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Viewing 1 to 30 of 98
Technical Paper
2009-04-20
Krishna Pradeep Chilumukuru, Rohith Arasappa, John H. Johnson, Jeffrey D. Naber
Active regeneration experiments were performed on a Cummins 2007 aftertreatment system by hydrocarbon dosing with injection of diesel fuel downstream of the turbocharger. The main objective was to characterize the thermal oxidation rate as a function of temperature and particulate matter (PM) loading of the catalyzed particulate filter (CPF). Partial regeneration tests were carried out to ensure measureable masses are retained in the CPF in order to model the oxidation kinetics. The CPF was subsequently re-loaded to determine the effects of partial regeneration during post-loading. A methodology for gathering particulate data for analysis and determination of thermal oxidation in a CPF system operating in the engine exhaust was developed. Durations of the active regeneration experiments were estimated using previous active regeneration work by Singh et al. 2006 [1] and were adjusted as the experiments progressed using a lumped oxidation model [2, 3]. Repeat experiments were conducted to evaluate the reproducibility of the experimental data.
Technical Paper
2009-04-20
Rayomand H. Dabhoiwala, John H. Johnson, Jeffrey D. Naber
Steady state loading characterization experiments were conducted at three different engine load conditions and rated speed on the cracked catalyzed particulate filter (CPF). The experiments were performed using a 10.8 L 2002 Cummins ISM-330 heavy duty diesel engine. The CPF underwent a ring off failure, commonly seen in particulate filters, due to high radial and axial temperature gradients. The filters were cracked during baking in an oven which was done to regenerate PM collected after every loading characterization experiment. Two different configurations i.e. with and without a diesel oxidation catalyst (DOC) upstream of the CPF were studied. The data were compared with that on an un-cracked CPF at similar engine conditions and configurations. Pressure drop, transient filtration efficiency by particle size and PM mass and gaseous emissions measurements were made during each experiment. Mass balance for the PM from the engine during the experiments was conducted in order to calculate the mass of PM oxidized.
Technical Paper
2009-04-20
Rohith Arasappa, Kiran C. Premchand, Krishna P. Chilumukuru, John H. Johnson, Jeffrey D. Naber, Song-Lin Yang
Active regeneration of a catalyzed particulate filter (CPF) is affected by a number of parameters specifically particulate matter loading and inlet temperature. The MTU 1-D 2-Layer CPF model [1] was used to analyze these effects on the pressure drop, oxidation and filtration characteristics of a CPF during active regeneration. In addition, modeling results for post loading experiments were analyzed to understand the difference between loading a clean filter as compared to a partially regenerated filter. Experimental data obtained with a production Cummins regenerative particulate filter for loading, active regenerations and post loading experiments were used to calibrate the MTU 1-D 2-Layer CPF model. The model predicted results are compared with the experimental data and were analyzed to understand the CPF characteristics during active regeneration at 1.1, 2.2 and 4.1 g/L particulate matter (PM) loading and CPF inlet temperatures of 525, 550 and 600°C. The activation energies for thermal oxidation reported in Chilumukuru et al. [2] were used and confirmed by these modeling results.
Technical Paper
2009-04-20
Kiran C. Premchand, John H. Johnson, Song-Lin Yang
A quasi-steady 1-dimensional computer model of a catalyzed particulate filter (CPF) capable of simulating active regeneration of the CPF via diesel fuel injection upstream of a diesel oxidation catalyst (DOC) or other means to increase the exhaust gas temperature has been developed. This model is capable of predicting gaseous species concentrations (HC's, CO, NO and NO2) and exhaust gas temperatures within and after the CPF, for given input values of gaseous species and PM concentrations before the CPF and other inlet variables such as time-varying temperature of the exhaust gas at the inlet of the CPF and volumetric flow rate of exhaust gas. Also, the model predicts the overall pressure drop across the CPF and its components and the filtration and oxidation processes of PM as functions of axial location in the CPF and time as well as secondary variables that are derived from the equations that are being solved for in the model (such as axial variation of PM cake layer thickness versus time).
