Exhaust emissions and fuel economy improvements through thermal performance control in a novel three-way catalytic converter

Highly diluted, low temperature homogeneous charge compression ignition (HCCI) combustion leads to ultra-low levels of engine-out NOx emissions. A standard drive cycle, however, would require switches between HCCI and spark-ignited (SI) combustion modes. In this paper a methodology is introduced, investigating the fuel economy of such a multimode combustion concept in combination with a three-way catalytic converter (TWC). The TWC needs to exhibit unoccupied oxygen storage sites in order to show acceptable performance. But the lean exhaust gas during HCCI operation fills the oxygen storage and leads to a drop in NOx conversion efficiency. Eventually the levels of NOx become unacceptable and a mode switch to a fuel rich combustion mode is necessary in order to deplete the oxygen storage. The resulting lean-rich cycling leads to a penalty in fuel economy. In order to evaluate the impact of those penalties on fuel economy, a finite state model for combustion mode switches is combined with a longitudinal vehicle model and a phenomenological TWC model, focused on oxygen storage. The aftertreatment model is calibrated using combustion mode switch experiments from lean HCCI to rich spark-assisted HCCI and back. Fuel and emissions maps acquired in steady state experiments are used. Two depletion strategies are compared in terms of their influence on drive cycle fuel economy and NOx emissions.

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Tumble Flow Measurements Using Three Different Methods and Its Effects on Fuel Economy and Emissions

ASME 2006 Internal Combustion Engine Division Spring Technical Conference (ICES2006) ◽

10.1115/ices2006-1335 ◽

2006 ◽

Cited By ~ 3

Author(s):

Myoungjin Kim ◽

Sihun Lee ◽

Wootae Kim

Keyword(s):

Fuel Economy ◽

High Performance ◽

Gasoline Engine ◽

Exhaust Emissions ◽

Combustion Stability ◽

Lean Burn ◽

Flow Measurements ◽

Part Load ◽

Gasoline Engines ◽

Dynamometer Test

In-cylinder flows such as tumble and swirl have an important role on the engine combustion efficiencies and emission formations. In particular, the tumble flow, which is dominant in-cylinder flow in current high performance gasoline engines, has an important effect on the fuel consumptions and exhaust emissions under part load conditions. Therefore, it is important to know the effect of the tumble ratio on the part load performance and optimize the tumble ratio of a gasoline engine for better fuel economy and exhaust emissions. First step in optimizing a tumble flow is to measure a tumble ratio accurately. In this research the tumble flow was measured, compared and correlated using three different measurement methods: steady flow rig, 2-Dimensional PIV, and 3-Dimensional PTV. Engine dynamometer test was performed to find out the effect of the tumble ratio on the part load performance. Dynamometer test results of high tumble ratio engine showed faster combustion speed, retarded MBT timing, higher exhaust emissions, and a better lean burn combustion stability. Lean limit of the baseline engine was expanded from A/F=18:1 to A/F=21:1 by increasing a tumble ratio using MTV.

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Review of Performance and Emmissions Characteristics of Bio-Additive Fuel on SI Engine Fuelled by Biopetrol

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.773-774.430 ◽

2015 ◽

Vol 773-774 ◽

pp. 430-434

Author(s):

Azizul Mokhtar ◽

Nazrul Atan ◽

Najib Rahman ◽

Amir Khalid

Keyword(s):

Fuel Economy ◽

Fossil Fuels ◽

Review Paper ◽

Engine Performance ◽

Exhaust Emissions ◽

Spark Ignition Engine ◽

Si Engine ◽

New Approach ◽

Performance And Emission ◽

Performance And Emissions

Bio-additive is biodegradable and produces less air pollution thus significant for replacing the limited fossil fuels and reducing threats to the environment from exhaust emissions and global warming. Instead, the bio-additives can remarkably improve the fuel economy SI engine while operating on all kinds of fuel. Some of the bio-additive has the ability to reduce the total CO2 emission from internal petrol engine. This review paper focuses to determine a new approach in potential of bio-additives blends operating with bio-petrol on performance and emissions of spark ignition engine. It is shown that the variant in bio-additives blending ratio and engine operational condition are reduced engine-out emissions and increased efficiency. It seems that the bio-additives can increase the maximum cylinder combustion pressure, improve exhaust emissions and largely reduce the friction coefficient. The review concludes that the additives usage in bio-petrol is inseparable for the better engine performance and emission control and further research is needed to develop bio-petrol specific additives.

