76-5 AB
Evaluation of the Ethyl Lean Reactor System
Applied to a Dodge Coronet
November 1975
Technology Assessment and Evaluation Branch
Emission Control Technology Division
Office of Mobile Source Air Pollution Control
Environmental Protection Agency
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Background
For many years, Ethyl Corporation engineers have conducted research
into engine operation at lean air-fuel ratios. ;They were interested in
lean-mixture combustion because of the inherently low emissions and good
fuel economy that ar« possible without catalytic aftertreatment with a
properly .controlled lean engine. Some of their recent research efforts
have been directed toward a demonstration of the potential of lean-
mixture control techniques to meet emissions standards.
The Emission Control Technology Division (ECTD) recently tested
(Report 75-23) an Ethyl lean burn car equipped with a Turbulent Flow
Manifold (TFM). The system was installed on a BMW 2002. This vehicle
met the 1975 Federal emission,-standards and gave excellent fuel economy.
Ethyl has also done similar work on full sized vehicles. They have
achieved significant reductions in emissions on these vehicles and one
vehicle has completed mileage accumulation. ECTD, consistent with its
continuing interest in the evaluation of advanced automotive technology,
requested a vehicle for testing. Ethyl Corporation provided a Dodge
Coronet equipped with their TFM induction system and exhaust after-
treatment.
The Environmental Protection Agency receives information about many
systems which appear to offer potential for emissions reduction or
improvement in fuel economy compared to conventional engines and vehicles.
EPA's Emission Control Technology Division is interested in evaluating
all such systems, because of the obvious benefits to the Nation from the
identification of systems that can reduce emissions, improve economy, or
both. EPA invites developers of such systems to provide to the EPA
complete technical data on the system's principle of operation, together
with available test data on the system. In those cases in which review
by EPA technical staff suggests that the data available show promise for
the system, attempts are made to schedule tests at the EPA Emissions
Laboratory at .Ann Arbor, Michigan. The results of all such tests are
set forth in a series of Technology Assessment and Evaluation Reports,
of which this report is one.
The conclusions drawn from the EPA evaluation tests are of limited
applicability. A complete evaluation of the effectiveness of an emission
control system in achieving improvements on the different types of
vehicles that are in actual use requires a much larger sample of test
vehicles that is economically feasible in the evaluation test projects
conducted by EPA. For promising systems it is necessary that more
extensive test programs be carried out. ;
The conclusions from this EPA evaluation test can be considered to
be quantitatively valid only for the specific test car used. However,
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it is reasonable to extrapolate the results from the EPA test to other
types of vehicles in a directional or qualitative manner, i.e., to
suggest that similar results are likely to be achieved on other types of
vehicles.
Vehicle Description
The vehicle tested was a Dodge Coronet with a 360 cubic inch (5899
cc), V-8 engine and a 3-speed automatic transmission. The standard
induction system was replaced by an Ethyl TFM. Thermal reactors were
added for exhaust after-treatment. (The vehicle is described in detail
on the following page.)
The Ethyl Lean Reactor System (LRS) is a lean combustion system
with exhaust after-treatment. The intake manifold incorporates a number
of modifications to improve the homogeneity of the fuel-air mixture
without fuel economy or performance penalties. The manifold (Figure 1)
is a Dodge intake manifold modified to improve the quality of the fuel-
air mixture. The original carburetor was replaced by a unit with an
integral choke. Exhaust port liners were installed in the heads and lean
thermal reactor manifolds replaced the original exhaust manifolds.
The essential features of the TFM are the long mixing tube below
the primary venturi, the change of flow direction in the mixing box, and
the secondary venturi bypass. The long mixing tube allows the fuel-air
mixture downstream of the throttle to become more uniform. Changing the
flow direction increases turbulence which improves the mixture quality
and causes large fuel droplets to fall onto the mixing box floor, where
they are vaporized before reentering the stream. .The secondary flow
bypasses the mixing box in order to minimize pumping losses, thus
minimizing losses in volumetric efficiency.
Ethyl had previously installed their TFM on similar full sized
vehicles. Their test results showed that the major result of the
addition of port liners and thermal reactors was to lower hydrocarbons.
This permitted additional exhaust gas recirculation to achieve lower NOx
levels while simultaneously improving fuel economy by additional spark
advance.
In addition the vehicle was equipped with a particulate trap
(Figure 2) to remove lead particles from the vehicle exhaust. Large
particles are removed by a vortex inertia trap. Small particles are
agglomerated to become large particles which are then inertially separated.
EPA did not test the effectiveness of this particulate trap.