Technical Paper
2008-04-14
Rayomand H. Dabhoiwala, John H. Johnson, Jeffrey D. Naber, Susan T. Bagley
A methodology to estimate the mass of particulate retained in a catalyzed particulate filter as a function of measured total pressure drop, volumetric flow rate, exhaust temperature, exhaust gas viscosity and cake and wall permeability applicable to real-time computation is discussed. This methodology is discussed from the view point of using it to indicate when to initiate active regeneration and as an On-Board Diagnostic tool to detect filter failures. Steady-state loading characterization experiments were conducted on a catalyzed diesel particulate filter (CPF) in a Johnson Matthey CCRT® (catalyzed continuously regenerating trap) system. The experiments were performed using a 10.8 L 2002 Cummins ISM heavy-duty diesel engine. Experiments were conducted at 20, 60 and 75% of full engine load (1120 Nm) and rated speed (2100 rpm) to measure the pressure drop, transient filtration efficiency, particulate mass balance, and gaseous emissions. During the research the CPF cracked with a characteristic ring-off failure.
Technical Paper
2008-04-14
Rayomand H. Dabhoiwala, John H. Johnson, Jeffrey D. Naber, Susan T. Bagley
Steady-state particulate loading experiments were conducted on an advanced production catalyzed particulate filter (CPF), both with and without a diesel oxidation catalyst (DOC). A heavy-duty diesel engine was used for this study with the experiments conducted at 20, 40, 60 and 75 % of full load (1120 Nm) at rated speed (2100 rpm). The data obtained from these experiments were used and are necessary for calibrating the MTU 1-D 2-Layer CPF model. These experimental and modeling results were compared to previous research conducted at MTU that used the same engine but an earlier development version of the combination of DOC and CPF. The motivation for the comparison of the two systems was to determine whether the reformulated production catalysts performed as good or better than the early development catalysts. The results were compared to understand the filtration and oxidation differences between the two DOC+CPF and the CPF-only aftertreatment systems. Comparisons of the pressure drop, filtration and passive oxidation performances are presented.
Technical Paper
2008-04-14
Saurabh Mathur, John H. Johnson, Jeffrey D. Naber, Susan T. Bagley, Anand S. Shende
A Cummins ISB 5.9 liter medium-duty engine with cooled EGR has been used to study an early extrusion of an advanced ceramic uncatalyzed diesel particulate filter (DPF). Data for the advanced ceramic material (ACM) and an uncatalyzed cordierite filter of similar dimensions are presented. Pressure drop data as a function of mass loadings (0, 4, and 6 grams of particulate matter (PM) per liter of filter volume) for various flow rate/temperature combinations (0.115 - 0.187 kg/sec and 240 - 375 °C) based upon loads of 15, 25, 40 and 60% of full engine load (684 N-m) at 2300 rpm are presented. The data obtained from these experiments were used to calibrate the MTU 1-D 2-Layer computer model developed previously at MTU. Clean wall permeability determined from the model calibration for the ACM was 5.0e-13 m2 as compared to 3.0e-13 m2 for cordierite. The calibrated model was then used to predict the pressure drop of the ACM and cordierite substrates for the same channel dimensions (width and thickness).
Technical Paper
2008-04-14
Maruthi Devarakonda, Gordon Parker, John H. Johnson, Vadim Strots, Shyam Santhanam
Model-based control strategies are important for meeting the dual objective of maximizing NOx reduction and minimizing NH3 slip in urea-SCR catalysts. To be implementable on the vehicle, the models should capture the essential behavior of the system, while not being computationally intensive. This paper discusses the adequacy of two different reduced order SCR catalyst models and compares their performance with a higher order model. The higher order model assumes that the catalyst has both diffusion and reaction kinetics, whereas the reduced order models contain only reaction kinetics. After describing each model, its parameter identification and model validation based on experiments on a Navistar I6 7.6L engine are presented. The adequacy of reduced order models is demonstrated by comparing the NO, NO2 and NH3 concentrations predicted by the models to their concentrations from the test data. It is observed that the 4 state model is a good representative of the physical system and is sufficient for model based control in urea-SCR aftertreatment systems.
