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The effect of pre-catalyst speciation on lean NOx catalysis was investigated using a chemically defined fuel matrix. Nine model fuels and a diesel fuel were injected into the exhaust stream of a medium duty diesel engine prior to a DeNOx catalyst. NOx conversions ranged from 9% at a mid speed and load test point to 43% at a higher load test point. On an absolute basis, model fuels produced up to 34% greater NOx conversions relative to diesel. Speciation revealed that, compared with low temperature test points, cracking and oxidation at peak torque significantly modified the auxiliary HC input to the catalyst. The quantity of ‘cracked’ derivatives of the auxiliary fuel, namely alkene and carbonyl species, correlated well with NOx conversions.

By early 2007, all major manufacturers of light-duty diesel vehicles are marketing models equipped with diesel particulate filters (DPFs). However, there is still a lack of understanding of the particles emitted when the DPF undergoes regeneration. This paper focuses on measuring particle emissions of a representative light-duty diesel vehicle equipped with DPF and employing a fuel-borne catalyst (FBC) to aid regeneration. Particulate Matter (PM) and non-volatile particle number emissions are measured throughout testing according to the Particle Measurement Programme (PMP) proposals. In addition, an Engine Exhaust Particle Sizer (EEPS) connected directly to the CVS is used to give real time size distributions of both volatile and non-volatile particles. The paper focuses on particle emissions during regenerating New European Driving Cycles (NEDCs).

The automotive industry is pursuing significant cost competitive efforts to reduce vehicle weight while maintaining or improving durability and impact performance. One such effort for the body shell structure is the utilization of advanced and ultra high strength steels (AHSS and UHSS) using the existing automotive manufacturing infrastructure. Common AHSS and UHSS steels include Dual Phase (DP), Transformation Induced Plasticity (TRIP), Partial Martensitic (PM) and others. The use of these multiphase high strength steels for impact dependent components has resulted in the need for further material characterization in order to better predict impact performance and guide new material development. This paper addresses the material properties and microstructural influences on impact behavior of advanced and ultra high strength steels through the use of laboratory tests and component level testing.

Simple component models are advantageous when simulating vehicle AC systems so that overall model complexity and computation time can be minimized. These models must be robust enough to avoid instability in the iteration method used for determining the AC system operating or “balance” point. Simplicity and stability are especially important when the AC system model is coupled with a vehicle interior model for studies of transient performance because these are more computationally intensive. This paper presents a semi-empirical modeling method for compressors based on dimensionless parameters. Application to some sample compressor data is illustrated. The model equations are simple to employ and will not introduce significant stability problems when used as part of a system simulation.

The effect of hydroforming on the mechanical properties and dynamic crush behaviors of tapered aluminum 6063-T4 tubes with octagonal cross section are investigated by experiments. First, the thickness profile of the hydroformed tube is measured by non-destructive examination technique using ultrasonic thickness gauge. The effect of hydroforming on the mechanical properties of the tube is investigated by quasi-static tensile tests of specimens prepared from different regions of the tube based on the thickness profile. The effect of hydroforming on the dynamic crush behaviors of the tube is investigated by axial crush tests under dynamic loads. Specimens and tubes are tested in two different heat treatment conditions: hydroformed-T4 (as-received) and T6. The results of the quasi-static tensile tests for the specimens in hydroformed-T4 condition show different amounts of work hardening depending on the regions, which the specimens are prepared from.

The implementations of the Tier 2 and LEVII emission levels require fast catalyst light-off and fast closed loop control through high-speed engine management. The paper describes the development of innovative catalyst designs. During the development thermal and mechanical boundary conditions were collected and component tests conducted on test rigs to identify the emission and durability performance. The products were evaluated on a Super Imposed Test Setup (SIT) where thermal and mechanical loads are applied to the test piece simultanously and results are compared to accelerated vehicle power train endurance runs. The newly developed light-off catalyst with Perforated Foil Technology (PE) showed superior emission light-off characteristic and robustness.

