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Monitoring NO2 Production of a Diesel Oxidation Catalyst

A combination of laboratory reactor measurements and vehicle FTP testing has been combined to demonstrate a method for diagnosing the formation of NO2 from a diesel oxidation catalyst (DOC). Using small cores from a production DOC and simulated diesel exhaust, the laboratory reactor experiments are used to support a model for DOC chemical reaction kinetics. The model we propose shows that the ability to produce NO2 is chemically linked to the ability of the catalyst to oxidize hydrocarbon (HC). For thermally damaged DOCs, loss of the HC oxidation function is simultaneous with loss of the NO2 production function. Since HC oxidation is the source of heat generated in the DOC under regeneration conditions, we conclude that a diagnostic of the DOC exotherm is able to detect the failure of the DOC to produce NO2. Vehicle emissions data from a 6.6 L Duramax HD pick-up with DOC of various levels of thermal degradation is provided to support the diagnostic concept.

High Load HCCI Operation Using Different Valving Strategies in a Naturally-Aspirated Gasoline HCCI Engine

This session focuses on kinetically controlled combustion. Experimental and simulation studies pertaining to various means of controlling combustion are welcome. Examples are research studies dealing with temperature and composition distribution inside the cylinder and their impact on heat release process. Studies clarifying the role of fuel physical and chemical properties in autoignition are also welcome. Presenter Hanho Yun, General Motors Company

Technical Keynote: Leading in Crazy Times

Leading during normal times is plenty challenging. Leading in crazy times requires extra understanding and skill. This presentation explores how you and your team can be your best, regardless of what craziness may be going on around your organization, your team members, and you. Presenter Theresa Rich, General Motors Company

OBD Challenges for Plug In Hybrid Electric Vehicles

Plug-In Hybrid and Extended Range Electric Vehicle's have quickly become the focus of many OEM's and suppliers. Existing regulations and test procedures did not anticipate this rapid adoption of this new technology, resulting in many product development challenges. The lack of clear requirements is further complicated by CARBs consideration of CO2 inclusion in their next light duty OBD regulation. This presentation provides an overview of the regulatory requirements for OBD systems on hybrid vehicles that intend to certify in California. Near term challenges for EREV?s and PHEV?s are discussed, including concerns with the existing denominator and warm-up cycle calculations. Some proposals are made to address these concerns. Presenter Andrew Zettel, General Motors Company

Worldwide OBD

OBD system requirements were first developed by the California Air Resources Board, the U.S. Environmental Protection Agency, and the European Commission. New OBD requirements should be as consistent as possible with existing requirements to maximize reliability and to minimize system complexity, proliferation of configurations, and consumer cost. New OBD requirements from around the world are briefly reviewed and most are consistent with the original U.S. and European requirements. Worldwide OBD requirements are being further harmonized under the United Nations, Economic Commission for Europe, World Forum for Harmonization of Vehicle Regulations (WP29). Presenter David H. Ferris, General Motors Company
Technical Paper

Some Factors in the Subjective Evaluation of Laboratory Simulated Ride

Effects of DOF and subjective method on evaluations of ride quality on the Ford Vehicle Vibration Simulator were studied. Seat track vibrations from 6 vehicles were reproduced on the 6 DOF seat shaker in a DOE with pitch and roll as factors. These appeared in two evaluations of ride/shake; semantic scaling by 30 subjects of 6 vehicles, and paired comparisons by 16 of the subjects on 3 of the vehicles. Both methods found significant vehicle, pitch and roll effects. Order dependence was shown for semantic scaling. The less susceptible paired comparison method gave a different ordering, and is thus preferred.
Technical Paper

Development and Validation of a Pedestrian Lower Limb Non-Linear 3- D Finite Element Model

Lower limb injury is becoming an increasingly important concern in vehicle safety for both occupants and pedestrians. To enable vehicle manufacturers to better understand the biomechanical effects of design changes, it is deemed beneficial to employ a biomechanically fidelic finite element model of the human lower limb. The model developed in this study includes long bones (tibia, fibula, femur) and flat bone (patella) as deformable bodies. The pelvis and foot bones are modeled as rigid bodies connected to the femur and tibia/fibula via rotational spring-dashpots. The knee is defined by scanned bone surface geometry and is surrounded by the menisci, major ligaments, and patellar tendon. Finite elements used to model include 6- and 8-node solids for cartilage, menisci, surrounding muscles, and cancellous bone; 3- and 4-node shells for skin and cortical bone; and nonlinear spring-dashpots for ligaments.
Technical Paper

