PAX DETECTOR THERMAL SIMULATION FzJuelich 27102008 Vittore Carassiti

PAX DETECTOR THERMAL SIMULATION Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 1

PAX DETECTOR FEM* ASSEMBLY LAYOUT ELECTRONIC SUPPORT TARGET CELL HEAT FLUX COOLING PLATE COOLING TUBE SILICON SUPPORT SILICON DETECTOR VACUUM CHAMBER * FEM = Finite Element Modeler Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 2

MATERIALS PARTS MATERIALS PART MATERIAL SILICON DETECTOR SILICON TARGET CELL ALUMINUM SILICON SUPPORT ALUMINUM ELECTRONIC SUPPORT ALUMINUM VACUUM CHAMBER STAINLESS STEEL MATERIAL PROPERTIES MATERIAL DENSITY (Kg/m^3) THERMAL CONDUCTIVITY (W/m. K) EMISSIVITY (*) SPECIFIC HEAT (J/Kg. K) ALUMINUM 2700 237 0. 09 900 STAINLESS STEEL 7960 16, 3 0, 16 502 SILICON 2340 115 0, 9 703 (*) From the Engineering Toolbox (www. engineeringtoolbox. com) Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 3

THE ANALISYS THE FOLLOWING ANALISYS HAVE BEEN PERFORMED : RADIATION ANALISYS SIMULATION EVALUATING THE AMOUNT OF HEAT LOAD COMING FROM RADIATION TEMPERATURE ANALISYS SIMULATION EVALUATING THE DETECTOR’S TEMPERATURE DISTRIBUTION COMING FROM ELECTRONIC POWER AND RADIATION Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 4

RADIATION ANALISYS q SILICON SUPPORT SET AT CONSTANT TEMPERATURE q ELCTRONIC POWER SWITCHED OFF q VACUUM CHAMBER SET AT CONSTANT TEMPERATURE SILICON SUPPORT VACUUM CHAMBER Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 5

RADIATION ANALYSIS BOUNDARY CONDITIONS FEM RADIATION ANALYSIS BCs SILICON DETECTOR SILICON SUPPORT RADIATIVE THERMAL COUPLINGS TO ALL PARTS CONDUCTIVE THERMAL COUPLINGS TO SILICON SUPPORT CONSTANT TEMPERATURES (C°) COOLING TUBE TARGET CELL ELECTRONIC & SUPPORT TO ALL PARTS VACUUM CHAMBER TO ALL PARTS -20 20 ; 40 ; 60 HEAT LOAD (W) SWITCHED OFF ADDITIONAL INFORMATIONS § - SHADOWING CHECKS BETWEEN PARTS PERMORMED Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 6

RADIATION ANALYSIS RESULTS 2° ANALISYS - SHARED POWER % 76. 01 80. 00 70. 00 BOUNDARY CONDITIONS SILICON SUPPORT SURFACES CONSTANT TEMP (C°) VACUUM CHAMBER WALLS CONSTANT TEMP (C°) 60. 00 1° Analysis -20 20 40. 00 2° Analysis -20 40 30. 00 3° Analysis -20 60 VACUUM CHAMBER 50. 00 SILICON DETECTOR TARGET CELL 23. 90 20. 00 0. 11 10. 00 RADIATION ANALYSIS RESULTS PART SILICON DETECTOR 1° ANALYSIS VACUUM CHAMBER Fz-Juelich , 27/10/2008 3° ANALYSIS AVERAGE TEMP (C°) POWER (W) -18, 3 -22, 47 -17, 6 -21, 81 -16, 7 -21, 00 63, 68 SILICON SUPPORT TARGET CELL 2° ANALYSIS -17 -0, 104 91, 27 -15, 5 -41, 10 Vittore Carassiti - INFN FE -0. 096 -69, 37 124, 7 -13, 5 -0. 085 -103, 6 7

TEMPERATURE ANALISYS q COOLING TUBE WALL SET AT CONSTANT TEMPERATURE q ELCTRONIC POWER SWITCHED ON COOLING TUBE Fz-Juelich , 27/10/2008 ELECTRONIC POWER Vittore Carassiti - INFN FE 8

TEMPERATURE ANALYSIS BOUNDARY CONDITIONS FEM TEMPERATURE ANALYSIS BCs SILICON DETECTOR SILICON SUPPORT RADIATIVE THERMAL COUPLINGS TO ALL PARTS CONDUCTIVE THERMAL COUPLINGS TO SILICON SUPPORT CONSTANT TEMPERATURES (C°) COOLING TUBE TARGET CELL ELECTRONIC & SUPPORT VACUUM CHAMBER TO ALL PARTS VACUUM CHAMBER & SILICON SUPPORT TO ALL PARTS TO SILICON SUPPORT -20 HEAT LOAD (W) 85 ADDITIONAL INFORMATIONS § - SHADOWING CHECKS BETWEEN PARTS PERMORMED § - ENVIRONMENT TEMPERATURE = 25 C° Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 9