An experiment was performed with a 1.3L catalytic converter design containing a front and rear catalyst each having a volume of 0.65 liters. This investigation varied the front catalyst parameters to study the effects of 1) substrate diameter, 2) substrate cell density, 3) Pd loading and 4) Rh loading on the FTP emissions on three different vehicles. Engine displacement varied from 2.4L to 4.7L. Eight different converters were built defined by a Taguchi L-8 array. Cold flow converter restriction results show the tradeoff in converter restriction between substrate cell density and substrate diameter. Vehicle FTP emissions show how the three vehicles are sensitive to the four parameters investigated. Platinum Group Metals (PGM) prices and Federal Test Procedure (FTP) emissions were used to define the emission value between the substrate properties of diameter and cell density to palladium (Pd) and rhodium (Rh) concentrations.

This paper presents the results of CFD study on sunroof buffeting suppression using a dividing bar. The role of a dividing bar in side window buffeting case was illustrated in a previous study [8]. For the baseline model of the selected vehicle in this study, a very high level of sunroof buffeting, 133dB, has been found. The CFD simulation shows that the buffeting noise can be significantly reduced if a dividing bar is installed at the sunroof. A further optimization study on the dividing bar demonstrates that the peak buffeting level can be reduced to 123dB for the selected vehicle if the dividing bar is installed at its optimal location, 65% of the total length from the front edge of the sunroof. The peak buffeting level can be further reduced to 100dB if the dividing bar takes its optimal width 80mm, 15% of the total length of the sunroof for this vehicle, while staying at its optimal location.

More than 200 tensile-shear resistance spot welded specimens were produced and tested to analyze the effect of spot weld spacing, weld size, sheet thickness, and adhesive on the ultimate strength of joints made from a mild hot dip galvannealed steel and an unexposed quality hot dip galvannealed 590 MPa minimum tensile strength dual phase steel (DP590). The geometric layout parameters were analyzed by a design of experiment (DOE) approach. The analysis showed that weld size is a primary factor affecting the strength of the joints for a given material. It was also determined that structural adhesive created a large relative strengthening for joints made from the mild steel. Interactions of the geometrical factors are also presented.

The relationship between the response (output) and the input factors on a system or process is always needed. This relationship can be used to optimize the response. The Central Composite Design (CCD) is the most commonly used in response surface study. The Uniform Design (UD) can have a small number of experiments to explore relationship between the response and the factors. In this paper, the physics-based simulation model of a “Heater fan motor” will be used to investigate the accuracy of the response (angular velocity) by the prediction models from CCD and UD.

The National Renewable Energy Laboratory (NREL) collaborated with Millennium Cell and DaimlerChrysler to study heat and water management in a sodium borohydride (NaBH4) storage/processor used to supply hydrogen to a fuel cell in an automotive application. Knowledge of heat and water flows in this system is necessary to maximize the storage concentration of NaBH4, which increases vehicle range. This work helps evaluate the NaBH4 system's potential to meet the FreedomCAR program technical target of 6 wt% hydrogen for hydrogen storage technologies. This paper also illustrates the advantages of integrating the NaBH4 hydrogen processor with the fuel cell.

Electronics is driving 90% of the functional innovation in vehicles which is generating a demand for more (single function) control units to realise the new feature content. Adding such extra ECU's cannot be supported without limit due to packaging space on the vehicle and the significant increase in electrical system complexity. Also, the need for functional integration (between ECU's) is necessary to satisfy key market trends for improved vehicle safety and drive-by-wire capability. This need would not be met by lots of single function ECU's which is leading to a demand for new in-vehicle network architectures. At the same time, the OEM's are looking to define the vehicle “brand image” through advanced software applications which need to be integrated with supplier software within multiple ECU's.

Conventional engine HiL simulators use Mean Value (MV) modelling techniques to represent the plant and provide closed loop feedback parameters to the ECU. Once configured, these models require parameterising with the engine specific data. This data can be obtained from two primary sources: Test bed data - running a range of steady state/dynamic speed/load points. Engine required. WAVE* simulation model - Physical sizes of engine required for simulation. No Engine required. The accuracy of the MV model once fully parameterised is in the region of 70 - 80% assuming accurate test data. Another limitation of current techniques is that differences between individual cylinders, for example due to intake system geometrical arrangement, are ignored.

Electronic Control Units (ECUs) are typically programmed using external programming devices - frequently called Diagnostic Testers. We propose a system and software architecture that requires no Diagnostic Tester for ECU (re)programming. ECU (re)programming is instead managed by an on-board software component, the Flashware-Reprogramming-Controller. It can reside in any ECU that has sufficient memory and processing power as well as good connectivity to internal networks and external sources from which to receive the software to be installed. Appropriate choices could be modern telematic devices. A second co-located on-board software component - the Installation-Configuration-Controller - is used to supervise the installation of new software releases and to validate their integrity after installation. The proposed architecture can be used for software download into ECUs in development, end-of-line production and after sales.

