Transcript 混合工质变浓度热泵系统的研究

Conserving Natural Resource Use in Buildings
Fan-Filter Testing The Results Are In
William Tschudi – [email protected]
Tengfang Xu – [email protected]
Lawrence Berkeley National Laboratory
http://hightech.lbl.gov
ASHRAE Annual Meeting
Long Beach, California
2007 ASHRAE Annual Meeting
Overview
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Background leading to testing fan-filter
units
Description of test configuration
Illustrative results
Use of the procedure
Possible next steps
Background
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Previous cleanroom
benchmarking
illustrated a large
variation in air
recirculation efficiency
Systems with fan-filter
units typically were
found to be less
efficient
DI Water Support
Process Water 5%
3%
Pumping
4%
Chillers and Pumps
21%
Nitrogen Plant
7%
Exhuast Fans
7%
Recirc and Make-up
Fans
19%
Process Tools
34%
Benchmarked Recirculation System
Efficiencies
11000
CFM / kW (higher is better)
10000
9000
Averages (cfm / kW)
FFU: 1664
Ducted: 1733
Pressurized Plenum: 5152
8000
7000
6000
5000
4000
3000
2000
1000
0
Fac. A
Fac. A Fac. B.1 Fac. B.1 Fac. B.2 Fac. B.2 Fac. C
Fac. D
Fac. E
Fac. E
Fac. F
Class 10 Class 100 Class 100 Class 100 Class 100 Class 100 Class 100 Class 10 Class 100 Class 100 Class 10
Press.
Press.
Ducted
FFU
Ducted
FFU
Press.
Ducted
FFU
Press.
Press.
Plen.
Plen.
Plen.
Plen.
Plen.
Fac. F
Class 10
Press.
Plen.
Fac. F
Fac. F
Class 10 Class 10k
Press.
Plen.
Background, con’t
In 2000, a Taiwanese Research Institute
evaluated fan-filter units – a wide range of
performance was noted
4'X2' FFU
40
FFU A
FFU B
FFU C
FFU D
FFU E
FFU F
FFU G
FFU H
FFU I-1
FFU I-2
FFU J
FFU K
FFU L
FFU M
FFU N
ERL FFU (AC)
ERL FFU (ACS)
ERL FFU (DC)
FFU P-1
FFU P-2
Electric Efficiency, %
35
30
25
20
15
10
5
0
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
Average Outlet Velocity, m/s
0.8
0.9
1.0
Background, con’t
We then began developing a standard test
procedure for fan-filter units to help get
“apples-to-apples” comparisons
The procedure is now available on our
website. It was used in the evaluation of
17 2’x4’ fan-filter units to “test” the
procedure and obtain performance
information
Test Configuration
Layout in test lab
Fan-filter Unit
Power meter
RPM meter
Airflow
Straightener
4
Pressure
Sensor
Airflow
Nozzle
Booster
Fan
Humidity
MD
Damper
F
Temperature
Configuration was dictated by space
available
Flow meter
An Accurate, Calibrated Flow Nozzle Determined Air Flow
Flow measurement:
Accuracy of a flow meter
(Nozzle) compared to a
flow hood was studied
 Flow meter gives
consistent, accurate
results
700
600
Nozzle (cfm)
 Discrepancies were
observed across units
between the two
methods
Measurement Comparison of Airflow Rates
800
500
400
y = 0.9267x
2
R = 0.9996
300
200
100
0
0
100
200
300
400
500
Flowhood (cfm)
600
700
800
Pressure Tap (Pitot Tube)
Pressures were determined at various places
throughout the system
Electric Power Monitoring Equip.
Available From Utility Tool Lending Library
Testing Considerations
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Air flow rate measurements
Pressure measurements
Power
Device calibration and uncertainties
Integrity of the testing system, e.g. leakage
Size of testing rig
Additional parameters, e.g., space/material cost
Ambient conditions
Sample Operating conditions
1000
900
800
Air Flow (scfm)
700
600
500
400
300
200
100
0
0
50
100
150
Pressure (Pa)
200
250
Unit with AC motor tested within its operating range
Operating conditions, cont.
1000
900
800
Air Flow (scfm)
700
600
500
400
300
200
100
0
0
50
100
150
Pressure (Pa)
200
250
Unit with ECM motor tested within its operating range
Total Electric Power Demand (W)
800
160
170
180
Airflow Rate (scfm)
Airflow cfm
700
600
500
400
20
40
60
80
100
120
140
Pressure (Pa)
Total electric power demand of the fan filter unit under
selected operable conditions: 20 Pa ≤ Dp ≤ 150 Pa, Q ≥ 9.9
m3/min (or 0.08 iwc ≤ Dp ≤ 0.6 iwc, Q ≥ 350 scfm)
Total Pressure Efficiency
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For FFUs with a multi-speed-drive, the total
electric power demand may be calculated as:
t =
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Q·Dp
C0 + C1·Dp + C2 ·Q+C11Dp2 + C12 ·Dp ·Q + C22 ·Q2
Dp is the pressure differential across the fan filter
unit
Q is the airflow rate across the unit under
standard atmospheric condition.
