0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 5 0 5 5

0

5

1 0

1 5

2 0

2 5

L

K G

DF

E

B

A

2 6 . 7

4 3 . 70 2 1 1 . 21 2 . 5

1 5 .5 2 5 . 7 2 7 . 7 4 6 . 2 5 0 . 9

R = 4 .1

R = 8

R = 2 . 5 R = 1 . 4R = 4

R = 1 1 . 1 4

R = 1 5 . 0 0R = 1 4 .6

Р и с . 4 . 8 . У п р о щ е н н а я м о д е л ь E n d P l u g д л я т р е х м е р н о г о м о д е л и р о в а н и я

- 5 0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 5 0 5 5

0

5

1 0

1 5

2 0

2 5

2 6 . 7

0

1 2 . 5

5 0 . 9

R = 4 . 1

R = 1 5 . 0 0

1

2

3

Р и с . 4 . 9 . П р о т о т и п E n d P l u g д л я т р е х м е р н о г о м о д е л и р о в а н и я

G r o u n d p l a t e

HEATING OF MDT TUBES FOR THE BIS CHAMBER

2D model of a BIS chamber

Ventilation of ATLAS cavernAir velocity around the muon

chambers

Airflow around chambers BIS16 (left), BIS10 (right)

Temperature fields in the Faraday Cage of BIS chamber, located in the air

cavern

Problem statement Inlet KB – 0.03 m/c Inlet AB– 0.06 m/c Outlet DE (0.13m length) 100% of flow Boundaries – adiabatic walls Energy source 5.0676E4 [W/m3]

Velocity field for Faraday Cage RO (BIS10)

Velocity fields for two regions of Faraday Cage RO (BIS10)

Temperature fields for two regions of Faraday Cage RO

(BIS10)

Temperature field for fragment of BIS10

Fragments of BIS10 chamber

Temperature in the lower multilayer of tubes

Temperature in the upper multilayer of tubes

Fragment of velocity field around of BIS16 chamber

Temperature field for BIS16 chamber

Fragment of velocity field for chamber BIS16

Temperature distribution for chamber BIS16

Faraday Cage, BIS16 chamber

Velocity in the left sub-domain of Faraday Cage

Velocity in the right sub-domain of Faraday Cage

Conclusion

Two type of simplified thermal models were created to be used in the global simulations

Simplified thermal models were developed to describe heat transfer across the chambers

Heat release in Faraday Cage was simulated and results were applied to describe heat transfer along the BIS chambers.