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Catalyzed Particulate Filter Passive Oxidation Study with ULSD and Biodiesel Blended Fuel

2012-06-18
A 2007 Cummins ISL 8.9L direct-injection common rail diesel engine rated at 272 kW (365 hp) was used to load the filter to 2.2 g/L and passively oxidize particulate matter (PM) within a 2007 OEM aftertreatment system consisting of a diesel oxidation catalyst (DOC) and catalyzed particulate filter (CPF). Having a better understanding of the passive NO2 oxidation kinetics of PM within the CPF allows for reducing the frequency of active regenerations (hydrocarbon injection) and the associated fuel penalties. Being able to model the passive oxidation of accumulated PM in the CPF is critical to creating accurate state estimation strategies. The MTU 1-D CPF model will be used to simulate data collected from this study to examine differences in the PM oxidation kinetics when soy methyl ester (SME) biodiesel is used as the source of fuel for the engine.
Technical Paper

Pressure-Swirl Atomization in the Near Field

1999-03-01
1999-01-0496
To model sprays from pressure-swirl atomizers, the connection between the injector and the downstream spray must be considered. A new model for pressure-swirl atomizers is presented which assumes little knowledge of the internal details of the injector, but instead uses available observations of external spray characteristics. First, a correlation for the exit velocity at the injector exit is used to define the liquid film thickness. Next, the film must be modeled as it becomes a thin, liquid sheet and breaks up, forming ligaments and droplets. A linearized instability analysis of the breakup of a viscous, liquid sheet is used as part of the spray boundary condition. The spray angle is estimated from spray photographs and patternator data. A mass averaged spray angle is calculated from the patternator data and used in some of the calculations.
Technical Paper

Vibrational and Sound Radiation Properties of a Double Layered Diesel Engine Gear Cover

1999-05-17
1999-01-1773
The introduction of a thin fluid layer between two layers of sheet metal offers a highly effective and economical alternative to the use of constrained viscoelastic damping layers in sheet metal structures. A diesel engine gear cover, which is constructed of two sheet metal sections spot welded together, takes advantage of fluid layer damping to produce superior vibration and sound radiation performance. In this paper, the bending of a double layered plate coupled through a thin fluid layer is modeled using a traveling wave approach which results in a impedance function that can be used to assess the vibration and sound radiation performance of practical double layered plate structures. Guided by this model, the influence of fluid layer thickness and inside-to-outside sheet thickness is studied.
Technical Paper

Application of Indirect Force Estimation Techniques to the Automotive Transfer Case

1999-05-17
1999-01-1764
In the NVH design optimization of automotive structures, the spectral properties of dynamic forces transmitted from rotating machinery to its housing is of primary interest. This paper describes the application of an indirect dynamic force estimation technique, more commonly known as transfer path analysis, to an operational transfer case. Through the implementation of an inverse transfer matrix technique, dynamic forces transmitted to a transfer case housing are estimated at a discrete number of locations. This paper describes the experimental and analytical methodology employed for dynamic force estimation as well as statistical techniques for solution optimization. Good correlation is shown to exist between frequencies of known physical phenomena and estimated dynamic forces for a total of nine (9) operational variations of transfer case speed and torque.
Technical Paper

Extraction/Filtration of Transients Embedded in Stationary Signals Using Wavelets; Focus on Extraction of Frequency Response Functions

1999-05-17
1999-01-1824
Recent trends in signal processing have led to the discovery and implementation of wavelets as tools of many different applications. This paper focuses on their use as a tool for transient extraction. From the Discrete Wavelet Transform (DWT), specific coefficients are picked using a coherence-based criterion. These coefficients are then taken back to the time domain as the extracted transient. If the extracted transient is a response from a measured input, then a frequency response function can be formulated.
Technical Paper

Measurement of Dynamic Properties of Automotive Shock Absorbers for NVH

1999-05-17
1999-01-1840
This paper describes a project on the dynamic characterization of automotive shock absorbers. The objective was to develop a new testing and analysis methodology for obtaining equivalent linear stiffness and damping of the shock absorbers for use in CAE-NVH low- to- mid frequency chassis models. Previous studies using an elastomer test machine proved unsuitable for testing shocks in the mid-to-high frequency range where the typical road input displacements fall within the noise floor of the elastomer machine. Hence, in this project, an electrodynamic shaker was used for exciting the shock absorbers under displacements less than 0.05 mm up to 500 Hz. Furthermore, instead of the swept sine technique, actual road data were used to excite the shocks. Equivalent linear spring-damper models were developed based on least-squares curve-fitting of the test data.
Technical Paper

Development of an FRF Based Order Tracking Technique to Separate Close and/or Crossing Orders

