Ventilation systems for HL-LHC (WP17.3)

Ventilation systems for HL-LHC (WP17.3)
Paul Pepinster CERN Engineering Department Cooling and Ventilation Group Cooling and Ventilation Review – 14th March 2017

Content USER REQUIREMENTS DESIGN CRITERIA TECHNICAL DESCRIPTION
Technical requirements Safety requirements DESIGN CRITERIA Surface buildings: Thermal study Reference values Thermal balance Underground area: Required indoor conditions Guidelines / constraints TECHNICAL DESCRIPTION Systems overview Ventilation design for surface buildings Ventilation design for underground area Resulting AHU sizing and power balance International Technical Review of WP17.3, CERN, March '17

Technical requirements Safety requirements DESIGN CRITERIA Surface buildings: Thermal study Reference values Summer thermal balance Winter thermal balance Underground area: Heat dissipations Guidelines / constraints TECHNICAL DESCRIPTION Systems overview Ventilation design for surface buildings Ventilation design for underground area Resulting AHU sizing and power balance International Technical Review of WP17.3, CERN, March '17

Technical requirements Heat dissipations
Underground area Equipment Heat load dissipated in air (kW) URx5 Power converters 45 Water Cooled Cables 30 Energy extraction syst. 1 Transformers, LV switchboards, UPS safe room 63 User racks 68 Faraday cage 8 UAx3 RF amplifier 24 RF HV Power Supply 36 UAx7 USx7 Cold box 20 27 UWx7 Pumps, VSDs 7 Surface building Equipment Heat load dissipated in air (kW) SUx7 Chillers 25 Pumps, VSDs 10 SEx7 LV electrical 11 SHMx7 Helium compressor 200 SFx7 24 SDx7 Cold box International Technical Review of WP17.3, CERN, March '17

Technical requirements Ambient conditions
Underground areas Min. temperature Max. temperature Max. Dew Point control (*) UWx7- USx7- URx7 15°C 25°C 12°C PMx7 safe zone 18°C 26°C Not required ULx3 - ULx7 UAx3 - UAx7 31°C Safe room USx7 20°C Faraday Cage USx7- URx5 21°C 23°C Surface buildings Min. temperature (winter) Max. temperature (summer) SHMx7 18°C Not required SUx7 15°C SDx7 SEx7 35°C/8h SEx7 batteries room 20°C 25°C SFx7 These are the ambient temperatures requested by the users for their equipment (*) to prevent condensation on equipment / (mixed water-cooled) International Technical Review of WP17.3, CERN, March '17

Technical requirements Safety requirements DESIGN CRITERIA Surface buildings: Thermal study Reference values Summer thermal balance Winter thermal balance Underground area: Heat dissipations Guidelines / constraints TECHNICAL DESCRIPTION Systems overview Ventilation design for surface buildings Ventilation design for underground area Resulting AHU sizing and power balance International Technical Review of WP17.3, CERN, March '17

Safety requirements Underground area: Surface buildings
Possible hazards from LHC Possible hazards in HL-LHC area Emergency evacuation safety Air renewal Surface buildings Smoke extraction Hydrogen extraction Infiltrations of radioactive air, smoke through connection cores International Technical Review of WP17.3, CERN, March '17

Possible hazards from LHC
Fire Smoke Helium leak Radioactive air PMx7 UPRx7 UAx3 UAx7 ULx3 ULx7 UPRx3 …and related constraints on ventilation design. International Technical Review of WP17.3, CERN, March '17

Hazards from LHC Radioactive air, Helium, fire and smoke
Pressurised buffer zones + 25 Pa Ventilation door Fire resistant door Fire sectorisation: Isolate a fire in one part of the facility Allow intervention of the fire brigade from a safe point behind the door Connection cores with LHC (cryo / UL, RF / UA) Create 4 pressurised buffer zone International Technical Review of WP17.3, CERN, March '17

Hazards in HL-LHC Smoke compartments
Fire resistant doors Smoke curtains Smoke compartments (#10): to delay the propagation of smoke along the ceiling to create smoke free environment at walking height to allow the safe evacuation of personnel International Technical Review of WP17.3, CERN, March '17

