The Effect of Engine Exhaust Temperature Modulations on the Performance of Automotive Catalytic Converters

Exhaust Gas Temperature ◽

This paper presents a computational investigation of the effect of exhaust temperature modulations on an automotive catalytic converter. The objective is to develop a better fundamental understanding of the converter’s performance under transient driving conditions. Such an understanding will be beneficial in devising improved emission control methodologies. The study employs a single-channel based, one-dimensional, non-adiabatic model. The transient conditions are imposed by varying the exhaust gas temperature sinusoidally. The results show that temperature modulations cause a significant departure in the catalyst behavior from its steady behavior, and modulations have both favorable and harmful effects on pollutant conversion. The operating conditions and the modulating gas composition and flow rates (space velocity) have substantial influence on catalyst behavior.

The Effect of Engine Exhaust Temperature Modulations on the Performance of Automotive Catalytic Converters

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2747256 ◽

2007 ◽

Vol 130 (1) ◽

Cited By ~ 3

Author(s):

Tariq Shamim

Keyword(s):

Single Channel ◽

Catalytic Converter ◽

Space Velocity ◽

Operating Conditions ◽

Gas Temperature ◽

Engine Exhaust ◽

Exhaust Temperature ◽

Exhaust Gas Temperature ◽

This paper presents a computational investigation of the effect of exhaust temperature modulations on an automotive catalytic converter. The objective is to develop a better fundamental understanding of the converter’s performance under transient driving conditions. Such an understanding will be beneficial in devising improved emission control methodologies. The study employs a single-channel based, one-dimensional, nonadiabatic model. The transient conditions are imposed by varying the exhaust gas temperature sinusoidally. The results show that temperature modulations cause a significant departure in the catalyst behavior from its steady behavior, and modulations have both favorable and harmful effects on pollutant conversion. The operating conditions and the modulating gas composition and flow rates (space velocity) have substantial influence on catalyst behavior.

Design, Application, Performance and Emissions of Modern Internal Combustion Engine Systems and Components ◽

Dynamic Response of Automotive Catalytic Converters to Modulations in Engine Exhaust Compositions

10.1115/ices2003-0669 ◽

2003 ◽

Cited By ~ 1

Author(s):

Tariq Shamim

Keyword(s):

Single Channel ◽

Catalytic Converter ◽

Transient Behavior ◽

Operating Conditions ◽

Engine Exhaust ◽

Co Conversion ◽

Fundamental Understanding ◽

Conversion Performance ◽

This paper presents a computational investigation of the effect of composition modulations on an automotive catalytic converter. The objective is to develop a better fundamental understanding of the converter’s performance under actual driving conditions. Such an understanding will be beneficial in devising improved emission control methodologies by exploiting the catalyst transient behavior. The study employs a single-channel based, one-dimensional, non-adiabatic model. Two types of imposed transients (sinusoidal and step changes) are considered. The results show that composition modulations cause a significant departure in the catalyst behavior from its steady behavior, and modulations have both favorable and harmful effects on pollutant conversion. The departure is relatively significant for catalyst CO and HC conversion performance. The operating conditions and the modulating gas composition have substantial influence on catalyst behavior. Near stoichiometric condition, modulations of HC concentration have relatively greater effect and result in increased CO and HC conversions. Modulations of CO, on the other hand, result in a decrease of CO conversion. The effect of CO modulations on HC conversion is slightly positive. For the conditions studied, NO modulations generally do not result in any significant change in catalyst performance.

Dynamic behaviour of automotive catalytic converters subjected to variations in engine exhaust compositions

International Journal of Engine Research ◽

10.1243/146808705x27705 ◽

2005 ◽

Vol 6 (6) ◽

pp. 557-567 ◽

Cited By ~ 7

Author(s):

T Shamim

Keyword(s):

Dynamic Behaviour ◽

Single Channel ◽

Catalytic Converter ◽

Computational Investigation ◽

Engine Exhaust ◽

One Dimensional ◽

Transient Behaviour ◽

Fundamental Understanding ◽

ASME 2010 8th International Conference on Nanochannels, Microchannels, and Minichannels: Parts A and B ◽

Numerical Simulation of a Mini-Channel Three-Way Catalytic Converter

10.1115/fedsm-icnmm2010-30239 ◽

2010 ◽

Author(s):

