Where s the Heat Coming From. Leland Sparks Global Account Technical Consultant Belden

Transcription

1 Where s the Heat Coming From Leland Sparks Global Account Technical Consultant Belden

2 What is the greatest DC challenge you face?

3 Air Flow to Heat Load Relation Server Inlet Fans Chips Outlet LOAD Dell 1855 Blade Centers T1 CFM kw T2 100% of the power supplied to IT gears is transferred into heat

4 Air Flow to Heat Load Relation At sea level, heat is transferred to air according to; CFM = 3160 * kw / ΔT Server Inlet Fans Chips LOAD Outlet Where CFM = Cubic Feet per Minutes kw = Kilos Watts ΔT = T 2 - T 1 (ºF) T1 CFM kw T2 For ΔT = 36º F (ref. Dell) and 1kW load CFM = 3160 (1kW) / 36º F = 88 CFM

5 Servers OEM challenge Reducing energy consumption Older (3Y) Server, ΔT = 26 ºF consume 120CFM per kw of load Typical (Today) Server, ΔT = 32 ºF consume 100CFM per kw of load Energy Stars Server, ΔT = 39 ºF consume 80CFM per kw of load Smart > consumption = f(computing state)

6 Environmental guidelines ASHRAE Environmental guidelines for datacom equipment TC T 1 = ºC (68-77 ºF) % Relative Humidity 2009 T 1 = ºC ( ºF) % Relative Humidity

7 CRAC Data Center 101 Hot/Cold Aisles Concept CRAC = Computer Room Air Conditioning unit Raised floor tiles are typically 24 x 24 Solid tiles in hot aisles, graded/perforated tiles in cold aisles Rack = Cabinet = Enclosures 24 W x 42 D x 84 H (44RU) typical Average installed power density = 1.5>2kW/cabinet

8 Traditional Cold / Hot Aisle Supply air/cold side Return air/hot side deployment Substantial mixing of hot & cold air leads to hot spots Mixed air leads to low CRAC/CRAH return temperatures, decreasing cooling efficiency Floor tile gymnastics are required to attempt to handle or eliminate hot spots Environment must be micromanaged as adds, moves and changes move heat loads

9 Data Centers are environmentally unstable The enemies > Bypass air, Air flow Recirculation Uptime Institute Study (1) 19 data centers, 204,000 sq-ft of floor, 15,000 measurements On average 2.6 times more cooling is being delivered than is required by the IT equipment load 60% of the cool air that is generated by computer room air conditioning units is not getting to the intakes of the IT equipment but rather is short cycling back to the cooling unit 10% of the racks where still experiencing hot spots (intake temperature above 77 ºF) Hot spots at the IT Equipment intakes cause premature failure, active OEM warranty issues Cool air is exiting through perforated floor tiles and floor cable cut-outs and is returning to the cooling unit unused > Bypass Air Hot air is cycling back to the IT equipment intake > Air Flow Recirculation (1) White Paper Reducing bypass airflow is essential for eliminating computer room hot spots

10 Data Centers Challenges Power consumption density is increasing Peak Electrical Demand of 16 Houses 1 X 42RU Blade Server Rack = 84 x 24 x 42 Dell 1855 Blade Cente

11 Instability = Complexity IT equipment intake temperatures are compromised by high heat loads and recirculation of the exhaust heat Excessive cooling oversupply is the most common method to reduce IT equipment intake temperatures Delivering more air and at lower Hot Hot Cold Cold temperatures Aisle Aisle Aisle is inefficient and does Aisle not produce predictable CRAC results CFD modeling CRAC

12 Warnings from IT Equipment OEMs Dell on server thermal issues from hot air recirculation due to downstream pressure on server fans Reference: 7x24 Exchange Conference Boca Raton 2008, David Moss

13 Short Term Fix

14 Cooling Options 42u Cooling Fans 42u Cooling Mini Air Conditioner

15 Air flow management cold aisle containment

16 Cold Aisle Containment - Under floor air pressure balance is critical to achieve balanced cooling in all aisles - Oversupply of air to maintain under floor pressures leads to wasted fan energy - Not suitable for slab environments - Majority of white space is hot aisle leading to undesirable working conditions - Doors and ceiling of containment can lead to challenges in lighting and fire suppression

17 Let s build a Dc, hot aisle containment

18 Hot Aisle Containment - High containment aisle pressures lead to wrap around heating - Doors and ceiling of containment can lead to challenges in lighting and fire suppression - High containment aisle pressure force server fans to speed up, increasing fan speed energy and decreasing cooling efficiency

19 Cabinet Level Containment Passive and Active Cabinet (24 W x 84 H 44RU x 42 D), 12 KW per cabinet current. Capability to increase to 20KW. Solid rear door, rail seal kit, use of blanking panel on open RU. Side panels and separator panels between cabinets.

20 Cabinet Level Containment Support of high density applications Consistent server inlet temperatures Higher return temps=greater CRAC/H efficiency Reduced energy costs Unlock stranded cooling capacities

21 Facebook to Sweden

22 Adaptive Enclosure Heat Containment Physical separation of the hot and cold air, lower cooling cost by 30-50% Separation predictable airflow paths, Controlled/Stable environment Eliminates Bypass Air and Air Recirculation/Mixing Reduce or eliminate cool air oversupply (2.5 to <1.2) Elimination of hot spots, increase IT equipment availability Allows for high density deploy (up to 30KW/rack) without precision cooling Increase supply air temperature (8-10 degree) Increase return air temperature to CRAC (increase CRAC efficiency) Allow deploy of high density computing anywhere in the data center (increased flexibility) Build in environmental, air flow monitoring/alarming AC Rack Rack Rack Rack

23 Deploy discussion High Density clusters deploy

24 Deploy discussion Sharing containment between 2 or 3 cabinets Low-Medium Density on Racks without Divider Panels

25 AEHC Fully Managed, Intelligent system

26 Air Flow management containment no raised floor scenario hot air return duct ducted air supply no drop ceiling Create separation between cold and hot side Define path of return to CRAC units

27 Retrofit to existing

28 Heat Containment Forcing separation between cold and hot side 105 ºF 75 ºF

29 AEHC System Components AEHC Chimney, allows connection to drop ceiling Custom height project specific AEHC Fan Cartridge 2 per Chassis AEHC Chassis H x W x D inches Chassis Adaptor plate Belden AEHC can be retrofitted to third party enclosure Custom adaptor plate required AEHC Pressure sensor Enclosure rear AEHC Host/Controller Enclosure requirement Perforated front door Solid side panels or separator panels Solid rear door Unused Rack Unit must be blocked using blanking panels Rails sealing kit to be used Optimal for XUSD 42 deep or 48 enclosure

30 AEHC Host / Controller

31 Passive cabinet level containment 3-5Kw

32 Passive cabinet level containment 10 Kw

33 Active Containment Constant speed fans

34 AEHC ROI combine with Green

35 Questions???