Smoke curtains Fire simulation in URx5 after 112 s and after 400 s
Rigid panels in fire-resistant material H = 2.6 m from the floor Illustrations: courtesy of T. Otto (EDMS ) International Technical Review of WP17.3, CERN, March '17

Pressurised emergency exit paths
In case of fire / He spill in HL-LHC area: Exit by PMx7 shaft Exit by LHC in case the way to PM is cut-off PM lift cage / staircase overpressure +20 to +80 Pa PMx7 UPRx7 UAx7 UA pressurised airlock +25 to +80 Pa UPRx3 UAx3 International Technical Review of WP17.3, CERN, March '17

Smoke extraction System shall be designed to remove smoke from one compartment at a time Required flows are based on the fire load in each compartment 6,000 m3/h 18,000 m3/h 36,000 m3/h International Technical Review of WP17.3, CERN, March '17

Underground area - Air renewal (primary air)
Requirement: Supply fresh air to the underground Remove the humidity gains of the tunnel Maintain Dew Point < 12°C Drains Waterproof membrane International Technical Review of WP17.3, CERN, March '17

Surface buildings extraction
Smoke extraction in all buildings according to applicable rules H2 extraction from batteries rooms in SEx7 He exhaust from SHMx7 in case of ODH detection SEx7 H2 m3/h (batteries for UPS) International Technical Review of WP17.3, CERN, March '17

Technical requirements Safety requirements DESIGN CRITERIA Surface buildings: Thermal study Reference values Thermal balance Underground area: Heat dissipations Guidelines / constraints TECHNICAL DESCRIPTION Systems overview Ventilation design for surface buildings Ventilation design for underground area Resulting AHU sizing and power balance International Technical Review of WP17.3, CERN, March '17

Surface buildings Thermal study
Purpose: Define the concept of insulation for buildings Technical proposal for energy utilization (heating and cooling) Thermal study report is mandatory as part of the building permit request procedure Constraints: P1 / P5 located in different countries: CH / FR Building permit procedures CH / FR are different Applicable rules (e.g. energy matters) are different Same design requested by CERN for P1 and P5 (costs): Same buildings Same HVAC equipment Common thermal study report for FR and CH building permit request Thermal design based on the most constraining rules: Building element Max. Thermal conductivity [W/m2.K] (CH) Max. Thermal conductivity [W/m2.K] (FR) Values chosen Roof 0.4 0.34 Walls 0.45 Doors /windows 2.4 2.6 International Technical Review of WP17.3, CERN, March '17

Surface buildings Reference values for thermal study
Outdoor (*): Indoor: (*) Reference conditions in Geneva, Swiss standard SIA 2028 Summer Winter Temperature [°C] +33.4 -9 Rel. humidity [%] 50 90 Surface Buildings Winter temp. [°C] Summer SDx7 18 35 SEx7 SFx7 SHMx7 40 SUx7 International Technical Review of WP17.3, CERN, March '17

Surface Buildings Thermal balance
Heat Losses (winter) [kW] Heat Loads (summer) (a) USERS Heat Loads (b) COOLING needs (a) + (b) SHMx7 26 7 200 207 SUx7 28 3 21 24 SDx7 4 15 19 SEx7 Low Voltage room 10 2 11 13 SEx7 High Voltage Room 1 SFx7 16 31 AHU design values Building heating needs (Technical Stop) Building cooling needs (LHC in operation) International Technical Review of WP17.3, CERN, March '17

Underground area – Heat loads
Zone USERS heat loads [kW] Half-CC Full-CC Safe room USx7 7 Faraday cage USx7 8 15 Faraday cage URx5 UAx7 60 120 UAx3 URx5 182 USx7 40 UWx7 AHU design values Upgrade of RF equipment International Technical Review of WP17.3, CERN, March '17