Technical Paper
2008-04-14
Maruthi Devarakonda, Gordon Parker, John H. Johnson, Vadim Strots, Shyam Santhanam
In this paper, a model-based linear estimator and a non-linear control law for an Fe-zeolite urea-selective catalytic reduction (SCR) catalyst for heavy duty diesel engine applications is presented. The novel aspect of this work is that the relevant species, NO, NO2 and NH3 are estimated and controlled independently. The ability to target NH3 slip is important not only to minimize urea consumption, but also to reduce this unregulated emission. Being able to discriminate between NO and NO2 is important for two reasons. First, recent Fe-zeolite catalyst studies suggest that NOx reduction is highly favored by the NO 2 based reactions. Second, NO2 is more toxic than NO to both the environment and human health. The estimator and control law are based on a 4-state model of the urea-SCR plant. A linearized version of the model is used for state estimation while the full nonlinear model is used for control design. An experimentally validated, higher order simulation is used to evaluate the performance of the closed loop system.
Technical Paper
2007-04-16
Kiran C. Premchand, John H. Johnson, Song-Lin Yang, Antonio P. Triana, Kirby J. Baumgard
An experimental and modeling study was conducted to study the passive regeneration of a catalyzed particulate filter (CPF) by the oxidation of particulate matter (PM) via thermal and Nitrogen dioxide/temperature-assisted means. Emissions data in the exhaust of a John Deere 6.8 liter, turbocharged and after-cooled engine with a low-pressure loop EGR and a diesel oxidation catalyst (DOC) - catalyzed particulate filter (CPF) in the exhaust system was measured and used for this study. A series of experiments was conducted to evaluate the performance of the DOC, CPF and DOC+CPF configurations at various engine speeds and loads. Pressure drop across the devices, mass of PM deposited in the CPF at the end of loading, upstream and downstream gaseous and particulate emissions, and particle size distributions were measured at different times during the experiments to characterize the pressure drop and filtration efficiency of the DOC-CPF system at each engine load case as functions of loading time.
Technical Paper
2006-04-03
Antonio P. Triana, John H. Johnson, Song L. Yang, Kirby J. Baumgard
An experimental and computational study was performed to evaluate the performance of the CRT™ technology with an off-highway engine with a cooled low pressure loop EGR system. The MTU-Filter 1D DPF code predicts the particulate mass evolution (deposition and oxidation) in a diesel particulate filter (DPF) during simultaneous loading and during thermal and NO2-assisted regeneration conditions. It also predicts the pressure drop across the DPF, the flow and temperature fields, the solid filtration efficiency and the particle number distribution downstream of the DPF. A DOC model was also used to predict the NO2 upstream of the DPF. The DPF model was calibrated to experimental data at temperatures from 230°C to 550°C, and volumetric flow rates from 9 to 39 actual m3/min. Model predictions of the solid particulate mass deposited in the DPF after each loading and regeneration case were in agreement within +/-10g (or+/-10%) of experimental measurements at the majority of the engine operating conditions.
Technical Paper
2006-04-03
Hasan Mohammed, Venkata R. Lakkireddy, John H. Johnson, Susan T. Bagley
Modeling of diesel exhaust after-treatment devices is a valuable tool in the development and performance evaluation of these devices in a cost effective manner. Results from steady state loading experiments on a catalyzed particulate filter (CPF) in a Johnson Matthey CCRT®, performed with and without the upstream diesel oxidation catalyst (DOC) are described in this paper. The experiments were performed at 20, 40, 60 and 75% of full load (1120 Nm) at rated speed (2100 rpm) on a Cummins ISM 2002 heavy duty diesel engine. The data obtained were used to calibrate one dimensional (1-D) DOC and CPF models developed at Michigan Technological University (MTU). The 1-D 2-layer single channel CPF model helped evaluate the filtration and passive oxidation performance of the CPF. DOC modeling results of the pressure drop and gaseous emission oxidation performance using a previously developed model are also presented. The DOC modeling showed that HC, CO and NO oxidation kinetics can be represented by one set of ‘apparent’ kinetic parameters across the entire temperature and flow rate range encountered in this research.
Technical Paper
2006-04-03
Hasan Mohammed, Antonio P. Triana, Song-Lin Yang, John H. Johnson
A numerical model to simulate the filtration and regeneration performance of catalyzed diesel particulate filters (CPFs) was developed at Michigan Technological University (MTU). The mathematical formulation of the model and some results are described. The model is a single channel (inlet and outlet) representation of the flow while the thermal and catalytic regeneration framework is based on a 2-layer approach. The 2-layer model can simulate particulate matter (PM) oxidation by thermal and ‘catalytic’ means of oxidation with O2. Several improvements were made to this basic model and are described in this paper. A model to simulate PM oxidation by NO2/Temperature entering the particulate filter and oxidizing the PM in the two layers of the PM cake was developed. This model can be used to simulate the performance of filters with catalyst washcoats and uncatalyzed filters placed downstream of diesel oxidation catalysts (DOCs), as in the continuously regenerating traps, CRT's®. A sub-model that simulates the production of NO to NO2 in the washcoat of the CPF, and integrates with the NO2-PM oxidation model to simulate the higher oxidation rates (due to greater availability of NO2) in catalyzed continuously regenerating traps, CCRT's®, was developed.