1999-05-17
1999-01-1828
A frequency domain order tracking method is developed that is able to separate both close and crossing orders. This method is based upon the multiple input H1 FRF estimator. The method can use either the actual tachometer pulse train or a simulated chirp function as an assumed input to formulate the FRFs which are actually order tracks. The advantages and disadvantages of using each type of assumed input are discussed. The performance of this method in both simple and complex order tracking cases is evaluated. Analytical datasets are used to evaluate the performance of these order tracking methods under a variety of operating conditions which include close orders. Finally, this paper will develop the necessary derivation to show the analytical relationship between the Time Variant Discrete Fourier Transform (TVDFT) and the FRF based techniques, one being an order domain method and one being a frequency domain method.
Technical Paper

Post-Processing Analysis of Large Channel Count Order Track Tests and Estimation of Linearly Independent Operating Shapes

1999-05-17
1999-01-1827
Large channel count data acquisition systems have seen increasing use in the acquisition and analysis of rotating machinery, these systems have the ability to generate very large amounts of data for analysis. The most common operating measurement made on powertrains or automobiles on the road or on dynamometers has become the order track measurement. Order tracking analysis can generate a very large amount of information that must be analyzed, both due to the number of channels and orders tracked. Analysis methods to efficiently analyze large numbers of Frequency Response Function (FRF) measurements have been developed and used over the last 20 years in many troubleshooting applications. This paper develops applications for several FRF based analysis methods as applied for efficient analysis of large amounts of order track data.
Technical Paper

Reduction of the Environmental Impact of Essential Manufacturing Processes

1999-03-01
1999-01-0355
The drive of Design for the Environment is to reduce the environmental impact of both design and manufacturing processes. The most frequent method recommended is to substitute better materials and processes. However, there are processes that will continue to have undesirable environmental impacts due to the lack of knowledge of better methods. These processes are critical to manufacturing of products and can not be eliminated. All possible substitutions appear to have worse impacts. This paper explores modeling these processes and imposing a control method which permits an improvement of the environmental impact.
Technical Paper

The Vehicle Engine Cooling System Simulation Part 1 - Model Development

1999-03-01
1999-01-0240
The Vehicle Engine Cooling System Simulation (VECSS) computer code has been developed at the Michigan Technological University to simulate the thermal response of the cooling system of an on-highway heavy duty diesel powered truck under steady and transient operation. This code includes an engine cycle analysis program along with various components for the four main fluid circuits for cooling air, cooling water, cooling oil, and intake air, all evaluated simultaneously. The code predicts the operation of the response of the cooling circuit, oil circuit, and the engine compartment air flow when the VECSS is operated using driving cycle data of vehicle speed, engine speed, and fuel flow rate for a given ambient temperature, pressure and relative humidity.
Technical Paper

Threshold Level as an Index of Squeak and Rattle Performance

1999-05-17
1999-01-1730
A practical approach for evaluating and validating global system designs for Squeak and Rattle performance is proposed. Using simple slip and rattle models, actual sound and vibration data, and the fundamentals of audiological perception, analysis tools adapted from Chaos Theory are used to establish threshold levels of performance and identify system characteristics which are significant contributors to Squeak and Rattle. Focus on system design is maintained by using a simple rattle noise indicator and relating rattle events to levels of dynamic motion (acceleration, velocity, etc.). The threshold level is defined as the level of acceleration at which the system moves from a non-rattling state to a rattling state. The approach is demonstrated with a simple analytical model applied to an experimental structure under dynamic load.
Technical Paper

Material Damping Properties: A Comparison of Laboratory Test Methods and the Relationship to In-Vehicle Performance

2001-04-30
2001-01-1466
This paper presents the damping effectiveness of free-layer damping materials through standard Oberst bar testing, solid plate excitation (RTC3) testing, and prediction through numerical schemes. The main objective is to compare damping results from various industry test methods to performance in an automotive body structure. Existing literature on laboratory and vehicle testing of free-layer viscoelastic damping materials has received significant attention in recent history. This has created considerable confusion regarding the appropriateness of different test methods to measure material properties for damping materials/treatments used in vehicles. The ability to use the material properties calculated in these tests in vehicle CAE models has not been extensively examined. Existing literature regarding theory and testing for different industry standard damping measurement techniques is discussed.
Technical Paper

The Effects of Different Input Excitation on the Dynamic Characterization of an Automotive Shock Absorber

2001-04-30
2001-01-1442
This paper deals with the dynamic characterization of an automotive shock absorber, a continuation of an earlier work [1]. The objective of this on-going research is to develop a testing and analysis methodology for obtaining dynamic properties of automotive shock absorbers for use in CAE-NVH low-to-mid frequency chassis models. First, the effects of temperature and nominal length on the stiffness and damping of the shock absorber are studied and their importance in the development of a standard test method discussed. The effects of different types of input excitation on the dynamic properties of the shock absorber are then examined. Stepped sine sweep excitation is currently used in industry to obtain shock absorber parameters along with their frequency and amplitude dependence.
Technical Paper