Design guidelines (1/2) Design: Cooling: Heating:
Same for P1 and P5 (consistency, costs) ISO and EN standards, Host States rules (most constraining) Cooling: Free cooling: For surface building: SD, SE, SF, SHM, SU Toutside = 30°C taken as design value, beyond which ambient conditions can drift (60h/year) Cooling coils: Underground area 14°C/20°C “mixed water” for temperature control applications 5°C/10°C “chilled water” for humidity control applications Heating: HL-LHC Point 1: Connection to remote heating network (Meyrin site heating plant) Water 80/60°C, available from October to May HL-LHC Point 5: Electrical heating Heat recovery when possible Fresh air for surface buildings: 36 m3/h.person Free cooling as much as possible International Technical Review of WP17.3, CERN, March '17

Design guidelines (2/2) Redundancy: Underground space occupancy:
AHUs related to safety requirements: Pressurisation of PM shaft (safe zone) and underground airlocks (UA, UL) Safe room in USx7 (safety systems) Fresh air distribution AHUs critical for machine operation: SE, Faraday cages Controls and power supplies Level N+1 NB: all equipment are accessible all the time, underground included Underground space occupancy: Optimise equipment dimensions Tackle heat loads at the source as much as possible (min. ductworks) Half Crab Cavities vs Full Crab Cavities: Only ventilation of UA galleries and Faraday cages will require to be upgraded Sizing margins: + 15% (heating and cooling powers, flowrate) International Technical Review of WP17.3, CERN, March '17

Overview of the ventilation systems (General synoptic)
SHMx7 SEx7 SUx7 SDx7 SFx7 PMx7 UAx3 UAx7 ULx7 ULx3 FC USx7 UWx7 URx5 SR International Technical Review of WP17.3, CERN, March '17

Underground Ventilation
PM PRIMARY AIR FROM SU (*) 4 fans for each airlock between UA and LHC tunnel (*) UA UL UL UA UW UR US X 6 International Technical Review of WP17.3, CERN, March '17

Safe rooms and Faraday cages
PM UA UL UL UA UW UR US Faraday Cage Safe Room Redundant AHUs in 2 different fire compartments International Technical Review of WP17.3, CERN, March '17

SHM, SE and SF Ventilation
HV LV SF F International Technical Review of WP17.3, CERN, March '17

SUx7: Ventilation Building
Heat recovery SU Safe Room H2 extraction PM - pit SU PM - Lift cage US UW UR UA_7 UL_7 UL_3 UA_3 SD Ventilation Ventilation Lift cage overpressure Fresh air International Technical Review of WP17.3, CERN, March '17

SUx7: Ventilation Building
F Smoke extraction SU PM - Lift cage US UW UR UA_7 UL_7 UL_3 UA_3 PM - pit SD SU Ventilation Compensation air from SD door opening Ventilation Lift cage overpressure Fresh air International Technical Review of WP17.3, CERN, March '17

Ventilation of SHMx7 International Technical Review of WP17.3, CERN, March '17

Ventilation of SHMx7 SHM SHM kW 7 200 20.6 kW 26 30 000 m3/h
42°C 18°C m3/h m3/h 30°C 21°C SUMMER / OPERATION Building heat load kW 7 User heat load 200 AHU Motor 20.6 Total 227.6 Considered Δ𝑇 K 12 AHU Size m3/h 60 000 Mixing rate v/h 8.4 WINTER / MAINTENANCE Building heat losses kW 26 Installed heating power 30 AHU low speed m3/h 30 000 Δ𝑇 K 3 International Technical Review of WP17.3, CERN, March '17

Ventilation of SHMx7 – P&ID
International Technical Review of WP17.3, CERN, March '17

Ventilation of SHMx7 – P&ID
Heating water (P1) Electricity (P5) International Technical Review of WP17.3, CERN, March '17

Fresh air supply to underground area (primary air)

Sizing parameters: AHU main features: Design basis reference: Tunnels humidity output: 3gw/h/m2 Size m3/h 16 000 Recovery coil kW Winter: ~+73kW Summer:~−23kW Central heating coil 60 Cooling coil 250 Post-heating coil 50 Full fresh air AHU Energy recovery coil with air returning from the tunnels Post-heating with heat recovery on chillers condensation water Calculation details Tunnel humidity output gw/h/m2 3 Tunnel surface area m2 12 198 Humidity output gw/h 36 594 Max. air humidity gain gw/kgair 2.30 Min. air flow rate m3/h 13 261 AHU Size (+15%) 16 000 International Technical Review of WP17.3, CERN, March '17

