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Electrification of Vehicles at Nissan Motor Company to achieve Zero Tailpipe Emissions

2012-03-29
Nissan Motor Company has recently released the �Nissan Green Program 2016� which is a six-year action plan embodying the company�s environmental philosophy: Symbiosis of People, Vehicles and Nature. One of the key activities of this Program is the successful penetration of Zero-Emission Vehicles into the market which includes electric vehicle (EV) cumulative sales of 1.5M units with our Alliance partner Renault, introduction of a fuel cell electric vehicle (FCEV) into the market, taking a global leadership in supplying batteries for electric drive and creating zero-emission societies. This presentation will highlight some of these key activities. Presenter Kev Adjemian, Nissan Technical Center NA
Video

Development and Demonstration of a Low Emissions Four-Stroke Outboard Marine Engine Utilizing Catalyst Technology

2012-06-18
A conceptual project aimed at understanding the fundamental design considerations concerning the implementation of catalyst systems on outboard marine engines was carried out by Mercury Marine, with the support of the California Air Resources Board. In order to keep a reasonable project scope, only electronic fuel injected four-stroke outboards were considered. While they represent a significant portion of the total number of outboard engines sold in the United States, carbureted four-strokes and direct injected two-strokes pose their own sets of design constraints and were considered to be outside the scope of this study. Recently, three-way catalyst based exhaust emissions aftertreatment systems have been introduced into series production on sterndrive and inboard marine spark ignition engines in North America. The integration of catalyst systems on outboards is much more challenging than on these other marine propulsion alternatives.
Journal Article

ERRATUM: Study of Reproducibility of Pedal Tracking and Detection Response Task to Assess Driver Distraction

2015-04-14
2015-01-1388.01
1. On page 111, the authors have described a method to assess driver distraction. In this method, participants maintained a white square size on a forward display by using a game gas pedal of like in car-following situation. The size of the white square is determined by calculating the distance to a virtual lead vehicle. The formulas to correct are used to explain variation of acceleration of the virtual lead vehicle. The authors inadvertently incorporated old formulas they had used previously. In the experiments discussed in the article, the corrected formulas were used. Therefore, there is no change in the results. The following from the article:
Journal Article

1D Thermo-Fluid Dynamic Modeling of Reacting Flows inside Three-Way Catalytic Converters

2009-04-20
2009-01-1510
In this work a detailed model to simulate the transient behavior of catalytic converters is presented. The model is able to predict the unsteady and reacting flows in the exhaust ducts, by solving the system of conservation equations of mass, momentum, energy and transport of reacting chemical species. The en-gine and the intake system have not been included in the simulation, imposing the measured values of mass flow, gas temperature and chemical composition as a boundary condition at the inlet of the exhaust system. A detailed analysis of the diffusion stage triggering is proposed along with simplifications of the physics, finalized to the reduction of the calculation time. Submodels for water condensation and its following evaporation on the monolith surface have been taken into account as well as oxygen storage promoted by ceria oxides.
Journal Article

Reconstruction of Time-Resolved Vehicle Emissions Measurements by Deconvolution

2009-04-20
2009-01-1513
A thorough understanding of vehicle exhaust aftertreatment system performance requires time-resolved emissions measurements that accurately follow driving transients, and that are correctly time-aligned with exhaust temperature and flow measurements. The transient response of conventional gas analyzers is characterized by both a time delay and an attenuation of high-frequency signal components. The distortion that this imposes on transient emissions measurements causes significant errors in instantaneous calculations of aftertreatment system efficiency, and thus in modal mass analysis. This creates difficulties in mathematical modeling of emissions system performance and in optimization of powertrain control strategies, leading to suboptimal aftertreatment system designs. A mathematical method is presented which improves the response time of emissions measurements. This begins with development of a model of gas transport and mixing within the sampling and measurement system.
Journal Article

Treatment of Vehicle Emissions from the Combustion of E85 and Gasoline with Catalyzed Hydrocarbon Traps

2009-04-20
2009-01-1080
Ethanol has been gaining attention as a partial substitute in North American pump gasoline in amounts up to 85% ethanol and 15% gasoline, or what is commonly known as “E85”. The problems with E85 fuel for cold start emissions relative to gasoline fuel are the lower energy density and vapor pressure for combustion. Each contributes to excess E85 fuel injected during cold start for comparable combustion quality and drivability to gasoline. The excess emissions occur before the first three-way catalyst (TWC) converter is warmed-up and active for engine-out exhaust conversion. The treatment of non-methane organic gas (NMOG) emissions from the combustion of E85 and gasoline was evaluated using several different zeolite based hydrocarbon (HC) traps coated with different precious metal loadings and ratios. These catalyzed HC traps were evaluated in a flow reactor and also on a gasoline Partial Zero Emissions Vehicle (PZEV) with experimental flexible fuel capability.
Journal Article

Metering Characteristics of a Closed Center Load - Sensing Proportional Control Valve