Evaluation of the Effect of Fuel Composition and Gasoline Additives on Combustion Chamber Deposits

Since 1992 some vehicles have experienced engine knock or rapping noise during cold starts that is caused by combustion chamber deposit interference (CCDI) To better understand the CCDI phenomena, engine dynamometer studies were conducted. Results show that base gasoline composition and detergent additive compositions have significant effects on combustion chamber deposit (CCD) build-up In addition to engine testing, thermogravimetric analysis (TGA) was used to determine a correlation between unwashed gum and CCD levels
Technical Paper

Direct Hydrogen-Fueled Proton-Exchange-Membrane (PEM) Fuel Cell for Transportation, Part 2

A fuel cell (FC) powerplant is an electrochemical engine that converts fuel and an oxidant electrochemically into electric energy, water and other chemical byproducts. When hydrogen is used as the fuel, the only products of the electrochemical reactions are water and electric power. Other conventional and advanced powerplants for transportation, such as the internal combustion (IC) engine, the Diesel engine and others, are thermal combustion engines. The theoretical or thermodynamic efficiency of a fuel cell or electrochemical engine is much higher than the thermodynamic efficiency of a heat engine. The practical efficiency of a fuel cell is highest at partial load, whereas the practical efficiency of a heat engine is highest at maximum power. A survey is presented of the different fuel cell types and their characteristics. The proton-exchange-membrane (PEM) fuel cell is shown to be the best available fuel cell for transportation applications.
Technical Paper

Modeling the Effects of Intake Flow Structures on Fuel/Air Mixing in a Direct-injected Spark-Ignition Engine

Multidimensional computations were carried out to simulate the in-cylinder fuel/air mixing process of a direct-injection spark-ignition engine using a modified version of the KIVA-3 code. A hollow cone spray was modeled using a Lagrangian stochastic approach with an empirical initial atomization treatment which is based on experimental data. Improved Spalding-type evaporation and drag models were used to calculate drop vaporization and drop dynamic drag. Spray/wall impingement hydrodynamics was accounted for by using a phenomenological model. Intake flows were computed using a simple approach in which a prescribed velocity profile is specified at the two intake valve openings. This allowed three intake flow patterns, namely, swirl, tumble and non-tumble, to be considered. It was shown that fuel vaporization was completed at the end of compression stroke with early injection timing under the chosen engine operating conditions.
Technical Paper

Driver Eye Height and Sight Distance on Vertical Curves

Analyses were performed to determine the sensitivity of stopping sight distance on vertical curves to driver eye height and other parameters entering into the stopping sight-distance equations. Sight distance was found to be relatively insensitive to eye height. On a given hill crest, sight distance for a driver whose eye height is 6-inches lower than the design eye height (3.75 ft) is only 5% less than the design sight distance. On the other hand, stopping distance is very sensitive to travel speed, pavement friction and reaction time. For example, a 1.8 mph decrease in speed reduces stopping distance by the same amount that a 6-inch decrease in eye height reduces sight distance. Also, sight distance is about 2.5 times more sensitive to obstacle height than eye height. It is argued that reductions in travel speed since the introduction of the 55-mph speed limit compensate for any recent or projected decreases in driver eye height.
Technical Paper

Ford “S” Frame

Since statistics indicate that front impact is the major accident type, Ford has been studying energy-absorbing structures for some time. Early designs such as the “ball and tube” and “rail splitter” were discarded in favor of the “S” frame. Details of the design approach and testing are given in this paper. Design objectives were increased effective collapse distance, compatibility with production practices, and maintenance of satisfactory noise, vibration, and harshness levels. Safety objectives are improved passenger compartment integrity and reduction of seat belt loads. Barrier crash tests at 30 mph (equivalent to collision into standing vehicle at 50 mph) were used to evaluate the design of the “S” frame. Results of testing indicate that occupant restraint with seat belts, combined with front end structural improvements, offer the most promise for injury reduction during service front impact accidents.
Technical Paper

A Study of Hybrid III 5th Percentile Female ATD Chest Accelerometers to Assess Sternum Compression Rate in Chest on Module Driver Out-of-Position Evaluations

