Content of Presentation• Low temperature data for magnet-materials (Cu, NbTi,Insulation)
Specific heat, thermal conductivity, resistivity …….
• 4.5K Thermosyphon and 1.9K conduction
• HEPAC Old DOs program calculates: helium properties at different temp and pressures• \\Srv2_div\cryo\TOOLS\CRYODATA\HEPAK3.4
• Computational Fluid Dynamics. https://edms.cern.ch/document/624664/1 .
– MQY study. Heat Conduction through coil with a simple annular heating. (study completed)
– MQY study. Convection of helium through MQY structure. (study in progress)
G.A.Kirby
0
500
1000
1500
2000
2500
3000
3500
0 50 100 150 200 250 300K
kJ/m3
0
20
40
60
80
%
[LEN97] (4-300K) [COL83] (4-20K)
[ELR82] (4-16K) [COL86] (4-18K)
[IWA90] (4-20K) [LAC98] (4-300K)
[HAN77] 0,38Nb+0,62Ti (10-300K) [AND83] (4-300K)
[DUC98] (4-300K) [STA81] (4-300K)
[TIX98] (4-300K) Cp NbTi i (minimum)
Cp NbTi a (maximum) (Cp NbTi a - Cp NbTi i) / Cp NbTi i (%)
Cp NbTi (kJ/m3.K)
Cp NbTi (B,T) in J/m3.K
T < 20 K TcB= 9.2 * (1 - B / 14.5) ^ 0.59 If T < TcB Then Cp = 49.1 * T ^ 3 + 64 * B * T Else Cp= 16.4 * T ^ 3 + 928 * T
T < 50 K Cp = -0.217724 * T ^ 4 + 11.983792 * T ^ 3 + 553.712993 * T ^ 2 - 7846.120813 * T + 41382.928569
T < 175 K Cp = -0.00000000482 * T ^ 4 + 0.00000297583 * T ^ 3 - 0.00071625148 * T ^ 2 + 0.08302230116 * T - 1.53178 * 10^6
T < 500 K Cp = -0.0000000000629 * T ^ 4 + 0.0000000929657 * T ^ 3 - 0.0000516653121 * T ^ 2 + 0.0137062419692 * T + 1.23554 * 10^6
T < 1000 K Cp = -0.000000257 * T ^ 2 + 0.000955466 * T + 2.450087571 * 10^6
** Hunt for data **Materials
NbTi
Cupper
Kapton
Epoxy
Stainless Steel
Iron
Cryogenic Material Properties
Cp
Resistivity
Conductivity
……..
HeliumTCpMQ ..HeliumTCp
QM
.
gVBuoyancy KK .. 5.48.4
22
hh A
M
D
fP
0.01
0.10
1.00
1.E+02 1.E+03 1.E+04 1.E+05Reynolds number Re
Fric
tion
fact
or
f He 300KwaterHe 40 - 70KHe 4.5KSimonsonHoenigKraftFit
716.04.08.0 PrRe259.0
b
wNu
h
h
D
A
MRe
Cp of Helium at 1.67 and 1.0 Bar
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
0 1 2 3 4 5 6
Tem p [K]
Cp
[J/
kg-K
]
Cp He 1.67 Bar
Cp He 1 Bar
f
PDAM hh 2
1200
3LqT
Heat Extraction through Pipe with fixed 0.1K dT 1.85 to 1.95K Helium
0.05.0
10.015.020.025.030.035.040.0
0 0.1 0.2 0.3 0.4 0.5 0.6
Pipe Diameter (m)
Pip
e M
ax L
eng
th (
m)
L(m) 500W
L(m) 1kW
Van Sciver, “Helium Cryogenics”, pp. 143 - 144
>10^5 its turbulent
4.5K thermosyphon and 1.9K conduction
HePAC
Old Dos Program that give Helium many properties.
BUT needed updating to new system before Dos disappears or changes !
\\Srv2_div\cryo\TOOLS\CRYODATA\HEPAK3.4
HEPAK is a computer program for calculating the thermophysical properties of helium from fundamental state equations. The state equations are valid from 0.8 Kelvin or the melting line to 1500 Kelvin, including the superfluid range, the lambda line, and liquid vapor mixtures; as a function of pressure they are valid up to 1000 bars, except between 80 and 300 Kelvin where they are valid to 20,000 bars. HEPAK also includes thermal transport properties in both normal and superfluid, the dielectric constant, refractive index, and fluid surface tension. The user of HEPAK and this manual should be familiar with thermophysical concepts as applied to fluid properties
Cp of Helium at 1.67 and 1.0 Bar
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
0 1 2 3 4 5 6
Temp [K]
Cp
[J/
kg-K
]
Cp He 1.67 Bar
Cp He 1 Bar
Computational Fluid Dynamics
Computational Fluid Dynamics (CFD) is an analysis of fluid flow, heat transfer and associated phenomena in physical systems using numerical methods.
The basis of computational fluid dynamics is the reduction of the continuum differential equations describing the dynamics of the fluid (Navier-Stokes + mass and energy conservation equations) into a system of algebraic equations at a finite number of "grid" points, and the solving of the equations at these limited number of points only.
TS/CV/Detector Cooling - CFD Team
A wide range of application fieldsAerospace
Automotive
Biomedical
Buildings
Chemical
Environment
Marine
Power gen.
Turbo-machinery
MQY study. Heat Conduction through coil with a simple annular heating at
inner radii.
Steel
NbTi
Kapton
Fiberglass Epoxy
Cu
4.2 K
Heat source
Conduction heat distribution results
Heating 50 mW/mm^3 Into 2mm annulus
Heating 100 mW/cm^3 Into 2mm annulus
6.9 K5.7 K
Heat load
Convection heat transfer through MQY at 4.5K
Future tests
Quench heaters
The end