-9ºC HR 90% Energy recovery / air returning from winter 17ºC HR 14% 17ºC HR 54% 33.4ºC HR 50% Winter Pre-heating (recovery / air ) Heating (remote net.) Summer Pre-cooling (recovery / air) Cooling / deshumid. Post-heating (recovery / chillers) International Technical Review of WP17.3, CERN, March '17

PMx7 shaft pressurization (safe zone)

PMx7 shaft pressurization Lift cage and staircase (evacuation safety)
Sizing parameters: AHU main features: Size m3/h 12 000 Heating coil kW 120 Back-up electrical heating coil 90 Cooling coil 80 Indoor conditions: min. 18°C in winter Max. 26°C in summer Create an opposite airflow through exit door: Speed: 0.5 m/s Door size / area: 5.7 m2 Required Flowrate: m3/h Full fresh air AHU No humidity control Heating coil either with central heating or heat recovery system Backed-up with electrical heating coil From -9°C to 12°C International Technical Review of WP17.3, CERN, March '17

Pressurisation of lift cage in PMx7
Winter Backup 33.4ºC Summer Heat recov. / condensers Mixed water International Technical Review of WP17.3, CERN, March '17

UA airlocks LHC UPR UA fans: UPR fans: HL-LHC (UA) Airlock +25 Pa
Sectorisation door (grid) Pressure + fire resistant door Ventilation + fire resistant door Ventilation + sectorisation door UA fans: Maintains the airlock at +25 Pa in normal operation Redundant UPR fans: Protect the evacuation path (+20 Pa / +80 Pa) International Technical Review of WP17.3, CERN, March '17

UA airlocks LHC UPR Normal operation: HL-LHC (UA) all doors are closed
Sectorisation door (grill) Pressure + fire resistant door UPR Ventilation + fire resistant door Normal operation: all doors are closed UA-side fan is ON Airlock against radioactive from HL-LHC Airlock +25 Pa Ventilation + sectorisation door HL-LHC (UA) International Technical Review of WP17.3, CERN, March '17

UA airlocks LHC UPR Fire / He leak detection in HL-LHC area:
+20/80 Pa Sectorisation door (grill) Pressure + fire resistant door UPR Ventilation + fire resistant door Fire / He leak detection in HL-LHC area: UA-side fan STOP UPR-side fan STARTS to ensure +20 Pa to +80 Pa overpressure in the SAS Airlock +25 Pa Ventilation + sectorisation door HL-LHC (UA) International Technical Review of WP17.3, CERN, March '17

UA airlocks LHC UPR Evacuation: HL-LHC (UA) UPR-side fan ON Airlock
+0 Pa Sectorisation door (grill) Pressure + fire resistant door UPR Ventilation + fire resistant door Evacuation: UPR-side fan ON Personnel evacuate from UA  LHC Airflow in opposite direction prevents smoke from following them EVACUATION Ventilation + sectorisation door HL-LHC (UA) International Technical Review of WP17.3, CERN, March '17

UA airlocks LHC Sizing of the fans:
+0 Pa Sectorisation door (grill) Flowrate sized according to French Rule IT246: Counter-flow through exit door: 0.5 m/s Door size / area: 2 m2 Required Flowrate: 3600 m3/h UA-side fans sized to compensate air leaks of the SAS: Volume of the SAS= +/- 50 m3 4 vol/h = 200 m3/h Pressure + fire resistant door UPR Ventilation + fire resistant door EVACUATION Ventilation + sectorisation door HL-LHC (UA) International Technical Review of WP17.3, CERN, March '17

ULx3 – ULx7 pressurisation
LHC UL Parameters Value Overpressure +25 Pa Cores estimated leak area 675 cm2 Door leak / EN12207 tightness class 4 1.2 m3/h Fan flowrate 940 m3/h UR or US International Technical Review of WP17.3, CERN, March '17