To meet the future low emission targets for Diesel engines, engineers are optimising both the fuel injection and after treatment systems fitted to Diesel engines. In order to optimise the fuel injection system there is a need to characterize the fuel spray for a given injection nozzle geometry and injection pressure/duration. Modern Diesel common rail systems produce very dense sprays, making in-cylinder investigation particularly difficult. In this study the measurement of droplet sizes and velocities in dense Diesel sprays has been investigated using Phase Doppler Anemometry (PDA). PDA has been proven to be a valuable technique in providing an understanding of the structure and characteristics of liquid sprays in many studies. It is often applied to finely atomised and dispersed particle flows.

As part of an ongoing investigation, the influence of In Cylinder Pressure (ICP) and fuel injection pressure on the soot formation processes in a diesel fuel spray were studied. The work was performed using a rapid compression machine at ambient conditions representative of a modern High Speed Direct Injection diesel engine, and with fuel injection more representative of full load. Future tests will aim to consider the effects of pilot injections and EGR rates. The qualitative soot concentration was determined using the Laser Induced Incandescence (LII) technique both spatially and temporally at a range of test conditions. Peak soot concentration values were determined, from which a good correlation between soot concentration and injection pressure was observed. The peak soot concentration was found to correlate well with the velocity of the injected fuel jet.

The cambore distortion is one of major concerns of an engine performance. A good design does not ensure a quality product. To meet product performance requirements, engineering community turns efforts to both design and manufacturing at an early stage of product development. This paper will discuss this process by providing an example of design and manufacturing of an overhead cambore. In this study a methodology to evaluate bore distortions is introduced. FEA cambore distortion analysis will use it to provide necessary data so that the product team can make a sound decision.

Vehicle exhaust flow is difficult to measure accurately and with high precision due to the highly transient nature of the cyclic events which are dependent on engine combustion parameters, varying exhaust gas compositions, pulsation effects, temperature and pressure. Bag mini-diluter (BMD) is becoming one of the few technologies chosen for SULEV and PZEV exhaust emission measurement and certification. A central part of the BMD system is an accurate and reliable exhaust flow measurement which is essential for proportional bag fill. A new device has been developed to accurately and reliably calibrate exhaust flow measurement equipments such as the E-Flow. The calibration device uses two different size laminar flow elements (LFE), a 40 CFM (1.13 m3/min) LFE for low end calibration and a 400 CFM (11.32 m3/min) LFE for higher flows. A blower is used to push flow through a main flow path, which then divides into two flow pathways, one for each of the two LFE's.

Automakers in the United States have started using bag mini-diluters (BMD) for developing, testing and certifying vehicles, to meet PZEV and SULEV regulation requirements. The BMD system which is a new technology developed by AIGER, is being used as an alternative to the traditional CFV/CVS system for accurate ultra low-level emission measurement. BMD system has shown to have considerable advantage over CFV/CVS system, especially at ULEV/SULEV emission levels. This paper details modifications and diagnostic checks conducted with the existing BMD system at the DaimlerChrysler Tech Center emissions facility, Auburn Hills, Michigan. This paper also discusses possible scenarios where the BMD system at DaimlerChrysler could give erroneous results due to system setup, optimization issues and equipment limitations.

Researchers at the National Renewable Energy Laboratory conducted outdoor vehicle thermal soak tests in Golden, Colorado, in September 2002. The same environmental conditions and vehicle were then tested indoors in two DaimlerChrysler test cells, one with metal halide lamps and one with infrared lamps. Results show that the vehicle's shaded interior temperatures correlated well with the outdoor data, while temperatures in the direct sun did not. The large lamp array situated over the vehicle caused the roof to be significantly hotter indoors. Yet, inside the vehicle, the instrument panel was cooler due to the geometry of the lamp array and the spectral difference between the lamps and sun. Results indicate that solar lamps effectively heat the cabin interior in indoor vehicle soak tests for climate control evaluation and SCO3 emissions tests. However, such lamps do not effectively assess vehicle skin temperatures and glazing temperatures.