Technical Paper
2006-04-03
Venkata R. Lakkireddy, Hasan Mohammed, John H. Johnson
The effect of a Johnson Matthey catalyzed continuously regenerating technology™ (CCRT®) filter on the particle size distribution in the raw exhaust from a 2002 Cummins ISM-2002 heavy duty diesel engine (HDDE) is reported at four loads. A CCRT® (henceforth called DOC-CPF) has a diesel oxidation catalyst (DOC) upstream (UP) of a catalyzed particulate filter (CPF). The particle size data were taken at three locations of UP DOC, downstream (DN) DOC and DN CPF in the raw exhaust in order to study the individual effect of the DOC and the CPF of the DOC-CPF on the particle size distribution. The four loads of 20, 40, 60 and 75% loads at rated speed were chosen for this study. Emissions measurements were made in the raw exhaust chosen to study the effect of nitrogen dioxide and temperature on particulate matter (PM) oxidation in the CPF at different engine conditions, exhaust and carbonaceous particulate matter (CPM) flow rates. This data was used for calibrating the MTU 1-D 2-layer filter model.
Technical Paper
2006-04-03
Venkata R. Lakkireddy, Hasan Mohammed, John H. Johnson, Susan T. Bagley
The objective of this research was to study the effects of a CCRT®, henceforth called Diesel Oxidation Catalyst - Catalyzed Particulate Filter (DOC-CPF) system on particulate and gaseous emissions from a heavy-duty diesel engine (HDDE) operated at Modes 11 and 9 of the old Environmental Protection Agency (EPA) 13-mode test cycle Emissions characterized included: total particulate matter (TPM) and components of carbonaceous solids (SOL), soluble organic fraction (SOF) and sulfates (SO4); vapor phase organics (XOC); gaseous emissions of total hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), nitric oxide (NO) and nitrogen dioxide (NO2), oxygen (O2) and carbon dioxide (CO2); and particle size distributions at normal dilution ratio (NDR) and higher dilution ratio (HDR). Significant reductions were observed for TPM and SOL (>90%), SOF (>80%) and XOC (>70%) across the DOC-CPF at both modes. The HC and NO reduction efficiencies across the DOC, CPF and the DOC-CPF were also significant at both modes.
Technical Paper
2006-04-03
Paramjot Singh, Abishek M. Thalagavara, Jeffrey D. Naber, John H. Johnson, Susan T. Bagley
Passive regeneration (oxidation of particulate matter without using an external energy source) of particulate filters in combination with active regeneration is necessary for low load engine operating conditions. For low load conditions, the exhaust gas temperatures are less than 250°C and the PM oxidation rate due to passive regeneration is less than the PM accumulation rate. The objective of this research was to experimentally investigate active regeneration of a catalyzed particulate filter (CPF) using diesel fuel injection in the exhaust gas after the turbocharger and before a diesel oxidation catalyst (DOC) and to collect data for extending the MTU 1-D 2-layer model to include the simulation of active regeneration. The engine used in this study was a 2002 Cummins ISM turbo charged 10.8 L heavy duty diesel engine with cooled EGR. The exhaust after-treatment system consisted of a Johnson Matthey DOC and CPF (a CCRT®). Steady-state loading experiments at 20% load at rated speed were performed for different times in order to achieve three particulate matter loadings of 1.1, 2.2 and 4.1 grams of particulate/liter of filter.