Driver out-of-position (OOP) tests were developed to evaluate the risk of inflation induced injury when the occupant is close to the airbag module during deployment. The Hybrid III 5th percentile female Anthropomorphic Test Device (ATD) measures both sternum displacement and chest acceleration through a potentiometer and accelerometers, which can be used to calculate sternum compression rate. This paper documents a study evaluating the chest accelerometers to assess punch-out loading of the chest during this test configuration. The study included ATD mechanical loading and instrumentation review. Finite element analysis was conducted using a Hybrid III - 5th percentile female ATD correlated to testing. The correlated restraint model was utilized with a Hybrid III - 50th percentile male ATD. A 50th percentile male Global Human Body Model (HBM) was then applied for enhanced anatomical review.
Technical Paper

Experimental Investigation of Fuel Film Characteristics of Ethanol Impinging Spray at Ultra-Low Temperature

Increasing the injection pressure in DISI engine is an efficient way to obtain finer droplets but it will also potentially cause spray impingement on the cylinder wall and piston. Consequently, the fuel film sticking on the wall can dramatically increase the soot emission of the engine especially in a cold start condition. On the other hand, ethanol is widely used as an alternative fuel in DI engine due to its sustainable nature and high octane number. In this study, the fuel film characteristics of single-plume ethanol impinging spray was investigated. The experiments were performed under ultra-low fuel/plate temperature to simulate the cold start condition in cold areas. A low temperature thermostatic bath combined with specially designed heat exchangers were used to achieve ultra-low temperature for both the impinging plate and the fuel. Laser induced fluorescence (LIF) technique was employed to measure the thickness of fuel film deposited on the impinging plate.
Technical Paper

The Ford 427 Cubic Inch Single Overhead Cam Engine

Continuing demands for performance improvements in passenger car engines led to the development of the Ford 427 cu in. single overhead cam engine. See Fig. 1. Author discusses manner in which development of this engine was accomplished, using several design parameters, which included new and previously proved features.
Technical Paper

Performance and Economic Objectives for Over-the-Road Powerplants of the Future

The purpose of this paper is to project the performance and economic objectives of over-the-road powerplants in the decade of the 1970’s. The influencing factors for this projection are trends in: intercity ton miles of freight, size and weight legislation, the interstate highway system maximum legal speed laws, and operating costs of interstate carriers. These factors set the stage and establish the horizon for over-the-road vehicles of tomorrow.
Technical Paper

Recent Developments in Penetration Resistance of Windshield Glass

A twofold improvement in penetration resistance of laminated safety glass for use in vehicle windshields has been achieved. A new test procedure has been established which will provide better correlation of test conditions to accident conditions than present tests do. Present windshield material and the new safety glazings are compared.
Technical Paper

Combustion Chamber Effects on Burn Rates in a High Swirl Spark Ignition Engine

Experimental measurements of burn rates have been carried out in a single cylinder homogeneous charge engine. Three different combustion chambers were investigated (75 % and 60 % squish bowl-in-piston chambers and a disk chamber) using a cylinder head with a swirl producing intake port and near central spark location. Data were obtained with each combustion chamber as a function of spark timing, EGR, and load at 1500 RPM. The combustion rate is strongly influenced by chamber shape. The 10-90 % burn durations of the 75 % and 60 % squish chambers are respectively about 40 % and 60 % that of the disk chamber. Chamber configuration had less effect on 0-10 % burn duration. The disk had about 25 % longer 0-10 % burn time than the bowl-in-piston chambers. Modifications to the GESIM model enabled good overall agreement between predictions and experimental data, a rather severe test of the model because the coupling of fluid mechanics, combustion and chamber geometry must be properly modeled.
Technical Paper

Select Strength Steel Bumper System

The SS Bumper is a new concept in automobile systems that achieves a very significant weight reduction in steel bumper construction and is capable of meeting the 5 mph FMVSS U.S. Government impact standard. It offers a low cost method of achieving a double digit weight reduction with no cost premium for aluminum or plastic materials. This paper concentrates on describing the configuration of the SS Bumper and a simple, easy to apply procedure for car application which includes discrete equations for bending strengths, torsional strength and the new dent strength relationships which have been recently developed. One version of the SS Bumper applied to the 1983 Thunderbird is also described.