Download - AMCA International Technical Seminar 2009
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AMCA InternationalTechnical Seminar 2009
Energy Efficiency Energy Efficiency Classification for FansClassification for Fans
John Cermak, Ph.D., P.Eng., M.Sc.Executive Vice President
ACME Engineering and Manufacturing Corp.
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The Air Movement and Control Association International The Air Movement and Control Association International (AMCA), has met the standards and requirements of the (AMCA), has met the standards and requirements of the Registered Continuing Education Providers Program. Registered Continuing Education Providers Program. Credit earned on completion of this program will be Credit earned on completion of this program will be reported to the RCEPP. A certificate of completion will be reported to the RCEPP. A certificate of completion will be issued to each participant. As such, it does not include issued to each participant. As such, it does not include content that may be deemed or construed to be an content that may be deemed or construed to be an approval or endorsement by NCEES or RCEPP.approval or endorsement by NCEES or RCEPP.
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Learning Objectives
• Learn about the current actions in fan industry leading to immediate and long term improvement in energy consumption by fans
• Understand the choices of the corner stones for building the AMCA Int’l initiative in ASHRAE and ISO
• Learn about importance of fan total pressure for finding energy savings
• Understand how fan selection impacts energy consumption of fans
• Understand how knowledge of the fan discharge energy contributes to successful fan selection from energy consumption point
• Learn about standardization of fan energy efficiency for better usage of energy by fans
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Fan Industry
Energy Consumption Challenge
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What is Happening?
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What is happening
ASHRAEASHRAE– 90.1 Standard (revision 2010)
– TC 5.1 Fans - ad hoc WG 90.1
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What is happening
AMCA InternationalAMCA International
– Mid-year and annual meetings 08– Fan Committee – SC for AMCA 205– AMCA Standard 205 “Energy
Efficiency Classification for Fans”
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What is happening
ISO/TC 117 ISO/TC 117 FansFans– WG 11 Fan Efficiency
– DIS 12759 Energy Classification
for fans
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What is happening
AMCA International AMCA International active in
ASHRAEASHRAE ANSIANSI ISO ISO
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Purpose
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Purpose
AMCA International AMCA International supporting
Legislative bodies
Regulatory bodies
in U.S.A.
as well as in other countries
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Purpose
Establishing ways and goals
to achieve significant energy
savings in usage of fans
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Purpose
Making the application of fans
fitting the energy consumption
goals without making it difficult
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Corner Stones
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Corner Stones
Fan energy efficiency based
on fan total pressure
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Corner Stones
Tool for regulative bodies
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Corner Stones
Support fan manufacturers’
effort to improve the energy
efficiency of their products
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Corner Stones
As much as possible keep one series in one efficiency grade
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Corner Stones
Fan peak total efficiency of a fan series is dependent on fan size
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Corner Stones
Defining areas of responsibility for:
Fan manufacturerFan manufacturer
Motor manufacturerMotor manufacturer
HVAC system designerHVAC system designer
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Fan Total Pressure
Why?
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Total or Static?
Fan creates pressures:
dynamic (velocity)
andand
static
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Total or Static
Both pressures are also specific specific energiesenergies a unit of flow exerted into the air by a fan
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Total or Static?
• Fan is a device to create air flow as its primaryprimary function
• The motionmotion of the air carries dynamicdynamic (velocity) energy
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Total or Static?
Fan total pressure Fan total pressure is sum of
dynamic (velocity) pressure
andand
static pressure
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Answer
For fan selection are needed at least two from the three fanpressures:
totaltotal and velocityvelocity staticstatic and velocityvelocity totaltotal and staticstatic
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Fan Selection
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Fan Selection
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Fan Selection
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Fan Selection
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Fan Selection
• Matching the pressure drop across the system against fan static pressure does notdoes not give the correct flow, fan size and power
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Fan Selection
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Fan Selection
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Using Fan Discharge Energy
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Using Discharge Energy
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Using Discharge Energy
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Using Discharge Energy
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Fan Characteristics
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Fan Energy Efficiency
• Fan is a device creating air flow and transferring energy transferring energy from the motor into the air
• Fan Total Pressure Fan Total Pressure is the total energy exerted into air by fan
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Fan Energy Efficiency
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Fan Energy Efficiency
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Fan Energy Efficiency
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Fan Energy Efficiency
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Fan Energy Efficiency
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Fan Energy Efficiency
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Fan energy Fan energy (total) efficiencyefficiency
FanFan total energy Energy from motormotor
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pTE
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pTE
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pTE
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The characteristic
of the fan energy
transformation
quality is
fanfan peak totalpeak total efficiency efficiency
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pTE
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Fan total efficiencyFan total efficiency
changes along the
fan pressure curve
significantly
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Fan size and pTE
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pTE
At constant tip speed the fanpTEpTE of a fan Series changes with the fan size
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pTE and Fan Size
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pTE and Fan Size
As a base fan
size was chosen
impeller size of
1000 mm (40”)1000 mm (40”)
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Fan Size Effect
The Size Effect Size Effect includes effects–Reynolds number
–changes in flow pattern
–impact of volumetric and mechanical losses
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Fan Size Effect
The Size Effect Size Effect includes effects–deviations from geometrical
similarity from size to size
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Fan Size Effect
The character of the Size EffectSize Effectchanges from one fan Series toanother
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Design of FEG System
FEG = Fan Efficiency Grade
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FEG System
20
30
40
50
60
70
80
90
0 100 200 300 400 500 600 700 800 900 1000
Op
tim
um
(p
ea
k)
fan
eff
icie
nc
y(%
)
Fan size (mm)
FEG90
FEG85
FEG80
FEG75
FEG71
FEG63
FEG67
FEG60
FEG56
FEG53
FEG50
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FEG System
• Grade labels in preferred numbers
e.g. FEG 8080, 71, 63 71, 63 etc.
• Layer thickness is Layer thickness is 6%6%
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Grade Label
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Grade Label
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Grade Label
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Grade Label
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Grade Label
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Grade Label
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Attached Conditions
Using these conditions would yield the fastest energy
savings
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Off Peak Load
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Part Load
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Part Load
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Part Load
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Part Load
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Part Load
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System Effects
Restrictions on usage of “system effects”
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Result
Defined Areas of Responsibility
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Areas of Responsibility
Fan manufacturerFan manufacturer Offers fans with the highest Offers fans with the highest pTEpTE
now at least FEG 67 later 71now at least FEG 67 later 71
and direct driven unitsand direct driven units
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Areas of Responsibility
Motor manufacturer Motor manufacturer Offer motors with highest pEffOffer motors with highest pEff
and smart unitsand smart units
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Areas of Responsibility
HVAC system desiHVAC system designer Optimizes use of the selectionOptimizes use of the selection of the fan and the motor incl.of the fan and the motor incl. drive package) drive package)
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Areas of Responsibility
What is missing?What is missing?
User of HVACUser of HVAC
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Questions?
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Thank You
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