Book
2005-06-27
John H. Johnson
Emission and fuel economy regulations and standards are compelling manufacturers to build ultra-low emission vehicles. As a result, engineers must develop spark-ignition engines with integrated emission control systems that use reformulated low-sulfur fuel. Emission Control and Fuel Economy for Port and Direct Injected SI Engines is a collection of SAE technical papers that covers the fundamentals of gasoline direct injection (DI) engine emissions and fuel economy, design variable effects on HC emissions, and advanced emission control technology and modeling approaches. All papers contained in this book were selected by an accomplished expert as the best in the field; reprinted in their entirety, they present a pathway to integrated emission control systems that meet 2004-2009 EPA standards for light-duty vehicles.
Book
2005-06-27
John H. Johnson
Emission and fuel economy regulations and standards are compelling manufacturers to build ultra-low emission vehicles. As a result, engineers must develop spark-ignition engines with integrated emission control systems that use reformulated low-sulfur fuel. Combustion & Emission Control for SI Engines: Modeling and Experimental Studies is a collection of SAE technical papers that covers advanced emission measurements, combustion, exhaust after- treatment systems, fuel and lubricant effects on emissions, modeling of in-cylinder processes, and particle control and measurement. All papers contained in this book were selected by an accomplished expert as the best in the field; reprinted in their entirety, they present a pathway to integrated emission control systems that meet 2004-2009 EPA standards for light-duty vehicles.
Book
2005-06-17
John H. Johnson
This comprehensive set includes Emissions Control and Fuel Economy for Port and Direct Injected SI Engines and Combustion & Emission Control for SI Engines. Emissions Control and Fuel Economy for Port and Direct Injected SI Engines is a collection of 45 SAE technical papers that cover the fundamentals of gasoline direct injection (DI) engine emissions and fuel economy, design variable effects on HC emissions, and advanced emission control technology and modeling approaches. Combustion & Emission Control for SI Engines: Modeling and Experimental Studies is a collection of 45 SAE technical papers that covers advanced emission measurements, combustion, exhaust after-treatment systems, fuel and lubricant effects on emissions, modeling of in-cylinder processes, and particle control and measurement. Emissions Control and Fuel Economy for Port and Direct Injected SI Engines Combustion & Emission Control for SI Engines
Technical Paper
2005-04-11
Abishek M. Thalagavara, John H. Johnson, Susan T. Bagley, Anand S. Shende
The objective of this research was to study the effect of a catalyzed particulate filter (CPF) with a high loading of catalyst (50 gms/ft3) and ultra low sulfur fuel (ULSF -0.57 ppm of sulfur) on the emissions from a heavy duty diesel engine. The particulate emissions were measured using two different analytical methods, i.e., the gravimetric method and the thermal optical method (TOM). The results from the two different methods of analyses were compared. The experiments were performed at four different operating conditions chosen from the old Environmental Protection Agency (EPA) 13-mode test cycle. A 1995 Cummins M11 heavy-duty engine with manually controlled exhaust gas recirculation (EGR) was used to perform the emission characterization experiments. The emission characterization included total particulate matter (TPM), which is composed of the solids (SOL), soluble organic fractions (SOF) and sulfates (SO4) analyzed using the gravimetric method. The particulate emissions were also analyzed for total carbon (TC), elemental carbon (EC) and organic carbon (OC) using the TOM.
Technical Paper
2005-04-11
Brian J. Luptowski, Oner Arici, John H. Johnson, Gordon G. Parker
The increasing complexity of vehicle engine cooling systems results in additional system interactions. Design and evaluation of such systems and related interactions requires a fully coupled detailed engine and cooling system model. The Vehicle Engine Cooling System Simulation (VECSS) developed at Michigan Technological University was enhanced by linking with GT-POWER for the engine/cycle analysis model. Enhanced VECSS (E-VECSS) predicts the effects of cooling system performance on engine performance including accessory power and fuel conversion efficiency. Along with the engine cycle, modeled components include the engine manifolds, turbocharger, radiator, charge-air-cooler, engine oil circuit, oil cooler, cab heater, coolant pump, thermostat, and fan. This tool was then applied to develop and simulate an actively controlled electric cooling system for a 12.7 liter diesel engine.
