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TRANSCRIPT
07/02/03 1
ARB ARB – Exhaust Emissions –– Exhaust Emissions – Tier 3Tier 3
Small Off-Road Engine Workshop – July 2, 2003
EMA / OPEIEngine Manufacturers Association / Outdoor Power Equipment Institute
Clean Air Act Committee
07/02/03 2
ARB ARB – Exhaust Emissions –– Exhaust Emissions – Tier 3Tier 3
Current production systems -- what do they achieve?
Southwest Research test program -- what does it demonstrate?
ARB’s current proposal -- what will it require for the air-cooled engine?
07/02/03 3
Small Off-Road Engine -Production Catalyst SystemsSmall Off-Road Engine -Production Catalyst Systems
International Catalyst System – B&S
– 20-30% HC+NOx Efficiency at 0 hrs
– 7-10% HC+NOx Efficiency at 125 hrs
– Marginal CO Conversion
07/02/03 4
Average Emissions - Quantum International Catalyst System -125 hr data ( 1.3 in Catalyst )
13.84
1.75
15.59
12.78
1.74
14.53
302294
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
HC (g/hp-hr) NOx (g/hp-hr) HC+NOx (g/hp-hr) CO (g/hp-hr)
HC
- N
Ox
- HC
+NO
x
0
25
50
75
100
125
150
175
200
225
250
275
300
325
350
SWC
O (g
/hp-
hr)
Engine Out Catalyst Out
3 %7 %
07/02/03 5
Small Off-Road Engine -Production Catalyst SystemsSmall Off-Road Engine -Production Catalyst Systems
Tecumseh TVM220
• 21.8 in3 Vertical L-Head• 15% HC+NOx Efficiency at 0 Hours
Tecumseh H35
• 9.5 in3 Horizontal L-Head• 29% HC+NOx Efficiency at 0 Hours
07/02/03 6
Southwest Research Test ProgramSouthwest Research Test Program
– Six engines equipped with high-load three-way converters
– Three engines equipped with non-integral systems
– Exhaust emissions and temperatures measured at 0 hours and after test stand operation
– No noise abatement or measurement
07/02/03 7
Muffler Skin Temperatures - SwRI B&S #1 ( 0 hrs )
675
622
539
471438
770
721
671
629 614
200
300
400
500
600
700
800
900
1000
100% Load - 9% 75% Load - 21% 50% Load - 31% 25% Load - 32% 10% Load - 7%
Te
mp
era
ture
(°F
)
B&S #1-STK B&S #1 Cat C
Cat C = 59% CO Efficiency = 133 g/hp-hr Ave Weighted Temp Increase => +133°F ( 25% ) from 540°F to 673°F
07/02/03 8
SwRI’s Catalyst System SwRI’s Catalyst System
07/02/03 9
Muffler Skin Temperatures Muffler Skin Temperatures
07/02/03 10
Temperature Measurements at SwRITemperature Measurements at SwRI
–Temperature measurements at SwRI are incomplete
–Temperature measurements at Briggs & Stratton indicate temperatures at 1150 F, not 770 F
–Southwest Research should conduct additional temperature measurements
07/02/03 11
SwRI – Honda GCV160SwRI – Honda GCV160
07/02/03 12
Muffler Skin Temperatures - SwRI SwRI Honda GVC160 ( 0 hrs )
571
508
441393
350
698
631
556505
449
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
100% Load - 9% 75% Load - 21% 50% Load - 31% 25% Load - 32% 10% Load - 7%
Te
mp
era
ture
(°F
)
Honda-STK Honda Cat J (remote)
Cat J = 63% CO Efficiency = 185 g/hp-hrAverage Weighted Temperature Increase => +116°F ( 26% ) from 445°F to 561°F
Note: Catalyst Remote Mounted
07/02/03 13
SwRI – Honda GCV160SwRI – Honda GCV160
07/02/03 14
SwRI –Honda GCV160SwRI –Honda GCV160
Heat is Dissipated from extension pipe and Muffler.
Heat is Dissipated from extension pipe and Muffler.
Catalyst has been moved away from engine.
Catalyst has been moved away from engine.
07/02/03 15
Conclusions -- SwRI Test ProgramConclusions -- SwRI Test Program
– High-load catalysts will require additional thermal management
• More hardware • More horsepower
– Other requirements related to after-treatment:• Noise: new, larger mufflers• Lean fueling: accelerator pumps, auto-choke
and warm-up feature – New base engine for walk-behind market in
California – New packaging/envelope challenges for
equipment manufacturers
07/02/03 16
Preliminary and Partial Cost EstimatesPreliminary and Partial Cost Estimates
–Approximately $60 for exhaust only (does not include evap)
–Cost estimates do not include:
• Warranty, testing or R&D
• OEM assembly and other costs
07/02/03 17
SummarySummary
–Can small engines achieve high conversion efficiency in the laboratory?
–Yes, but…
07/02/03 18
Summary Summary
Production for California will require complex changes at higher costs:
• Three-way high-load converters• Noise and thermal management• Major fuel system changes• New, larger base engine• New packaging solutions