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TEST VEHICLE DESCRIPTION
Chassis model year/make - 1974 Dodge Coronet
Emission control system - Ethyl Lean Mixture System with
after-treatment
Engine
type i 4 stroke Otto Cycle, V-8
bore x stroke 4.00 x 3.58 in./101.6 x 90.9 mm
displacement . 360 cu in./5899 cc
compression ratio 8.6:1
maximum power @ rpm . n9t available
fuel metering single 4 barrel carburetor
fuel requirement . . regular leaded (per Ethyl Corporation)
tested with 100 RON leaded Indolene 30
Drive Train
transmission type ........ 3 speed automatic
final drive ratio 2.71:1
Chassis
type . . unitized.body/frame, front engine, rear
y.v . wheel drive J 6
tire size FR 78 x 14
curb weight ..... not available
inertia weight 4500 pounds
passenger capacity 6
Emission Control System
basic type lean combustion (mixture) system -
(Turbulent Flow Manifold)
exhaust gas recirculation
exhaust port liners
lean thermal reactor
particulate traps
distributor ... dual diaphram distributor advance unit
particulate trap tangential anchored - vortex trap
durability accumulated on system . 52,000 miles
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Primary Metering
System
Manifold
Runners
Mixing Tube
Heating Media
Conditioning Chamber
Chamber
Figure 1. Turbulent Flow Manifold
DUAL OUTLET
Figure 2. Tangential Anchor ed-V'Oy?tex
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Test Procedure
Exhaust emission's tests were conducted according to the 1975 Federal
Test Procedure ('75 FTP), described in the Federal Register of November
15, 1972 except that nb evaporative emissions tests were conducted.
Additional tests included the EPA Highway Cycle and steady state emissions
test. All tests were conducted using an inertia weight of 4500 pounds
(2041 kg) with a road load setting of 12.7 horsepower (9.5 kW) at 50
miles per hour (80.5 km/hr).
For this vehicle, Ethyl specified a regular gasoline, basing this
requirement on their own chassis dynamometer octane rating of 91 Research
Octane Number (RON) for leaded fuel and 93 RON for unleaded fuel. The
fuel used for the tests reported herein was Indolene 30, a standard
leaded (3.0 gm/gal) test fuel of 100 RON.
At the conclusion of the gaseous emissions tests the vehicle was
tested for sulfate emissions using the EPA sulfate procedures, which are
described in the Appendix.
Test Results
Exhaust emissions data, summarized below, showed that the Ethyl
test car, using the LRS, achieved the levels of the 1975-76 Federal and
California standards at 52,000 miles. Detailed test results appear
in the appendix to this report.
'75 FTP Composite Mass Emissions
grams per mile
(grams per kilometre)
average of 2 tests
HC
CO
NOx
.38 5.34 1.64
(.24) (3.32) (1.02)
1975-76 Federal Standards 1.5 15.0 3.1
1975-76 California Standards .9 9.0 2.0
On EPA Highway Cycle the results were:
Fuel Economy
(Fuel Consumption)
12.5 miles/gal
(18.8 litres/100 km)
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EPA Highway Cycle Mass Emissions
grams per mile
(grams per kilometre
HC
.08
(.05)
CO
average of 3 tests
Steady State fuel economy results were:
NOx
1.69 2.85
(-1.05) (1.77)
Fuel Economy
(Fuel Consumption)
21.4 miles/gal
(11.0 litres/100 km)
Speed mph (km/hr)
15 (24.1)
30 (48.3)
45 (72.4)
60 (96.6)
Fuel Economy
miles/gal
16.9
22.1
25.7
20.8
(Fuel Consumption)
litres/100 km
(13.9)
(10.6)
( 9.2)
(11.3)
Comparison of the test vehicle's combined city/highway fuel economy
with certification results for 1976 vehicles of the same inertia weight
(4500 pounds) showed that there was no fuel penalty.
Combined City/Highway
Ethyl Car 360 CID
Avg. 1975 4500 Ib. vehicle
Avg. 1976 4500 Ib. vehicle,
Avg. 1976 4500 Ib. vehicle,
Best 1976 4500 Ib. vehicle
Fuel Economy
mpg
15.4
14.6
15.7
14.2
16.1
Fuel Consumption
litres/100 km
(15.3)
(16.1)
(15.0)
(16.6)
(14.6)
* Similar engine and meeting 1976 California standards
MPG
combined
.55
MPG
.45
urban
MPG,
highway
In calculating city/highway combined fuel economy, the urban fuel
economy is weighted 55% and the highway fuel economy is weighted 45% to
account for the 55/45 ratio of urban to rural mileage accumulation.
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Emissions of HC, CO, NOx and sulfates are listed in the appendix.