Technical Paper
2005-04-11
Anand S. Shende, John H. Johnson, Song L. Yang, Susan T. Bagley, Abishek M. Thalagavara
A 1-D 2-layer model developed previously at MTU was used in this research to predict the pressure drop, filtration characteristics and various properties of the particulate filter and the particulate deposit layer. The model was calibrated and validated for this CPF with data obtained from steady state experiments conducted using a 1995 Cummins M11-330E heavy-duty diesel engine with manual EGR and using ULSF. The CPF used is a NGK filter having a cordierite substrate with NEX catalyst type formulation (54% porosity, 15.0 μm mean pore diameter and 50 gms/ft3 Pt). The filter was catalyzed using a wash coat process. The model was used to predict the pressure drop, particulate mass retained inside the CPF, particulate mass filtration efficiency and concentration downstream of the CPF with agreement between the experimental and simulated data. The model was also used to predict the clean substrate permeability, packing density of the particulate deposited inside the substrate, permeability and packing density of the particulate layer deposited on the substrate, activation energies and frequency factors for the thermal and catalytic oxidation path and the thickness of the particulate layer I, which is in contact with the catalyst.
Technical Paper
2005-04-11
Abishek M. Thalagavara, Anand S. Shende, John H. Johnson, Susan T. Bagley, S. L. Yang
A 1-D 2-layer model developed previously at MTU was used in this research to predict the pressure drop, filtration characteristics and various properties of the particulate filter and the particulate deposit layer. The model was used along with dilute emission data to characterize two catalyzed particulate filters (CPFs) having different catalyst loading and catalyst application processes. The model was calibrated and validated with data obtained from steady state experiments conducted using a 1995 Cummins M11-330E heavy-duty diesel engine with manual EGR with different fuels for the two different CPFs. The two different catalyzed particulate filters were CPF III (5 gms/ft3 Pt) and CPF V (50 gms/ft3 Pt). Both the CPFs had cordierite substrates with CPF III and CPF V had MEX and NEX catalyst type formulation respectively. The CPF III filter was catalyzed using a solution-impregnated process while the CPF V filter was catalyzed using a wash coat process. Experiments with the CPF III were conducted using conventional low sulfur fuel (CLSF) while ultra low sulfur fuel (ULSF) was used in conjunction with the CPF V.
Technical Paper
2005-04-11
Nishant Singh, John H. Johnson, Gordon G. Parker, Song-Lin Yang
Heavy-duty diesel engine particulate matter (PM) emissions must be reduced from 0.1 to 0.01 grams per brake horsepower-hour by 2007 due to EPA regulations [1]. A catalyzed particulate filter (CPF) is used to capture PM in the exhaust stream, but as PM accumulates in the CPF, exhaust flow is restricted resulting in reduced horsepower and increased fuel consumption. PM must therefore be burned off, referred to as CPF regeneration. Unfortunately, nominal exhaust temperatures are not always high enough to cause stable self-regeneration when needed. One promising method for active CPF regeneration is to inject fuel into the exhaust stream upstream of an oxidation catalytic converter (OCC). The chemical energy released during the oxidation of the fuel in the OCC raises the exhaust temperature and allows regeneration. This approach facilitates active control of the regeneration process so that the CPF can be operated in a sufficiently clean state to maintain engine performance and fuel economy.
Technical Paper
2003-10-27
Antonio P. Triana, John H. Johnson, Song L. Yang, Kirby J. Baumgard
A one-dimensional model simulating the oxidation of CO, HC, and NO was developed to predict the gaseous emissions downstream of a diesel oxidation catalyst (DOC). The model is based on the conservation of mass, species, and energy inside the DOC and draws on past research literature. Steady-state experiments covering a wide range of operating conditions (exhaust temperatures, flow rates and gaseous emissions) were performed, and the data were used to calibrate and validate the model. NO conversion efficiencies of 50% or higher were obtained at temperatures between 300°C and 350°C. CO conversion efficiencies of 85% or higher and HC conversion efficiencies of 75% or higher were found at every steady state condition above 200°C. The model agrees well with the experimental results at temperatures from 200°C to 500°C, and volumetric flow rates from 8 to 42 actual m3/min. The estimated activation energies and pre-exponential factors obtained from the model calibration are in good agreement with values reported in the literature.