Ventilation of USx7 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of USx7 UW US kW 40 7 m3/h 16,000 Heat loads Equipmen
26°C 17°C 16,000 m3/h Heat loads Equipmen kW 40 AHU Motor 7 Total 47 AHU features Size m3/h 16,000 Installed cooling power kW 55 Δ𝑇 K 9 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of USx7 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Smoke extraction system

Smoke extraction 6 extractors (N+1):
2 x 6000 m3/h, 2 x m3/h, 2 x m3/h all on the same duct 1 extractor is started at a time Depending on the “smoke zone”: start up 6000 m3/h (UL galleries) start up m3/h (UA, UR comp., UW cavern) start up m3/h (US cavern) Fire brigade select the zone: smoke dampers open in the zone extraction fan(s) start up Redundancy N+1 International Technical Review of WP17.3, CERN, March '17

Resulting AHU features and power balance (underground area)
Function / zone No of AHUs Unit flow rate (m3/h) Total cooling power on mixed water (kW) UAx3 RF amplifiers + HV Power Supply 1 15 000 80 (160) UAx7 URx5 Power converters – Water-cooled cables - Energy Extraction – Racks 6 11 500 240 Faraday cage 1+1 4600 11 (20) USx7 Safe room 3000 10 UWx7 Safe room back-up US cavern 16 000 55 UW cavern 3500 12 Total Power 509 (687) International Technical Review of WP17.3, CERN, March '17

Resulting AHU features and power balance (surface buildings)
Function / zone No of AHUs Unit flow rate (m3/h) Heating power on remote heating (kW) Cooling power on chilled water Cooling power on mixed water Heat recovery SUx7 Pressurisation shaft 1+1 12 000 120 - 80 Primary air 16 000 60 250 50 SU building 1 34 000 35 SD building 30 SHMx7 SHM building 60 000 SFx7 SF building 14 000 20 SEx7 SE – LV 10 000 15 SE – HV 3000 Total power 325 265 International Technical Review of WP17.3, CERN, March '17

Thanks for your attention. Questions?

Backup slides: Design of surface buildings ventilation systems

Ventilation of SEx7 International Technical Review of WP17.3, CERN, March '17

Ventilation of SEx7 (LV room)
HV LV SE F HV LV 35°C / 8h m3/h 15°C 5000 m3/h 30°C 25°C SUMMER / OPERATION Building heat load kW 2.4 User heat load 11 AHU Motor 2.8 Total 16.2 Considered Δ𝑇 K 5 AHU Size m3/h 10 000 Mixing rate v/h 9.3 WINTER / MAINTENANCE Building heat losses kW 10 Installed heating power 15 AHU low speed m3/h 5000 Δ𝑇 K International Technical Review of WP17.3, CERN, March '17

Ventilation of SEx7 (HV room)
LV SE F HV LV 35°C / 8h 3000 m3/h 3000 m3/h 18°C 100% 30°C 28°C SUMMER / OPERATION Building heat load kW 1 User heat load Total AHU low speed m3/h 0 below 35ºC WINTER / MAINTENANCE Building heat losses kW 10 Installed heating power 15 AHU Size m3/h 3000 Δ𝑇 K Mixing rate v/h 3.4 International Technical Review of WP17.3, CERN, March '17

Ventilation of SEx7 – P&ID

Ventilation of SEx7 (P&ID of LV room)

Ventilation of SEx7 (P&ID of HV room)

Ventilation of SFx7 International Technical Review of WP17.3, CERN, March '17

Ventilation of SFx7 SF SF kW 3 27.7 5 kW 16 SUMMER / OPERATION
38°C 18°C m3/h 7000 m3/h 100% 30°C 27°C SUMMER / OPERATION Building heat load kW 3 User heat load 27.7 AHU Motor 5 Total 35.7 Considered Δ𝑇 K 8 AHU Size m3/h 14 000 Mixing rate v/h 4.1 WINTER / MAINTENANCE Building heat losses kW 16 Installed heating power 20 AHU low speed m3/h 7000 Δ𝑇 K 9 International Technical Review of WP17.3, CERN, March '17

