# Presentation: 352593

## Pixel cooling specifications

_**Pixel cooling specifications**_

- Kurt Gabathuler
- June 13, 2004

## Pixel Coolant Paths

_**Pixel Coolant Paths**_
***For good pressure regime: inlet via top, outlet via bottom***

**+ z**

**- z**

**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**

**Pixel**
**Cooling**
**Rack**

## Pixel cooling rack

**Pixel cooling rack**

## left

**left**
**half**
**barrel**

**right**
**half**
**barrel**

**disks**
**+z**

**disks**
**-z**

**tank**

**Circulation pump**

**filters**

**Heat**
**exchanger**

## CMS Pixel Detectors and service structures inside the tracker

_**CMS Pixel Detectors and service structures inside the tracker**_

**barrel service**
**half-cylinder**

**half-barrel**

**3 half-disks attached to service structure**

**optohybrids &**
**control electronics**

**+z**

**-z**

**flexible connections**

## Pixel Half Barrel

_**Pixel Half Barrel**_
**3 layers**

_**group of 4 tubes**_

**trapezoidal Al tube**
**with d****hydr****=3mm**
**0.3mm wall thickness**

## Optohybrids

**Optohybrids**

**Cooling channels**

## Frontview of half-barrel

**Frontview of half-barrel**

**Gap between barrel & service tube**

## One of 10 Pixel Barrel Cooling circuits

_**One of 10 Pixel Barrel Cooling circuits**_

- +/- z

- -/+ z

**63 cc/s**

**32 cc/s**

**5********6.4 cc/s**

**31 cc/s**

**4********7.75 cc/s**

**32 cc/s**

**31 cc/s**

**63 cc/s**

**service tube**

**service tube**

**T**

**T+2.0**

**T**

**T+1.6**

## Cooling of quarter disk, Forward Pixel

**Alu 2.5mm x 6 mm, d****hydr****=3.5mm**

**IN**

**OUT**

## Slide 11

## One of 8 forward Pixel Cooling Circuit

- Total pressure drop  ~ 2000 mbar

- Service Tube 4mm id

- Supply 10mm id

- 45cc/s

- 15cc/s

- 1⁄4 disks6 blades

**disk 1**

**disk 2**

**disk 3**

******T=1.8****0**

- 15cc/s

- 15cc/s

## 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 | 5 | 114 | 63 | 540 | 4.9 | 2.0 |
| Disks+z | 4 | 109 | 45 | 345 | 4.3 | 2.0 |
| Disks-z | 4 | 127 | 45 | 365 | 4.4 | 2.0 |
| Total | 18 |  | 990 | 8340 |  |  |

## Additional slides

## pressure transducer

**Barrel +z********-z**
**Total flow 160 or 320 cc/s**
**(layers 1+2 or 3 layers)**

**Disks +z**
**Total flow 60, 120 or 180 cc/s**
**(1, 2, or 3 disks)**

**pressure transducer**
**p ******** 3.5 bar abs.**

**pump: ********p ******** 1.7 bar**
**@ 1 liter / s**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**Bypass**

******P**

******P**

******P**

******P**

**Barrel -z********+z**
**Total flow 160 or 320 cc/s**
** ****(layers 1+2 or 3 layers)**

**Disks -z**
**Total flow 60, 120 or 180 cc/s**
**(1, 2, or 3 disks) **

**manual**
**pressure**
**adjustment**

**manual**
**valves**

**gas inlet**
**to blow**
**coolant into**
**reservoir**

**Reservoir**

**flowmeters**
**or ********p(in/out)**

**heat**
**exchanger**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

**X**

## Slide 16

## Slide 17

## Slide 18

## Slide 19

## Slide 20

## Slide 21

## Barrel+z in high, -z out low

******p1.70, ****0**

**external pressure**
**p****abs**** 3.20, ****3.20**

- 0.69
- 0.92

- 3.20
- 3.20

- 12

- 10

- 10

- 5.2

- 1. 21
- 1.55

- 1.52
- 2.88

- 1.50
- 3.20

- 1.71
- 2.22

- 12

- 12

- 1.02
- 2. 22

- 1.36
- 2.22

- pressures in abs bar, dyn, static

- path length 92.5 m

## Barrel-z in high, +z out low

******p1.59, ****0**

**external pressure**
**p****abs**** 3.20, ****3.20**

- 1.30
- 1.55

- 3.20
- 3.20

- 12

- 10

- 10

- 5.2

- 1.25
- 1.55

- 1.56
- 2.88

- 1.61
- 3.20

- 1.75
- 2.22

- 12

- 12

- 1.06
- 2. 22

- 1.40
- 2.22

- pressures in abs bar, dyn, static

- path length 80.5 m

## Disks+z in high, +z out low

******p1.74, ****0**

**external pressure**
**p****abs**** 3.20, ****3.20**

- 1.11
- 1.22

- 3.50
- 3.50

- 12

- 10

- 10

- 5.2

- 1.69
- 1.85

- 1.56
- 3.18

- 1.76
- 3.50

- 2.28
- 2.52

- 12

- 12

- 0.97
- 2. 52

- 1.62
- 2.52

- pressures in abs bar, dyn, static

- path length 84.3 m

## Disks-z in high, -z out low

******p1.76, ****0**

**external pressure**
**p****abs**** 3.20, ****3.20**

- 1.73
- 1.85

- 3.50
- 3.50

- 12

- 10

- 10

- 5.2

- 1.71
- 1.85

- 1.58
- 3.18

- 1.74
- 3.50

- 2.30
- 2.52

- 12

- 12

- 0.99
- 2. 52

- 1.64
- 2.52

- pressures in abs bar, dyn, static

- path length 87.5 m

## Measurement of flow through the individual cooling pipes of pixel barrel

_**Measurement of flow through the individual cooling pipes of pixel barrel**_

## Coolant Flow Distribution

**35 cc/s**
**(measured)**

**1**
**2**
**3**
**4**
**5**

**Coolant Flow Distribution**
**(C****6****F****14**** at room temperature)**

**35 cc/s**
**(measured)**

**1**
**2**
**3**
**4**
**5**

****** ****12 % variation**

****** ****9 % variation**

## Pressu

- 1⁄4 disks

- 6 blades

**disk 1**

** **

**disk 2**

** **

**disk 3**

** **

- layer 1 or 2

- layer 3

** **

**DISK**

** **

**COOLING**

** **

**CIRCUIT**

** **

**Pressu**

**re drops for staged pixel**

** **

## Summary Pixel Cooling Circuits 

**(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 | 5 | 80.5 | 31.5 | 252 | 4.5 | 0.89 |
| Disks+z | 4 | 84.3 | 30 | 204 | 3.8 | 1.54 |
| Disks-z | 4 | 87.5 | 30 | 204 | 3.8 | 1.56 |
| Total | 18 |  | 555 | 4152 |  |  |