Technical Paper
2003-03-03
James R. Warner, John H. Johnson, Susan T. Bagley, Cuong T. Huynh
A wide range of emissions were characterized from a heavy-duty diesel engine operated on conventional low sulfur (∼375 ppm) fuel, equipped with manually controlled EGR and a catalyzed particulate filter (CPF). The effect of the CPF and engine load was studied, along with a comparison of results between the gravimetric and thermal optical methods (TOM) for determining diesel particulate levels. Data were obtained from four of the EPA old 13 mode test cycle steady-state operating conditions, i.e., Modes 11, 10, 9, and 8 using a 1995 Cummins M11-330E engine with a Corning EX-80 cordierite particulate filter, coated with a platinum catalyst (5 g/ft3). Emission characterization results presented in this paper include: total particulate matter (TPM), comprised of solids (SOL), soluble organic fraction (SOF), and sulfates (SO4) that were determined gravimetrically; semi-volatile organic compounds (XOC), and total carbon (TC), comprised of elemental and organic carbon (EC and OC, respectively), that were obtained using the TOM.
Technical Paper
2003-03-03
Cuong T. Huynh, John H. Johnson, Song L. Yang, Susan T. Bagley, James R. Warner
A one-dimensional, two layer computational model was developed to predict the behavior of a clean and particulate-loaded catalyzed wall-flow diesel particulate filter (CPF). The model included the mechanisms of particle deposition inside the CPF porous wall and on the CPF wall surface, the exhaust flow field and temperature field inside the CPF, as well as the particulate catalytic oxidation mechanisms accounting for the catalyst-assisted particulate oxidation by the catalytic coating in addition to the conventional particulate thermal oxidation. The paper also develops the methodology for calibrating and validating the model with experimental data. Steady state loading experiments were performed to calibrate and validate the model. The experimental data were collected on a Corning EX-80 cordierite filter (100 cpi) with a loading of 5-g/ft3 Pt in the MEX catalyst type formulation using a 1995 Cummins M11-330E heavy-duty diesel engine with manual EGR and conventional low sulfur fuel (375 ppm sulfur).
Technical Paper
2003-03-03
Evdoxia A. Kladopoulou, Song L. Yang, John H. Johnson, Gordon G. Parker, Athanasios G. Konstandopoulos
A computational lumped parameter model (MTU-Filter-Lumped) was developed to describe the performance of diesel particulate filters (DPFs) during loading and regeneration processes. The model was formulated combining three major sub-models: a filtration model, a pressure drop model, and a mass and an energy balance equation for the total filter volume. The first two sub-models have been widely validated in the literature, while the third sub-model is introduced and combined with the first two sub-models in the present study. The three sub-models combined can give a full description of diesel particulate filter behavior during loading and regeneration processes, which was the objective of the present work. The total combined lumped parameter model was calibrated using experimental data from the literature covering a range of experimental conditions, including different catalytic regeneration means and engine operating conditions. The model predictions showed very good agreement with the experimental data in terms of pressure drop across the filter, mass retained in the filter, and filter temperature.
Book
2002-04-25
The focus of this book is on measurement techniques, fundamentals of NOx formation in the engine, exhaust gas recirculation (EGR), aftertreatment controls, fuel injection variables that lower NOx emissions, and fuel effects on NOx and particulate emissions. Diesel Nitrogen Oxide Emissions: Landmark Research 1995-2001 is based on extensive SAE literature from the past six years and is the first SAE Progress in Technology book published on the topic of measurement and control of diesel nitrogen oxide emissions. The papers in this book have been chosen as the most valuable on this topic.
Technical Paper
2002-03-04
Girish Janakiraman, John H. Johnson, Susan T. Bagley, James R. Warner, Cuong T. Huynh, Amjad Khan, David G. Leddy
A study was conducted to assess the effects of a water-diesel fuel emulsion with and without an oxidation catalytic converter (OCC) on steady-state heavy-duty diesel engine emissions. Two OCCs with different metal loading levels were used in this study. A 1988 Cummins L10-300 heavy-duty diesel engine was operated at the rated speed of 1900 rpm and at 75% and 25% load conditions (EPA modes 9 and 11 respectively) of the 13 mode steady-state test as well as at idle. Raw exhaust emissions' measurements included total hydrocarbons (HC), oxides of nitrogen (NOx) and nitric oxide (NO). Diluted exhaust measurements included total particulate matter (TPM) and its primary constituents, the soluble organic (SOF), sulfate (SO42-) and the carbonaceous solids (SOL) fractions. Vapor phase organic compounds (XOC) were also analyzed. The SOF and XOC samples were analyzed for selected polynuclear aromatic hydrocarbons (PAHs). The effect of the emulsified fuel without the OCC in the exhaust system was studied first.
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