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Development of a Fuel Economy and Exhaust Emissions Test Method with HILS for Heavy-Duty HEVs

SAE International Journal of Engines ◽

10.4271/2008-01-1318 ◽

2008 ◽

Vol 1 (1) ◽

pp. 873-887 ◽

Cited By ~ 8

Author(s):

Kenji Morita ◽

Kazuki Shimamura ◽

Seiichi Yamaguchi ◽

Keiji Furumachi ◽

Nobuya Osaki ◽

...

Keyword(s):

Fuel Economy ◽

Exhaust Emissions ◽

Test Method ◽

Heavy Duty

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Toxic effects of exhaust emissions on spruce Picea abies and their reduction by the catalytic converter

Environmental Pollution Series A Ecological and Biological ◽

10.1016/0143-1471(86)90002-4 ◽

1986 ◽

Vol 42 (2) ◽

pp. 133-142 ◽

Cited By ~ 13

Author(s):

H. Kammerbauer ◽

H. Selinger ◽

R. Römmelt ◽

A. Ziegler Jöns ◽

D. Knoppik ◽

...

Keyword(s):

Picea Abies ◽

Catalytic Converter ◽

Exhaust Emissions ◽

Toxic Effects

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A Turbocharged Spark Ignition Engine with Low Exhaust Emissions and Improved Fuel Economy

10.4271/730633 ◽

1973 ◽

Cited By ~ 7

Author(s):

John F. Schweikert ◽

John H. Johnson

Keyword(s):

Fuel Economy ◽

Exhaust Emissions ◽

Spark Ignition ◽

Spark Ignition Engine

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Control of S.I. Engine Exhaust Emissions Using Non-Precious Catalyst (ZSM-5) Supported Bimetals and Noble Metals as Catalyst

ASME 2005 Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/ices2005-1025 ◽

2005 ◽

Author(s):

Bankim B. Ghosh ◽

Prokash Chandra Roy ◽

Mita Ghosh ◽

Paritosh Bhattacharya ◽

Rajsekhar Panua ◽

...

Keyword(s):

Noble Metal ◽

Noble Metals ◽

Bimetallic Catalyst ◽

Catalytic Converter ◽

Exhaust Emissions ◽

Metal Catalysts ◽

Oxides Of Nitrogen ◽

Noble Metal Catalysts ◽

Maximum Reduction ◽

Wide Range

Three Way Catalysts (TWC) are extensively used for simultaneous control of three principal automotive pollutants, namely carbon monoxide (CO), Oxides of nitrogen (NOx), and hydrocarbon (HC). Most of works on three way catalytic converter have been carried out with noble metals such as Platinum, Rhodium, and Iridium have been tried individually and in different combinations and proportions. Noble metal catalysts give very good performance of reduction of (NOx), CO and HC in the narrow range of stoichiometric Air Fuel ratio. Noble metals are costly and not abundantly available. These draw backs of the noble metal catalysts have inspired to search for the alternative catalysts, which will perform well over the wide range of A/F ratio and are economical and abundantly available. This paper discusses the processing of ZSM-5 to Cu-Ion- Exchanged ZSM-5, ZSM-5 supported Cu-Pt bimetallic catalyst and Cu-Rh bimetallic catalyst and placing them in a three staged converter to study the reduction efficiencies of exhaust emissions CO, NOx, and HC in a 800 cc Maruti S. I. Engine. The experiments are carried out at 1500 rpm, 17.6 A/F ratio, different catalyst bed temperatures and different engine loads 0%, 17.5%, 35%, 52.5%, and 70% of full load. The results achieved are the maximum reduction of CO 90% at 375 °C NOx 90% at 375 °C and HC 61% at 380 °C. The same engine was also run for Noble metal converter (NMC) (EURO-II) purchased from an authorized Maruti distributor and the maximum reduction achieved were CO 89% at 375° C, NOx 91% at 375° C, and HC 70% at 390° C comparable to Zeolite Catalytic Converter (ZCC).

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