M. H. Akbari ◽

R. Roohi ◽

S. A. Asaee

Keyword(s):

Conversion Efficiency ◽

Single Channel ◽

Heterogeneous Reaction ◽

Catalytic Converter ◽

Three Dimensional ◽

Space Velocity ◽

Kinetic Mechanism ◽

Operating Conditions ◽

Three Dimensional Model ◽

Different Temperatures

A three-dimensional model is developed to simulate the behavior of a single-channel three-way catalytic converter. The flow regime is assumed to be steady and laminar, and the channel walls are considered as isothermal. A multi-step, global heterogeneous reaction mechanism with 16 reactions and 11 species is used in this investigation to enhance the accuracy of the results. The chemical reactions are assumed to occur only on the reactor walls. The developed model is validated against available experimental data for stoichiometric operating conditions. The effect of the feed temperature on the conversion efficiency of the main pollutant components is studied. The light-off temperature for the stoichiometric A/F is found to be about 530 K for CO, NO and UHC, and 425 K for H2 conversion. The model is also applied to predict the effect of reactor length and inlet mixture space velocity on the conversion efficiency at two different temperatures. By using the same kinetics a well-stirred, unsteady model is also developed to identify the sensitivity of the multi-step kinetic mechanism to the mixture composition. The effect of mole fraction variation of each species on the conversion of other mixture components is investigated.

Volume 2: Emissions Control Systems; Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development ◽

Effect of Fuel Injection Strategy on DPF Regeneration in Single Cylinder Diesel Engine

10.1115/icef2015-1140 ◽

2015 ◽

Cited By ~ 1

Author(s):

Sungjun Yoon ◽

Hongsuk Kim ◽

Daesik Kim ◽

Sungwook Park

Keyword(s):

Diesel Engine ◽

Fuel Injection ◽

Operating Conditions ◽

Experimental Results ◽

Exhaust Gas ◽

Post Injection ◽

Gas Temperature ◽

Injection Strategy ◽

Dpf Regeneration ◽

Stringent emission regulations (e.g., Euro-6) force automotive manufacturers to equip DPF (diesel particulate filter) on diesel cars. Generally, post injection is used as a method to regenerate DPF. However, it is known that post injection deteriorates specific fuel consumption and causes oil dilution for some operating conditions. Thus, an injection strategy for regeneration becomes one of key technologies for diesel powertrain equipped with a DPF. This paper presents correlations between fuel injection strategy and exhaust gas temperature for DPF regeneration. Experimental apparatus consists of a single cylinder diesel engine, a DC dynamometer, an emission test bench, and an engine control system. In the present study, post injection timing covers from 40 deg aTDC to 110 deg aTDC and double post injection was considered. In addition, effects of injection pressures were investigated. The engine load was varied from low-load to mid-load and fuel amount of post injection was increased up to 10mg/stk. Oil dilution during fuel injection and combustion processes were estimated by diesel loss measured by comparing two global equivalences ratios; one is measured from Lambda sensor installed at exhaust port, the other one is estimated from intake air mass and injected fuel mass. In the present study, the differences in global equivalence ratios were mainly caused from oil dilution during post injection. The experimental results of the present study suggest an optimal engine operating conditions including fuel injection strategy to get appropriate exhaust gas temperature for DPF regeneration. Experimental results of exhaust gas temperature distributions for various engine operating conditions were summarized. In addition, it was revealed that amounts of oil dilution were reduced by splitting post injection (i.e., double post injection). Effects of injection pressure on exhaust gas temperature were dependent on combustion phasing and injection strategies.

Effect of the Fuel Injection Strategy on Diesel Particulate Filter Regeneration in a Single-Cylinder Diesel Engine

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4033161 ◽

2016 ◽

Vol 138 (10) ◽

Cited By ~ 5

Author(s):

Sungjun Yoon ◽

Hongsuk Kim ◽

Daesik Kim ◽

Sungwook Park

Keyword(s):