Ventilation of SFx7 International Technical Review of WP17.3, CERN, March '17

Ventilation of SUx7 International Technical Review of WP17.3, CERN, March '17

Ventilation of SUx7 SU SU kW 3 39.4 12.1 kW 28 SUMMER / OPERATION
35°C 18°C m3/h m3/h 100% 30°C 24°C SUMMER / OPERATION Building heat load kW 3 User heat load 39.4 AHU Motor 12.1 Total 54.5 Considered Δ𝑇 K 5 AHU Size m3/h 34 000 Mixing rate v/h 4.4 WINTER / MAINTENANCE Building heat losses kW 28 Installed heating power 35 AHU low speed m3/h 18 000 Δ𝑇 K 6 International Technical Review of WP17.3, CERN, March '17

Ventilation of SUx7 International Technical Review of WP17.3, CERN, March '17

Ventilation of SDx7 International Technical Review of WP17.3, CERN, March '17

Ventilation of SDx7 SD SD kW 4.4 10 4.2 kW 26 SUMMER / OPERATION
35°C 18°C m3/h 6000 m3/h 100% 30°C 30°C SUMMER / OPERATION Building heat load kW 4.4 User heat load 10 AHU Motor 4.2 Total 18.6 Considered Δ𝑇 K 5 AHU Size m3/h 12 000 Mixing rate v/h 1 WINTER / MAINTENANCE Building heat losses kW 26 Installed heating power 30 AHU low speed m3/h 6000 Δ𝑇 K 12 International Technical Review of WP17.3, CERN, March '17

Ventilation of SDx7 International Technical Review of WP17.3, CERN, March '17

Surface buildings Smoke extraction in all buildings according to applicable rules H2 extraction from batteries rooms in SEx7 He exhaust from SHMx7 in case of ODH detection SEx7 H2 m3/h (batteries for UPS) Natural smoke extraction equipment Heat and Helium roof exhausts International Technical Review of WP17.3, CERN, March '17

Backup slides: Design of underground ventilation systems

Ventilation of UWx7 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of UWx7 UW kW 7.7 2.4 m3/h 3,500 Heat loads Equipment
26°C 17°C 3,500 m3/h Heat loads Equipment kW 7.7 AHU Motor 2.4 Total 10.1 AHU features Size m3/h 3,500 Installed cooling power kW 12 Δ𝑇 K 9 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of UWx7 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of Safe room
To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

UW US Safe Room 26°C 3,000 m3/h 3,000 m3/h 17°C Heat loads Equipment kW 7 AHU Motor 0.8 Total 7.8 AHU features Size m3/h 3000 Installed cooling power kW 10 Δ𝑇 K 9 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of UAx3 & UAx7

UW 31°C 31°C UR US 17°C 15,000 m3/h 17°C 15,000 m3/h Heat loads Equipment kW 60 AHU Motor 6.5 Total 66.5 AHU features Size m3/h 15,000 Installed cooling power kW 80 Δ𝑇 K 14 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of URx5 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of URx5 UR kW 182 19 m3/h 6 x 11,500 Heat loads Equipment
25°C 17°C Heat loads Equipment kW 182 6 x AHU Motor 19 Total 201 AHU features Size m3/h 6 x 11,500 Installed cooling power kW 40 each Δ𝑇 K 9 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of URx5 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Ventilation of Faraday Cages

UR US Faraday Cage Faraday Cage Air displacement units to favour stratification Heat loads Equipment kW 8 AHU Motor 1.3 Total 9.3 AHU features Size m3/h 4,600 Installed cooling power kW 11 Δ𝑇 K 6 To edit speaker name go to Insert > Header & Footer and apply to all slides except title page

Heat load dissipation to the ground in the HL-LHC
At 100 m depth, the ground temperature is estimated to be 14°C. 300 m of Tunnel at 25°C (summer). Heat load dissipated to the ground with different inputs: Results: From 8 to 31 kW. Internal C&S review of WP17, CERN, September '16

Ventilation systems for HL-LHC (WP17.3)

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