For the sulfate tests the test fuel used was Indolene HO (clear) with a
sulfur content of .03 weight percent. The tests showed sulfate emissions
of about 7 mgpm which is slightly higher than those usually found for
other non-catalyst cars (5 mgpm or less). The first test showed sulfate
emissions over the FTP to be 17.6 mgpm, an exceptionally high level. It
should be noted that the car ran on leaded fuel before being sent to
EPA. Also, Ethyl reported the lead trap was full of lead salts, making
it possible that lead particulates from the trap could be emitted. It
is known that lead compounds interfere with the barium chloranilate
method used by EPA. It is therefore possible that this interference may
explain the higher than expected emissions of sulfates especially in the
initial tests, when more lead may have been emitted. In later tests
sulfate emissions were about 5 mgpm. Ethyl personnel analyzed two of
the EPA filters by the iodine titration method which is not affected by
lead compounds, and found about 20 micrograms of sulfate, which corresponds
to an emission rate of about 2 mgpm. The vehicle was tested with the
higher (10% of road load) used for air conditioned vehicles.
Vehicle driveability was acceptable and no problems were encountered.
There were no vehicle starting problems.
Conclusions
The Ethyl Dodge Coronet equipped with the Turbulent Flow Manifold
and Lean Reactor System met the emission levels required by 1975 Federal
and California standards at high mileage. There was no fuel economy
penalty for this technique relative to typical 1976 vehicles of the same
weight class.
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Table A-l
175 FTP Mass Emissions
grams per mile
Test Number
76-2405
76-2407
HC
Bag 1 Cold Transient
CO
C00
.96 11.35 730
.86 12.74 755
Fuel
NOx Economy
MPG
Bag 2 Hot Stabilized
Fuel
HC CO CO NOx Economy
MPG
Bag 3 Hot Transient
Fuel
HC CO C0? NOx Economy
MPG
2.21
1.97
11.8
11.4
.17
.17
3.09
3.11
723
751
1.52
1.35
12.2
11.7
.33
.42
4.67
4.41
579
598
1.89
1.49
15.1
14.6
Test Number
76-2405
76-2407
Table A-2
'75 FTP Composite Mass Emissions
grams per mile
HC
.38
.38
CO
5.22
5.45
co2
685
710
NOx
1.77
1.51
Fuel
Economy
MPG
12.8
12.3
00
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Table A-3
EPA Highway Cycle Mass Emissions
grams per mile
Test Number
76-2405
76-2458
76-2459
HC
.07
.08
.08
CO
1,71
1.69
1.68
co2
425
404
408
NOx
2.76
2.97
2.83
Fuel Economy MPG
20.7
21.8
21.6
Table A-4
Steady State Mass Emissions
grams per mile
Test Number
76-2406*
76-2408*
76-2409
76-2411
76-2412
76-2456
76-2413
76-2457
Speed MPH HC
Idle Neutral .07
Idle Drive .11
15 .23
30 .09
45 .29
45 .34
60 .06
60 .07
CO
.63
.73
2.67
1.34
3.15
3.41
2.15
2.15
co2
118
115
519
400
336
340
427
417
NOx
.04
.04
.24
.43
4.95
4.38
3.61
4.19
Fuel Economy MPG
.81
.79
16.9
22.1
25.9
25.6
20.6
21.1
* grams per minute/gallons per hour
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10
Ethyl Lean Reactor System
Procedures used to Measure Sulfate Emissions
1. The leaded fuel was drained from the test vehicle. The'vehicle was
refueled with Indolene HO gasoline containing 0.017% sulfur by weight.
The vehicle then returned to Ethyl for checkout thereby accumulating
about 100 miles on this fuel.
2. The vehicle returned and the fuel was drained from the vehicle. The
vehicle was refueled with Indolene HO gasoline doped to contain .030%
sulfur by weight. This fuel was used throughout the sulfate testing.
3. The vehicle was prepped by driving on the EPA vehicle preparation
route and over the LA-4 cycle. The road load was set to include an air
conditioning load.
4. The following sequence of test cycles was used to measure sulfate
emissions.
a) Cold start 75 FTP
b) Two hot sulfate cycles
c) One EPA Highway Driving Cycle
d) Two hot sulfate cycles.
This sequence was run on two consecutive days. Four additional
sulfate cycles were run after the last sequence.
5. The barium chloranilate procedure was used to determine the concentra-
tion of sulfates in the exhaust.
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Sulfate Procedure Emissions
Average Emissions
grams per mile
Test Type
75 FTP
Highway
Sulfate Cycle
HC
CO
COi
NOx
Fuel Economy
MPG
H2S04*
Conversion
.36
.06
.10
6.88
1.43
2.89
737
438
518
1.80
2.48
1.83
11.8
20.1
17.0
17.6
6.2
5.9
7.6
4.8
3.8
* Milligrams per mile
Mileage accumulation done with leaded fuel. Vehicle is equipped with a lead particulate trap.
EPA sulfate test procedures were developed for unleaded fuel. There may be lead interference
causing the results to be high.
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