Fuel Injection ◽

Injection Pressure ◽

Operating Conditions ◽

Particulate Filter ◽

Exhaust Gas ◽

Gas Temperature ◽

Diesel Particulate ◽

Injection Strategy ◽

Dpf Regeneration ◽

Stringent emission regulations (e.g., Euro-6) have forced automotive manufacturers to equip a diesel particulate filter (DPF) on diesel cars. Generally, postinjection is used as a method to regenerate the DPF. However, it is known that postinjection deteriorates the specific fuel consumption and causes oil dilution for some operating conditions. Thus, an injection strategy for regeneration is one of the key technologies for diesel powertrains equipped with a DPF. This paper presents correlations between the fuel injection strategy and exhaust gas temperature for DPF regeneration. The experimental apparatus consists of a single-cylinder diesel engine, a DC dynamometer, an emission test bench, and an engine control system. In the present study, the postinjection timing was in the range of 40 deg aTDC to 110 deg aTDC and double postinjection was considered. In addition, the effects of the injection pressure were investigated. The engine load was varied among low load to midload conditions, and the amount of fuel of postinjection was increased up to 10 mg/stk. The oil dilution during the fuel injection and combustion processes was estimated by the diesel loss measured by comparing two global equivalences ratios: one measured from a lambda sensor installed at the exhaust port and one estimated from the intake air mass and injected fuel mass. In the present study, the differences of the global equivalence ratios were mainly caused by the oil dilution during postinjection. The experimental results of the present study suggest optimal engine operating conditions including the fuel injection strategy to obtain an appropriate exhaust gas temperature for DPF regeneration. The experimental results of the exhaust gas temperature distributions for various engine operating conditions are discussed. In addition, it was revealed that the amount of oil dilution was reduced by splitting the postinjection (i.e., double postinjection). The effects of the injection pressure on the exhaust gas temperature were dependent on the combustion phasing and injection strategies.

Preliminary Thermal Analyses on Diesel Converter Overheating

ASME 2004 Internal Combustion Engine Division Fall Technical Conference ◽

10.1115/icef2004-0890 ◽

2004 ◽

Author(s):

Jun Zuo ◽

Meiping Wang ◽

Graham T. Reader ◽

Ming Zheng

Keyword(s):

Oxygen Concentration ◽

Active Flow Control ◽

Thermal Analyses ◽

Gas Temperature ◽

Engine Exhaust ◽

Transient Model ◽

Exhaust Temperature ◽

Combustible Gas ◽

Soot Loading ◽

Reduce Emissions

The use of oxidation catalytic converters (OCC) in Diesel engines has proved to be an effective method to reduce emissions of total hydrocarbons (THC), carbon monoxide (CO), and the soluble organic fractions (SOF) of particulate matter (PM). However, the exothermal reaction effected by the oxidation of THC, CO, and especially the soot accumulated in the converters impose a risk of catalytic flow bed overheating that subsequently results in catalyst failure and may cause safety concerns. This paper presents a one-dimensional transient model that uses an energy balance method to analyze the overheating scenario when considering combustible gas reaction, clogged soot burning, and active flow control for a number of Diesel aftertreatment devices. The monolith temperature profiles were simulated by varying the exhaust gas temperature, oxygen concentration, and flow rate. Simulation results indicated that the potential of overheating elevates with increases in combustible gas concentration, soot loading, oxygen concentration, and engine exhaust temperature. The impacts of active control, such as flow reversal control, on converter overheating have also been investigated therein.

Modeling of Three-Way Catalyst Dynamics for a Compressed Natural Gas Engine during Lean–Rich Transitions

Applied Sciences ◽

10.3390/app9214610 ◽

2019 ◽

Vol 9 (21) ◽

pp. 4610 ◽

Cited By ~ 3

Author(s):

Dario Di Maio ◽

Carlo Beatrice ◽

Valentina Fraioli ◽

Pierpaolo Napolitano ◽

Stefano Golini ◽

...

Keyword(s):

