CPPM Pixel Evaporative Cooling Plant

Description & Operation with C3F8 or C4F10

G. Hallewell, CPPM, Feb 07, 2005

System Features Compressor Driven (Haug oil-less piston compressor) Long history of use with C3F8 at CERN (`98`01)

Condenser operable with water at variable temperature:

5ºC for C3F8 at normal operating temp, 55ºC for C4F10 in warm test mode (tested at CPPM)30 metre supply and return tubes as @ ATLASVariable flow control based on power

dissipated along bi-stave Optional pre-cooling (2nd circuit) Partially integrated with PVSS2 control system Full automation under PVSS2 in work

Condenser

Compressor

P

P

Buffer

Viewglass

VMFM BPR

Pixel bistave

V3H2O

SYMBOLSR = regulator (dome loaded)BPR = back-pressure regulator (dome loaded)V = valve (hand operated)Vp = valve (pneumatically operated)MFM = mass-flow meter (Vapor only)V3 = 3 way (by-pass) valve (water only)

Vp

Filters/dryers

Vacuum port

Simplified schematic of CPPM Evaporative Cooling System

Lineprecooling

VV

V

V

V V

V V

V

Vp

Precoolingcapillary

Bistavecapillary

Specialistby-pass

P

P

P

P

V

Vp

Vp

Vp

Vp

Vp

Pixflow

PCflow

RR

V

V

P

Condenser

Compressor

P

PID

MSC

P

V

Buffer

Viewglass

VMFM

CompR404A

BPR

Pixel bistave

V3H2O

PID

Vacuum port

SYMBOLSR = regulator (dome loaded)BPR = back-pressure regulator (dome loaded)V = valve (hand operated)Vp = valve (pneumatically operated)MFM = mass-flow meter (Vapor only)V3 = 3 way (by-pass) valve (water only)MSC= motor speed controllerPID = Proportional, Integral and Derivative AutomatSV = safety valve

Vp

Filters/dryers

Heat Exchanger

(R404 C3F8)

2 pneumatic isolation valves, one bypass, one vacuum port (bistave only)

Vacuum port

Full schematic of CPPM Evaporative Cooling System, including controls & valves

Lineprecooling

VV

V

V

V

V V

V V

V

Vp

A

C

D

E

G

F

H

H

I

I

Precoolingcapillary

Bistavecapillary

Specialistby-pass

sv

Sv

Sv

P

P

P

P

V

B

VpK

Vp

L

Vp

J

J

Vp

Vp

Pixflow

PCflow

RR

MV

NV

P

V4 bar a

4 bar a

10 bar a

Vacuum port

VVacuum port

V

Vacuum port

Main ON/OFF switch

Motor Speed Controller

Compressed Air Valve

PID Controllerfor compressor input pressure

PID Controllerfor condenser

CompressorPreheating Switch

CompressorPower Switch

Preheating Automate (finite state machine)

Valve C

Valve D

Valve F

Specialist By-pass Valve

HumidityView-port

Plug strip(controllers& Massflow

Meter)

PrecoolingFlow Controller

Pixel StaveFlow Controller

Mass Flow Meter(vapour return)

C3F8 input Manifold pressure

Pixel Stave C3F8 input pressure

Precooling line C3F8 input pressure Common Exhaust C3F8

evaporation pressure

Air PressureTo Circuit 2

Pre-cool

Air Pressure To Circuit 1

Pixel

Air Pressure toCommon Exhaust

MassflowMeter

Electronics

MassflowMeter

Valve N Valve L

Valve G

Valve M

Valve B

Valve C

CondenserWater Valve

Valve A

Vacuum pump outport and fill valve

Pixel Stave dome-loaded flow regulator

Precooling dome-loaded flow regulator

Pixel Stave dome-loaded flow regulator

Pixel Stave electronicpressure gauge

Dome-Loaded Flow regulators (rear view of rack)

Variable Pressure compressed air hoses

Dome-Loaded Exhaust Back-Pressure regulator (rear view of rack)

Pixel Stave dome-loaded flow regulator

Variable Pressure compressed air hose

Exhaust electronicpressure gauge

Hoerbiger VP converters for sending analog compressed airto dome-Loaded regulators (rear view of rack)

Pixel Stave Hoerbiger

Precooling Hoerbiger

Exhaust Hoerbiger

Compressed AirFilter

Compressed AirSupply

Compressed AirRegulator for

Exhaust Hoerbiger

Compressed AirRegulator for

Pixel and Precooling Hoerbigers

Pixel Stave Valve Control Electronics

Cable to solenoid valves

Connection block forE-LMB signals

I1

I2

H1

H2

J1

J2 K

Anti-condensationAir purge

Precooling Capillary (under insulation)

Downstream PT100 & NTCTemperature sensors

Upstream PT100 & NTCTemperature sensors

C3F8 Pressure-Enthalpy diagram

C4F10 Pressure-Enthalpy diagram

Condenser at 55ºC (instead of 5ºC for C3F8 )

Pneumatic Valve Panel FSM : “Cooling state”:

Valves H1, H2, I1 & I2 have been commanded to open and have opened

Example (1) of PVSS2 operation: stave cooling

Pneumatic Valve Panel FSM: “Pump-out State”:

Valve H1, H2, I1 & I2 closed; Valves J1 & J2 commanded to open and open

Example (2) of PVSS2 operation: stave pumpout

Pneumatic Valve Panel FSM : Shut-down State

Example (3) of PVSS2 operation: shut down

Example of PVSS2 sensor data readout

Thermal behaviour of Stave 4012 (°/W)

0

0,5

1

1,5

2

2,5

3

3,5

0 2 4 6 8 10 12 14

chiller /individual power supply

C3F8 Evap/individual

C3F8 Evap/all on

C3F8 Evap 1/all on

Thermal behaviour of stave 4012 (ºC/Watt),C3F8 evaporative and Chiller

Carbon-carbon plate boundary

Module #

ºC/W

10

12

14

16

18

20

22

24

12:43:12 13:12:00 13:40:48 14:09:36 14:38:24 15:07:12 15:36:00 16:04:48

time

temp

Mod 00

Mod 01

Mod 02

Mod 03

Mod 04

Mod 05

Mod 06

Mod 07

Mod 08

Mod 09

Mod 10

Mod 11

Mod12

PC4F10feed

Pcondenser

p5_2

Tevap

Tevap dist

Tamb

C4F10 Study, Stave 4012, 20 Dec 04

Modules ‘configured’ + cooled Modules off + cooled

Note: module numbering runs 0-12, not 1-13 as in previous + next slides

0

0,5

1

1,5

2

2,5

3

3,5

4

4,5

5

0 2 4 6 8 10 12 14

Module #

Deg

C pe

r Wat

t (re

l. tu

be)

Rel to Tube

Mod.on-Mod.off

Direction of fluid flow

Thermal behaviour of stave 4012 (ºC/Watt), C4F10

Carbon-carbon plate boundary

Conclusions CPPM compressor-powered evaporative cooling system

can operate satisfactorily with C3F8 and C4F10.

There is no problem of principle to warm test with C4F10 in SR1 with 30m tubing runs

Similar offsets in ºC/W seen with stave 4012 with C3F8 and C4F10; we note different thermal impedances of the 2 pieces of C-C used to make the stave

Modules 9, 10 have higher power (4.22, 3.63W) than other modules, with some evidence of fluctuation, (manifested on modules 7, 8 downstream in flow direction)