Read Microsoft PowerPoint - 7x24 Feb 2005.ppt text version

Current HVAC Design Issues in Data Centers

Presented to 7x24 Exchange Northwest Chapter

February 8, 2005

Presentation Goals & Outline

· Power Density ­ Where we have been, where we are now and where we are going · Limitations of Air Cooling ­ Air Distribution, Effectiveness and Heat Removal · What Does ASHRAE Say? · Unified System Solutions · Energy Efficiency

Current HVAC Design Issues in Data Centers

Common Data Center Scene

Have you seen data centers that look like this?

Current HVAC Design Issues in Data Centers

Thermophoto Analysis

Current HVAC Design Issues in Data Centers

IT Equipment Trends

This area is for the equipment footprint only! Power density is diluted when the entire data center area is added.

*from The Uptime Institute (http://207.201.136.39/TUIpages/whitepapers/tuiheat1.0.html)

Current HVAC Design Issues in Data Centers

Issues in the Data Center

The rise of heat densities at the microprocessor level (watts)

Current HVAC Design Issues in Data Centers

Blade Servers

25 20 15

kW/Cabinet

10 5 0

Pre P3 Processor P3 Mobile Blade P4 Blades/P4 Multi- NextGen Ultra P4 Single Processor 1U & 2U Dense Blade & Processor 1U Server High-End Enterprise Servers

Current HVAC Design Issues in Data Centers

How Do We Remove the Heat?

Water · Water has 3500 times more heat capacity than air by volume Air · Overhead · Underfloor

Current HVAC Design Issues in Data Centers

Are We Hitting the Wall?

· "The failure rate at the top third of the rack is three times greater than at the bottom."

­Mr. Kenneth Brill, Executive Director: The Uptime Institute, March 2003 DataCenter Dynamics Conference)

· The wall is at 3.5 KW/Cabinet (with raised floor) · Without raised floor, 2.5 KW/Cabinet max.

­Steve Spinazzola, RTKL, Oct. 2004, 7x24

Current HVAC Design Issues in Data Centers

Overhead Air Distribution

· Limitations to capacity due to duct size / space constraints · Higher cost for ductwork versus underfloor system

Current HVAC Design Issues in Data Centers

Underfloor Air Distribution

· Increased floor depth for higher flows · Limitation of perf tiles (400 cfm = +-2.5 kW/rack) · UF obstructions · Air Maldistribution ­ underfloor velocity/static pressure · Air plumes

Current HVAC Design Issues in Data Centers

The Cause of Flow Maldistribution

Current HVAC Design Issues in Data Centers

Abovefloor Plumes

Rack total airflow: 700cfm Rack total airflow: 1400cfm Rack total airflow: 350cfm Max inlet temp: 18 C/64 F Max inlet temp: 28 C/82 F Max inlet temp: 16 C/61 F

Current HVAC Design Issues in Data Centers

Underfloor Plumes

1 kW / Cabinet ­ 24" Raised Floor Velocity vectors & pressure (inch wg ) under the raised floor

Row

Column

Current HVAC Design Issues in Data Centers

HVAC Effectiveness

· Bypass Airflow · Air Distribution Efficiency

­ 70% of cooling supply air is wasted and bypasses back to return system.

Current HVAC Design Issues in Data Centers

ASHRAE Standards

Key Points to ASHRAE TC9.9

­ Equipment Environmental Specifications ­ Equipment Room Airflow ­ Standardize Measuring / Monitoring Points ­ Equipment Airflow Protocol Syntax ­ Equipment Manufacturer's Heat Reporting

Current HVAC Design Issues in Data Centers

ASHRAE Standards

Table 2.1 Equipment Environment Specifications

Equipment Environment Specifications

Product Operation a,b Max. Dew Point (ºF) Product Power Off b,c Max. Dew Point (ºF)

Max. Elevation (m)

Clas s

Dry-Bulb Temperature (ºF)

Relative Humidity (%) Non-Condensing

Dry-Bulb Temperature (ºF)

Relative Humidity (%)