Ci,j (i, j = 0, 1, 2) is a coefficient developed
from experimental data through polynomial
regressions.
FFU power efficiency
FFU power efficiency (Et) is defined as the
airflow dynamic power divided by the total
electric power input to the FFU unit. The FFU
power efficiency includes electrical and
mechanical efficiency of the FFU unit taking
into account fan motors, fan design, housing,
etc.
Et = Pt Q / W
Pt = FFU pressure rise (Pa)
Q = air flow rate (m3/s)
W = electric power input to FFU (W)
FFU Total Pressure Efficiency
20
18
Q  POut, Total
16
Total Pressure Efficiency (%)
Power
14
12
10
1,600 RPM (Max)
8
1,500 RPM
1,300 RPM
6
1,100 RPM
4
900 RPM
2
0
0.0
0.1
0.2
0.3
Airflow Speed at Exit (m/s)
0.4
0.5
0.6
Total Pressure Efficiency
600
0.05
0.10
0.15
0.20
550
Airflow Rate (scfm)
Airflow cfm
500
450
400
350
20
40
60
80
100
120
Pressure (Pa)
Total pressure efficiency of the fan filter unit under selected
operable conditions: 20 Pa ≤ Dp ≤ 150 Pa, Q ≥ 9.9 m3/min (or
0.08 iwc ≤ Dp ≤ 0.6 iwc, Q ≥ 350 scfm)
Total Pressure Efficiency
800
0.00
0.05
0.10
0.15
0.20
700
Airflow Rate (scfm)
Airflow cfm
600
500
400
20
40
60
80
100
120
140
Pressure (Pa)
Total pressure efficiency of the fan filter unit under selected
operable conditions: 20 Pa ≤ Dp ≤ 150 Pa, Q ≥ 9.9 m3/min (or
0.08 iwc ≤ Dp ≤ 0.6 iwc, Q ≥ 350 scfm)
Efficiency Comparisons
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Variations in electric power and efficiency
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More than a factor of 10 difference for the same
unit across different operating conditions
Different units varied by 3 to 4 times for the
same operating condition
Variation patterns not obvious
Efficiency in the Range of Interest
Variation of FFU Efficiency
Total Pressure Efficiency
30%
25%
20%
15%
10%
5%
0%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Percentile Ranking: A higher percentile corresponds to higher total pressure efficiency
Xu, T. 2006 (9). Cleanrooms Magazine. Standard Development and Laboratory Testing of Fan Filter Units
Efficiency Comparisons
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ECM motors tended to be more efficient
however overall unit design influences
efficiency
Simple metrics not sufficient – depends upon
pressure and flow
How to Identify Efficient FFUs
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Implement Standard Lab Testing
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Standard test protocols to fully characterize
performance
Standard reporting
Determine expected range of operating
conditions
Review test results in range of expected
operation
Select unit considering energy performance
along with other desired features
Incentive Criteria Development
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Relative performance ranking system
 quantify the observed difference
 identify rebate-criteria.
Relative ranking scores
 examine the robustness of the suggested
initial rebate criteria.
Once an incentive criteria is set, units that
exceed that threshold can be selected
Recommended Practice
IEST RP CC036.1 – Testing Fan Filter Units
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Working draft of RP036.1 is being
developed
Interested parties are encouraged to
participate
Recommendations
Owners/designers - define requirements for
 Air recirculation
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Air change rate
Air flow rate
Cleanliness
Uniform air flow
System design
Pressure conditions
Recommendations
Procurement of fan-filter units
Define range of operating conditions
 Require testing in accordance with
standard test procedure
 Evaluate performance in the range of
interest
 Select based upon efficiency or
perform life cycle cost analysis
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Use of the standard test procedure
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A major semiconductor manufacturer adopted
standard, built a test rig, and required bidders
to provide units for testing as part of the
procurement process
An Asian company required FFU
manufacturers to provide test results during
the procurement process
A semiconductor manufacturer investigated
replacing aged FFUs with more efficient units
as determined by the test procedure
Reaction to the standard test
procedure
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Manufacturers are eager to know the
performance of their units - product
improvement is expected
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Recommended Practice (RP) CC036.1 is
planning on adopting the procedure
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A major utility is considering adding fan-filter
units to their incentive program
Possible next steps
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Recommended practice issued for use
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Optimize test rig (size)
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Testing of 4’x4’ units
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Utility incentive programs
Questions??