Pixel cooling specifications Kurt Gabathuler June 13, 2004 Pixel cooling specifications

For good pressure regime: inlet via top, outlet via bottom Pixel Coolant Paths For good pressure regime: inlet via top, outlet via bottom + z - z Pixel Cooling Rack Pixel Cooling Rack Left half barrel + z  - z: 124 m 5 circuits Right half barrel - z  + z: 114 m 5 circuits Disks at + z: 109 m 4 circuits Disks at - z: 127 m 4 circuits Total 18 circuits

Pixel cooling rack

left half barrel right half barrel disks +z disks -z Heat exchanger filters tank Circulation pump

CMS Pixel Detectors and service structures inside the tracker -z 3 half-disks attached to service structure flexible connections barrel service half-cylinder half-barrel optohybrids & control electronics +z

Pixel Half Barrel 3 layers group of 4 tubes trapezoidal Al tube with dhydr=3mm 0.3mm wall thickness

Cooling channels Optohybrids

Frontview of half-barrel Gap between barrel & service tube

One of 10 Pixel Barrel Cooling circuits +/- z -/+ z 32 cc/s T T+2.0 32 cc/s 63 cc/s 63 cc/s 56.4 cc/s service tube service tube 47.75 cc/s 31 cc/s T T+1.6 31 cc/s

Cooling of quarter disk, Forward Pixel Alu 2.5mm x 6 mm, dhydr=3.5mm IN OUT

One of 8 forward Pixel Cooling Circuit Supply 10mm id Service Tube 4mm id ¼ disks 6 blades disk 1 disk 2 disk 3 15cc/s T=1.80 45cc/s 15cc/s 15cc/s Total pressure drop ~ 2000 mbar

Summary Pixel Cooling Circuits (full pixel configuration 3 barrel layers and 23 disks) Number of circuits Length per circuit [m] Flow per circuit [cc/s] Load per circuit [W] Coolant T [0K] pressure drop [bar] Barrel +z-z 5 124 63 560 5.1 2.0 Barrel -z+z 114 540 4.9 Disks +z 4 109 45 345 4.3 Disks -z 127 365 4.4 Total 18 990 8340

Additional slides

pressure transducer p  3.5 bar abs. Bypass pressure transducer p  3.5 bar abs. heat exchanger T T gas inlet to blow coolant into reservoir Reservoir pump: p  1.7 bar @ 1 liter / s X Disks +z Total flow 60, 120 or 180 cc/s (1, 2, or 3 disks) X X X X P F PT X X X P,T X X X Disks -z Total flow 60, 120 or 180 cc/s (1, 2, or 3 disks) X X X X P F PT X X X P,T X X manual pressure adjustment flowmeters or p(in/out) manual valves X Barrel +z-z Total flow 160 or 320 cc/s (layers 1+2 or 3 layers) X X X P X X X X F PT P,T X X X X X X Barrel -z+z Total flow 160 or 320 cc/s (layers 1+2 or 3 layers) X X P X X X X F PT P,T X X X X

Barrel+z in high, -z out low pressures in abs bar, dyn, static 0.69 0.92 path length 92.5 m 12 1. 21 1.55 1.36 2.22 10 1.02 2. 22 12 1.71 2.22 5.2 10 1.52 2.88 3.20 1.50 3.20 12 p1.70, 0 external pressure pabs 3.20, 3.20

Barrel-z in high, +z out low pressures in abs bar, dyn, static 1.30 1.55 1.25 1.55 12 path length 80.5 m 1.40 2.22 10 1.06 2. 22 12 1.75 2.22 5.2 10 1.56 2.88 3.20 1.61 3.20 12 p1.59, 0 external pressure pabs 3.20, 3.20

Disks+z in high, +z out low pressures in abs bar, dyn, static 1.11 1.22 path length 84.3 m 12 1.69 1.85 1.62 2.52 10 0.97 2. 52 12 2.28 2.52 5.2 10 1.56 3.18 3.50 1.76 3.50 12 p1.74, 0 external pressure pabs 3.20, 3.20

Disks-z in high, -z out low pressures in abs bar, dyn, static 1.73 1.85 1.71 1.85 12 path length 87.5 m 1.64 2.52 10 0.99 2. 52 12 2.30 2.52 5.2 10 1.58 3.18 3.50 1.74 3.50 12 p1.76, 0 external pressure pabs 3.20, 3.20

  Measurement of flow through the individual cooling pipes of pixel barrel  

Coolant Flow Distribution (C6F14 at room temperature) 2 3 4 5 35 cc/s (measured) 35 cc/s (measured) 1 2 3 4 5  12 % variation  9 % variation

re drops for staged pixel Pressu re drops for staged pixel layer 1 or 2 Pixel detector configuration Number of circuits in operation Nominal flow per circuit [cc/sec] Total pressure Drop [bar] Pressure drop in supply/return line [bar] in detector Barrel layers 1+2 10 31/32 1.00 2 ´ 0.15 0.70 Barrel layers 1+ 2+3 63 1.70 0.50 BARREL COOLING CIRCUIT layer 3 DISK ¼ disks COOLING disk 1 disk 2 disk 3 6 blades CIRCUIT 2 ´ 1 Disk 8 15 1.35 0.05 1.25 2 Disks 30 1.55 0.15 3 Disks 45 1.75 0.25

Summary Pixel Cooling Circuits Flow per circuit [cc/s] (possible initial pixel configuration barrel layers 1 + 2 and 2  2 disks) Number of circuits Length per circuit [m] Flow per circuit [cc/s] Load per circuit [W] Coolant T [0K] pressure drop [bar] Barrel +z-z 5 92.5 31.5 252 4.5 1.00 Barrel -z+z 80.5 0.89 Disks +z 4 84.3 30 204 3.8 1.54 Disks -z 87.5 1.56 Total 18 555 4152