Max Rate of

Allowable

Recommended

Allowable

Recommended

1

59 to 90 d

68 to 77

20 to 80

40 to 55

63

3050

5

41 to 113

8 to 80

81

2

50 to 90 d

68 to 77

20 to 80

40 to 55

70

3050

5

41 to 113

8 to 80

81

3

41 to 95 d,e

N/A

8 to 80

N/A

82

3050

N/A

41 to 113

8 to 80

84

4

41 to 104 d,e

N/A

8 to 80

N/A

82

3050

N/A

41 to 113

8 to 80

84

Current HVAC Design Issues in Data Centers

ASHRAE Standards

Equipment Room Airflow

Current HVAC Design Issues in Data Centers

ASHRAE Standards

Key Points to ASHRAE TC9.9 (continued)

­ Standardize Measuring / Monitoring Points ­ Equipment Airflow Protocol Syntax ­ Equipment Manufacturer's Heat Reporting

Current HVAC Design Issues in Data Centers

The New Paradigm

Extraction Versus Dilution

Current HVAC Design Issues in Data Centers

Hot & Cold Aisle - Plenum

CEILING (RETURN) PLENUM

FLEXIBLE AIR BARRIER (TYP.)

COLD AISLE

COLD AISLE

RACK/CABINET

RACK/CABINET

HOT AISLE

HOT AISLE

RAISED FLOOR (SUPPLY) PLENUM

Current HVAC Design Issues in Data Centers

RACK/CABINET

CRAC UNIT

General Points

General Ideas and Points

· No cabinet doors. · Cable management behind servers in "hot" aisle. · Limit air bypass ­ use rack blanking panels and seal all floor cutouts. · Limit mixing between hot and cold aisles.

­ Lexan panels above racks and doors at aisle ends. ­ Sprinklers / FP piping in each aisle.

Current HVAC Design Issues in Data Centers

Hot & Cold Aisles ­ All Overhead

CEILING (RETURN) PLENUM DUCTED SUPPLY

FLEXIBLE AIR BARRIER (TYP.)

COLD AISLE

COLD AISLE

RACK/CABINET

RACK/CABINET

HOT AISLE

HOT AISLE

Current HVAC Design Issues in Data Centers

RACK/CABINET

CRAC UNIT

Power Use in Tech Spaces

Fan Cooling UPS 5% 9% 20% 65% 25% Cooling Technology Load Full Load Technology Load Actual Part Load

Current HVAC Design Issues in Data Centers

Lighting 1%

UPS 9% Fan 20%

Lighting 3%

43%

Energy Conservation

· More efficient equipment power supplies · Water-cooled vs. air-cooled · Variable speed drives · Plenum fan vs. housed fan · Minimize operating redundant equipment · Air-side economizers · Water-side economizers · Tightly controlled air flow · Split circuited coils for humidity

Current HVAC Design Issues in Data Centers

Sacramento Weather Profile

(Dry Bulb Data)

1400

Annual Hours of Occurrence - Hrs

1200

Free Cooling With Exhaust Air Flow Management

1000

800

600

400

200

Free Cooling

12.5 22.5 32.5 42.5 52.5 62.5

Evaporative Cooling

72.5 82.5 92.5 102.5

0

Outdoor Ambient Dry Bulb - F

Current HVAC Design Issues in Data Centers

Summary

· Understand the limitations of air cooling · Focus on heat removal · Understand part load operating conditions · Look for energy efficiency opportunities

Current HVAC Design Issues in Data Centers

Speaker Contact Information

John M. Pappas, PE, LEED AP

Principal [email protected]

Mazzetti & Associates Consultants & Engineers 530 Bush Street San Francisco, CA O: (415) 362 - 3266 F: (415) 362 ­ 3267 C: (415) 652 - 4184

Current HVAC Design Issues in Data Centers

Information

Microsoft PowerPoint - 7x24 Feb 2005.ppt

28 pages

Find more like this

Report File (DMCA)

Our content is added by our users. We aim to remove reported files within 1 working day. Please use this link to notify us:

Report this file as copyright or inappropriate

261116