The Effects of Natural Aging on Fleet and Durability Vehicle Engine Mounts from a Dynamic Characterization Perspective

2001-04-30
2001-01-1449
Elastomers are traditionally designed for use in applications that require specific mechanical properties. Unfortunately, these properties change with respect to many different variables including heat, light, fatigue, oxygen, ozone, and the catalytic effects of trace elements. When elastomeric mounts are designed for NVH use in vehicles, they are designed to isolate specific unwanted frequencies. As the elastomers age however, the desired elastomeric properties may have changed with time. This study looks at the variability seen in new vehicle engine mounts and how the dynamic properties change with respect to miles accumulated on fleet and durability test vehicles.
Technical Paper

Fuel Evaporation Parameter Identification during SI Cold Start

2001-03-05
2001-01-0552
The stochastic properties of continuous time model parameters obtained through discrete least squares estimation are examined. Particular attention is given to the application of estimating the fuel evaporation dynamics of a V-8 SI engine. The continuous time parameter distributions in this case are biased. The bias is shown to be a function of both measurement noise and sampling rate selection. Analysis and experimental results suggest that for each particular model, there is a corresponding optimum sampling rate. A bias compensation formula is proposed that improves the accuracy of least squares estimation without iterative techniques.
Technical Paper

Control Strategies for a Series-Parallel Hybrid Electric Vehicle

2001-03-05
2001-01-1354
Living in the era of rising environmental sensibility and increasing gasoline prices, the development of a new environmentally friendly generation of vehicles becomes a necessity. Hybrid electric vehicles are one means of increasing propulsion system efficiency and decreasing pollutant emissions. In this paper, the series-parallel power-split configuration for Michigan Technological University's FutureTruck is analyzed. Mathematical equations that describe the hybrid power-split transmission are derived. The vehicle's differential equations of motion are developed and the system's need for a controller is shown. The engine's brake power and brake specific fuel consumption, as a function of its speed and throttle position, are experimentally determined. A control strategy is proposed to achieve fuel efficient engine operation. The developed control strategy has been implemented in a vehicle simulation and in the test vehicle.
Technical Paper

Design and Testing of a Single Cylinder, Turbocharged, Four-Stroke Snowmobile with E.F.I. and Catalytic Exhaust Treatment

2002-10-21
2002-01-2761
The successful implementation of a clean, quiet, four-stroke engine into an existing snowmobile chassis has been achieved. The snowmobile is easy to start, easy to drive, and environmentally friendly. The following paper describes the conversion process in detail with actual dynamometer and field test data. The vehicle is partially compliant with the proposed 2010 EPA snowmobile emissions regulations and passes an independently conducted, 74 dBA, full throttle pass-by noise test. The vehicle addresses the environmental issues surrounding snowmobiles and remains economical, with an approximate cost of $6,345.
Technical Paper

Modeling of Human Response From Vehicle Performance Characteristics Using Artificial Neural Networks

2002-05-07
2002-01-1570
This study investigates a methodology in which the general public's subjective interpretation of vehicle handling and performance can be predicted. Several vehicle handling measurements were acquired, and associated metrics calculated, in a controlled setting. Human evaluators were then asked to drive and evaluate each vehicle in a winter driving school setting. Using the acquired data, multiple linear regression and artificial neural network (ANN) techniques were used to create and refine mathematical models of human subjective responses. It is shown that artificial neural networks, which have been trained with the sets of objective and subjective data, are both more accurate and more robust than multiple linear regression models created from the same data.
Technical Paper

Oxidation Catalytic Converter and Emulsified Fuel Effects on Heavy-Duty Diesel Engine Particulate Matter Emissions

2002-03-04
2002-01-1278
The effects of an oxidation catalytic converter (OCC), an emulsified fuel, and their combined effects on particle number and volume concentrations compared to those obtained when using a basefuel were studied. Particle size and particulate emission measurements were conducted at three operating conditions; idle (850 rpm, 35 Nm), Mode 11 (1900 rpm, 277 Nm) and Mode 9 (1900 rpm, 831 Nm) of the EPA 13 mode cycle. The individual effects of the emulsified fuel and the OCC as well as their combined effects on particle number and volume concentrations were studied at two different particle size ranges; the nuclei (less than or equal to 50 nm) and accumulation (greater than 50 nm) modes. An OCC loaded with 10 g/ft3 platinum metal (OCC1) and a 20% emulsified fuel were used for this study and a notable influence on the particle size with respect to number and volume distributions was observed.
Technical Paper

Oxidation Catalytic Converter and Emulsified Fuel Effects on Heavy-Duty Diesel Engine Emissions

2002-03-04
2002-01-1277
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).
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