2009-10-06
2009-01-2850
The investigation of the flow through the metering section of hydraulic components plays a fundamental role in the design and optimization processes. In this paper the flow through a closed center directional control valve for load -sensing application is studied by means of a multidimensional CFD approach. In the analysis, an open source fluid-dynamics code is used and both cavitation and turbulence are accounted for in the modeling. A cavitation model based on a barotropic equation of state and homogeneous equilibrium assumption, including gas absorption and dissolution in the liquid medium, is adopted and coupled to a two equation turbulence approach. Both direct and inverse flows through the metering section of the control valve are investigated, and the differences in terms of fluid - dynamics behavior are addressed In particular, the discharge coefficient, the recirculating regions, the flow acceleration angle and the pressure and velocity fields are investigated and compared.
Journal Article

Virtual Multi-Cylinder Engine Transient Test System

2009-09-13
2009-24-0106
Researchers at the Powertrain Control Research Laboratory (PCRL) at the University of Wisconsin-Madison have developed a transient test system for single-cylinder engines that accurately replicates the dynamics of a multi-cylinder engine. The overall system can perform very rapid transients in excess of 10,000 rpm/second, and also replicates the rotational dynamics, intake gas dynamics, and heat transfer dynamics of a multi-cylinder engine. Testing results using this system accurately represent what would be found in the multi-cylinder engine counterpart. Therefore, engine developments can be refined to a much greater degree at lower cost, and these changes directly incorporated in the multi-cylinder engine with minimal modification. More importantly, various standardized emission tests such as the cold-start, FTP or ETC, can be run on this single-cylinder engine.
Journal Article

Evaluation of ANITA Air Monitoring on the International Space Station

2009-07-12
2009-01-2520
ANITA (Analysing Interferometer for Ambient Air) is a flight experiment precursor for a permanent continuous air quality monitoring system on the ISS (International Space Station). For the safety of the crew, ANITA can detect and quantify quasi-online and simultaneously 33 gas compounds in the air with ppm or sub-ppm detection limits. The autonomous measurement system is based on FTIR (Fourier Transform Infra-Red spectroscopy). The system represents a versatile air quality monitor, allowing for the first time the detection and monitoring of trace gas dynamics, with high time resolution, in a spacecraft atmosphere. ANITA operated on the ISS from September 2007 to August 2008. This paper summarises the results of ANITA's air analyses and compares results to other measurements acquired on ISS during the operational period.
Journal Article

Counter-Flow Silica-Titania Reactor for the Simultaneous Treatment of Air and Water Contaminated with VOCs

2009-07-12
2009-01-2524
The photocatalytic oxidation of VOCs was investigated using a novel countercurrent flow reactor designed to enable the treatment of toluene present in the gas and the aqueous phases simultaneously. The reactor was packed with silica-titania composites commingled with plastic pall rings. Using this mixed packing style was advantageous as it resulted in a higher UV penetration throughout the reactor. The average UV intensity in the reactor was determined to be 220 μW/g irradiated TiO2. It was found that under dry conditions, the STCs had a high adsorption capacity for toluene; however, this adsorption was completely hindered by the wetting of the STCs when the two phases were flowing simultaneously. The destruction of toluene in the aqueous phase was determined to follow a linear trend as a function of the contaminant concentration.
Journal Article

Effects of Secondary Air Injection During Cold Start of SI Engines

2010-10-25
2010-01-2124
An experimental study was performed to develop a more fundamental understanding of the effects of secondary air injection (SAI) on exhaust gas emissions and catalyst light-off characteristics during cold start of a modern SI engine. The effects of engine operating parameters and various secondary air injection strategies such as spark retardation, fuel enrichment, secondary air injection location and air flow rate were investigated to understand the mixing, heat loss, and thermal and catalytic oxidation processes associated with SAI. Time-resolved HC, CO and CO₂ concentrations were tracked from the cylinder exit to the catalytic converter outlet and converted to time-resolved mass emissions by applying an instantaneous exhaust mass flow rate model. A phenomenological model of exhaust heat transfer combined with the gas composition analysis was also developed to define the thermal and chemical energy state of the exhaust gas with SAI.
Journal Article

Direct Injection of High Pressure Gas: Scaling Properties of Pulsed Turbulent Jets

2010-10-25
2010-01-2253
Existing gasoline DI injection equipment has been modified to generate single hole pulsed gas jets. Injection experiments have been performed at combinations of 3 different pressure ratios (2 of which supercritical) respectively 3 different hole geometries (i.e. length to diameter ratios). Injection was into a pressure chamber with optical access. Injection pressures and injector hole geometry were selected to be representative of current and near-future DI natural gas engines. Each injector hole design has been characterized by measuring its discharge coefficient for different Re-levels. Transient jets produced by these injectors have been visualized using planar laser sheet Mie scattering (PLMS). For this the injected gas was seeded with small oil droplets. The corresponding flow field was measured using particle image velocimetry (PIV) laser diagnostics.
Journal Article

Proof-of-Principle Investigation into the Use of Custom Rapid Aging Procedures to Evaluate and Demonstrate Catalyst Durability