Steady State ◽

Natural Gas ◽

Catalytic Converter ◽

Operating Conditions ◽

Oxygen Storage ◽

Continuous Control ◽

Engine Exhaust ◽

Compressed Natural Gas ◽

The Impact ◽

Three Way Catalyst

The main objective of the present research activity was to investigate the effect of very fast composition transitions of the engine exhaust typical in real-world driving operating conditions, as fuel cutoff phases or engine misfire, on the aftertreatment devices, which are generally very sensitive to these changes. This phenomenon is particularly evident when dealing with engines powered by natural gas, which requires the use of a three-way catalyst (TWC). Indeed, some deviations from the stoichiometric lambda value can interfere with the catalytic converter efficiency. In this work, a numerical “quasi-steady” model was developed to simulate the chemical and transport phenomena of a specific TWC for a compressed natural gas (CNG) heavy-duty engine. A dedicated experimental campaign was performed in order to evaluate the catalyst response to a defined λ variation pattern of the engine exhaust stream, thus providing the data necessary for the numerical model validation. Tests were carried out to reproduce oxygen storage phenomena that make catalyst behavior different from the classic steady-state operating conditions. A surface reaction kinetic mechanism concerning CH4, CO, H2, oxidation and NO reduction has been appropriately calibrated at different λ values with a step-by-step procedure, both in steady-state conditions of the engine work plan and during transient conditions, through cyclical and consecutive transitions of variable frequency between rich and lean phases. The activity also includes a proper calibration of the reactions involving cerium inside the catalyst in order to reproduce oxygen storage and release dynamics. Sensitivity analysis and continuous control of the reaction rate allowed evaluating the impact of each of them on the exhaust composition in several operating conditions. The proposed model predicts tailpipe conversion/formation of the main chemical species, starting from experimental engine-out data, and provides a useful tool to evaluate the catalyst’s performance.

Application of the Regularization Chaos Prediction Model in Aero-Engine Performance Parameters

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.424-425.347 ◽

2012 ◽

Vol 424-425 ◽

pp. 347-351 ◽

Cited By ~ 1

Author(s):

Yong Sheng Shi ◽

Jun Jie Yue ◽

Yun Xue Song

Keyword(s):

Prediction Model ◽

Simulation Analysis ◽

Search Algorithm ◽

Engine Performance ◽

Forecasting Model ◽

Exhaust Gas ◽

Gas Temperature ◽

Engine Exhaust ◽

Aero Engine ◽

Based on the research of complexity and non-linearity of aero-engine exhaust gas temperature (EGT) system, a regularization chaotic prediction model was proposed to build short time forecasting model of EGT. In this paper, in order to gain the best parameter to improve the accuracy of the forecasting model, a simple search algorithm arithmetic was adopted. The simulation analysis shows that the proposed forecasting model obviously exceeded the traditional chaotic forecasting model on prediction accuracy. Therefore, this arithmetic is efficient and feasible for a short-term prediction of aero-engine exhaust gas temperature

Study And Evaluation of Injection Timing of CIDI Engine Injection Pump Using Alternate Fuel i.e Biodiesel Fuel

SAMRIDDHI A Journal of Physical Sciences Engineering and Technology ◽

10.18090/samriddhi.v8i1.11407 ◽

2016 ◽

Vol 8 (01) ◽

pp. 11-19

Author(s):

P. K. Singh ◽

Rohit K. Shrivastava ◽

K. G. Sinha

Keyword(s):

Diesel Engine ◽

Direct Injection ◽

Biodiesel Fuel ◽

Injection Timing ◽

Gas Temperature ◽

Engine Exhaust ◽

Brake Thermal Efficiency ◽

Injection Pump ◽

Alternate Fuel ◽

In this investigation an experimental study of the effects of FIP injection timing on Specific Fuel Consumption(SFC), Brake Thermal Efficiency(BTE), Engine Exhaust Gas Temperature(EEGT), CO, HC, NOX and Smoke of “Kirloskar- 6R1080TA, 6-CylinderInline, Direct Injection, Turbocharged Intercooled, 191 hp Diesel Engine” has been conducted. Injection Timing retardation method has been utilised to reduce SFC, EEGT, CO, HC, NOX, Smoke and increase BTE of Kirloskar-6R1080TA Diesel Engine. The Kirloskar 6R1080TA engine has been tested for six different injection timings (23°, 21°, 20°, 19°, 18° and 17° CA BTC) at same engine speeds and load conditions. The SFC,EEGT, CO, HC, NOX and Smoke of engine are approximately higher and BTE lower for injection timings at 23°, 21°, 20°, 18° and 17° CA BTC than 19° CA BTC at same speed and load. The results are showing that SFC,EEGT,CO,HC,NOX and Smoke are approximately reduces and BTE increases by reducing injection timing from 23° CA BTC to 19° CA BTC. Optimum FIP injection timing for Kirloskar 6R1080TA engine has been achieved at 19° CA BTC.