ATLAS muon chambersheat transfer efficient
description
RFNC – VNIITFSUE «Strela» Snezhinsk, 2003
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.