2010-10-25
2010-01-2269
The application of accelerated catalyst aging procedures on an engine dynamometer test bed for the purpose of demonstrating catalyst durability is examined. A proof-of-principle approach is followed using catalysts from vehicles certified to U.S. Tier 2 Bin 4 and California SULEV 2 levels. Accelerated durability demonstration methods based upon conventional fuel cut cycles were employed to age catalysts to levels predicted by quantification of thermal catalyst bed severity on the Standard Road Cycle (SRC) relative to the fuel cut aging cycle using the Bench Aging Time (BAT) equation. Emissions deterioration on the accelerated aging cycle is compared to the automobile manufacturers' certification values and to whole vehicle emissions performance results from several different in-use vehicle fleets. The influence of technology on whole vehicle emissions levels and deterioration characteristics is also evaluated.
Journal Article

Achieving an 80% GHG Reduction by 2050 in California's Passenger Vehicle Fleet: Implications for the ZEV Regulation

2010-10-19
2010-01-2306
In recognizing the potential for large, damaging impacts from climate change, California enacted Executive Order S-03-05, requiring a reduction in statewide greenhouse gas (GHG) emissions to 80% below 1990 levels by 2050. Given that the transportation light-duty vehicle (LDV) segment accounts for 28% of the state's GHG emissions today, it will be difficult to meet the 2050 goal unless a portfolio of near-zero carbon transportation solutions is pursued. Because it takes decades for a new propulsion system to capture a large fraction of the passenger vehicle market due to vehicle fleet turn-over rates, it is important to accelerate the introduction of these alternatives to ensure markets enter into early commercial volumes (10,000s) between 2015 and 2020. This report summarizes the results and conclusions of a modeling exercise that simulated GHG emissions from the LDV sector to 2050 in California.
Journal Article

Effect of Flash Gas Bypass on the Performance of R134a Mobile Air-Conditioning System with Microchannel Evaporator

2011-04-12
2011-01-0139
This paper demonstrates that the implementation of Flash Gas Bypass method can improve the performance of conventional direct expansion R134a mobile air-conditioning system with a microchannel evaporator. This method uses flash gas tank after expansion valve to separate and bypass flash refrigerant vapor around the evaporator, and feed the evaporator with only liquid refrigerant. Pressure drop is reduced and refrigerant distribution is significantly improved, resulting in higher evaporator effectiveness and evaporation pressure. Both lower pressure drop and lifted evaporation pressure allows the compressor to work with lower pressure ratio, saving required compressor work. An experimental comparison of the direct expansion system shows that Flash Gas Bypass method increases the cooling capacity and COP at the same time by up to 16% and 11%, respectively.
Journal Article

Analysis of In-Cylinder Hydrocarbons in a Multi-Cylinder Gasoline HCCI Engine Using Gas Chromatography

2009-11-02
2009-01-2698
Gasoline Homogeneous Charge Compression Ignition (HCCI) combustion has been studied widely in the past decade. However, in HCCI engines using negative valve overlap (NVO), there is still uncertainty as to whether the effect of pilot injection during NVO on the start of combustion is primarily due to heat release of the pilot fuel during NVO or whether it is due to pilot fuel reformation. This paper presents data taken on a 4-cylinder gasoline direct injection, spark ignition/HCCI engine with a dual cam system, capable of recompressing residual gas. Engine in-cylinder samples are extracted at various points during the engine cycle through a high-speed sampling system and directly analysed with a gas chromatograph and flame ionisation detector. Engine parameter sweeps are performed for different pilot injection timings and quantities at a medium load point.
Journal Article

Method and System for Making a Fuel-tank Inert without an Inert Gas

2009-11-10
2009-01-3134
In Chemistry “Inert” implies ‘not readily reactive with other elements; forming few or no chemical compounds or something that is not chemically active’. “Inerting” is the process that renders a substance inert. A method for making a fuel-tank inert without the use of an inert gas is described. In this method fuel-air ratio of ullage is reduced until it becomes inert. The method does not discharge fuel vapors as an inert gas inerting system. Two systems employing the method are described explaining their pros and cons. Advantages of the method over Nitrogen Enriched Air (NEA) inerting method with an On-board Inert Gas Generating System (OBIGGS) are discussed. Patent application on the method and system is pending.
Journal Article

A Study of HCCI Combustion using Spectroscopic Techniques and Chemical Kinetic Simulations

2009-11-03
2009-32-0070
This study was conducted to investigate the influence of low-temperature reactions on the Homogeneous Charge Compression Ignition (HCCI) combustion process. Specifically, an investigation was made of the effect of the residual gas condition on low-temperature reactions, autoignition and the subsequent state of combustion following ignition. Light emission and absorption spectroscopic measurements were made in the combustion chamber in order to investigate low-temperature reactions in detail. In addition, chemical kinetic simulations were performed to validate the experimental results and to analyze the elemental reaction process. The results made clear the formation behavior of the chemical species produced during low-temperature HCCI reactions.
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