TEMPERATURE ANALYSIS RESULTS 69. 20 SHARED POWER % 70. 00 BOUNDARY CONDITIONS 60. 00 ENVIRONMENT TEMPERATURE = 25 C° COOLING TUBE WALL TEMP (C°) 50. 00 40. 00 ELECTRONIC HEAT LOAD (W) ELECTRONIC SILICON DETECTOR 26. 40 SILICON SUPPORT 30. 00 -20 TARGET CELL 20. 00 85 3. 30 10. 00 1. 20 0. 00 ANALYSIS RESULTS PART TEMPERATURE (C°) POWER (W) Tmin Tmax SILICON DETECTOR -19, 5 -12, 8 -32, 4 SILICON SUPPORT -20 -16, 6 -4 -11, 9 -11, 7 -1, 5 -20 117, 2 TARGET CELL COOLING TUBE WALL -85, 00 ELECTRONIC VACUUM CHAMBER Fz-Juelich , 27/10/2008 28 Vittore Carassiti - INFN FE 31 5, 7 10

SILICON SUPPORT – TEMPERATURE DISTRIBUTION Tmin = -20 C° ; Tmax = -16, 6 C° Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 11

SILICON DETECTOR – TEMPERATURE DISTRIBUTION Tmin = -19, 5 C° ; Tmax = -12, 8 C° Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 12

TARGET CELL – TEMPERATURE DISTRIBUTION Tmin = -11, 9 C° ; Tmax = -11, 7 C° Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 13

DETECTOR ASSEMBLY – TEMPERATURE DISTRIBUTION Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 14

COOLING DESIGN TOTAL COOLING POWER (4/4) Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 15

COOLING DESIGN COOLING FLUID TEMPERATURE VS CONVECTION COEFFICIENT T (C°) fuid temperature @ Twall = -20 C° & Dtube = 8 mm 0. 00 E+00 -2. 00 E+01 -4. 00 E+01 -6. 00 E+01 Tfluid -8. 00 E+01 Tdelivery -1. 00 E+02 -1. 20 E+02 -1. 40 E+02 -1. 60 E+02 25 50 75 100 125 150 175 200 225 250 275 300 COOLING FLUID & CONVECTION COEFFICIENT SELECTION α (W/m^2 COOLING FLUID : ETHANOL ALCOHOOL °C Boiling point 78, 5 Density (Kg/m^3) ρ 832 Freezing point -114 Specific heat (J/Kg. K) Cp 2215 Thermal conductivity (W/m. K) λ 0, 13 Kinematic viscosity (m^2/s) ν 3, 23 E-06 Kinematic viscosity @ Tw (m^2/s) νw 2, 88 E-06 Convection coefficient α Delivery temperature Td -41 Wall temperature Tw -20 Fluid temperature Tf = (Td + Tw)/2 -30, 5 Fz-Juelich , 27/10/2008 W/m^2 C° 170 ETHANOL PROPERTIES @ Tf and atmospheric pressure Vittore Carassiti - INFN FE 16

COOLING DESIGN FLOW SPEED, FLOW RATE AND PRESSURE LOSS 40. 00 20. 00 25 50 75 100 125 150 175 200 225 250 275 300 α (W/m^2 C°) -20. 00 -40. 00 -60. 00 -80. 00 -100. 00 -120. 00 flow rate (Kg/h) flow speed (m/min) -140. 00 Tfluid (C°) d=8 Tdelivery (C°) d=8 -160. 00 Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 17

CONCLUSIONS A THERMAL ANALISYS INVESTIGATING THE RADIATION EFFECTS ON THE SILICON DETECTOR HAS BEEN DONE. A SUPPLEMENTARY ANALISYS CONSIDERING BOTH THE ELECTRONIC POWER AND THE RADIATION HAS BEEN ALSO SIMULATED. AN IMPROVEMENT OF THE ANALISYS RESULTS CAN BE ACHIEVED , GIVEN THE FOLLOWING INFORMATIONS : Ø AVERAGE WORKING TEMPERATURE OF THE SILICON DETECTOR Ø VALUE OF THE ELECTRONIC POWER Fz-Juelich , 27/10/2008 Vittore Carassiti - INFN FE 18