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In an automotive cooling circuit, the wax melting process determines the net and time history of the energy transfer between the engine and its environment. A numerical process that gives insight into the mixing process outside the wax chamber, the wax melting process inside the wax chamber, and the effect on the poppet valve displacement will be advantageous to both the engine and automotive system design. A fully three dimensional, transient, system level simulation of an inlet controlled thermostat inside an automotive cooling circuit is undertaken in this paper. A proprietary CFD algorithm, Simerics-Sys®/PumpLinx®, is used to solve this complex problem. A two-phase model is developed in PumpLinx® to simulate the wax melting process. The hysteresis effect of the wax melting process is also considered in the simulation.

At various milestones during a vehicle’s development program, different CAE models are created to assess NVH error states of concern. Moreover, these CAE models may be developed in different commercial CAE software packages, each one with its own unique advantages and strengths. Fortunately, due to the wide spread acceptance that the Functional Mock-up Interface (FMI) standard gained in the CAE community over the past few years, many commercial CAE software now support cosimulation in one form or the other. Cosimulation allows performing multi-domain/multi-resolution simulations of the vehicle, thereby combining the advantages of various modeling techniques and software. In this paper, we explore cosimulation of full 3D vehicle model developed in MSC ADAMS with 1D driveline model developed in LMS AMESim. The target application of this work is investigation of vehicle NVH error states associated with both hybridized and non-hybridized powertrains.

High-strength aluminum alloys such as 7075 can be formed using advanced manufacturing methods such as hot stamping. Hot stamping utilizes an elevated temperature blank and the high pressure stamping contact of the forming die to simultaneously quench and form the sheet. However, changes in the thermal history induced by hot stamping may increase this alloy’s stress corrosion cracking (SCC) susceptibility, a common corrosion concern of 7000 series alloys. This work applied the breaking load method for SCC evaluation of hot stamped AA7075-T6 B-pillar panels that had been artificially aged by two different artificial aging practices (one-step and two-step). The breaking load strength of the specimens provided quantitative data that was used to compare the effects of tensile load, duration, alloy, and heat treatment on SCC behavior.

As part of a continuous research and innovation effort, Ford Motor Company has been evaluating hydrogen as an alternative fuel option for vehicles with internal combustion engines since 1997. Ford has recently designed and built an Econoline (E-450) shuttle bus with a 6.8L Triton engine that uses gaseous hydrogen fuel. Safe practices in the production, storage, distribution, and use of hydrogen are essential for the widespread public and commercial acceptance of hydrogen vehicles. Hazards and risks inherent in the application of hydrogen fuel to internal combustion engine vehicles are explained. The development of a Hydrogen Management System (H2MS) to detect hydrogen leaks in the vehicle is discussed, including the evolution of the H2MS design from exploration and quantification of risks, to implementation and validation of a working system on a vehicle. System elements for detection, mitigation, and warning are examined.

Recently, graphene has attracted both academic and industrial interest because it can produce a dramatic improvement in properties at very low filler content. This review will focus on the latest studies and recent progress in the swelling resistance of rubber compounds due to the addition of graphene and its derivatives. This work will present the state-of-the-art in this subject area and will highlight the advantages and current limitations of the use of graphene for potential future researches.

A series of ceria and ceria-zirconia supported Pd model automotive catalysts were prepared and aged under air or redox conditions at 1050°C for 12 h. The supports were manufactured by different methods and represent a range of compositions. The samples were characterized before and after aging by BET, X-ray diffraction, mercury porosimetry, XPS, H2 temperature-programmed reduction, and oxygen storage capacity measurements. Oxygen storage measurements revealed that the behavior of the catalysts varied according to aging conditions and temperature of measurement. Pd/ceria-zirconia catalysts showed higher oxygen storage characteristics after 1050°C aging than Pd/ceria catalysts, and the phase purity of the ceria-zirconia was shown to positively affect the amount of oxygen storage. The initial rates of oxygen release from the model catalysts at 350°C were shown to depend on the preparation conditions of the supports.

This paper presents some of the design rules used to calculate critical geometry of engine components, and the object-oriented component hierarchy system in PET. This paper also presents parametric solid model assembling schemes used to dynamically construct an assembly of whole powertrain systems. Some examples of powertrain concept design, such as the estimation of friction, packaging, and moving component clearances, will be presented. The computational efficiency of this concept design method will be compared to traditional methods also.

Advances in digital and analog electronics have drastically changed car radio circuitry. Improvements in miniaturization of electrical and mechanical components have radically altered their size and styling. Computer modeling of the vehicle's interior environment has optimized car radio acoustics. It seems that the list of modern break-throughs is never ending. It is the intent of this paper to show that many of the technical marvels of today's car radios were first applied years, even decades, ago. From those early concepts, and their current revivals, a projection into the future of automobile radios will be made. As previously mentioned [1]: “If history teaches anything, it teaches the potential for repetition.”

Static seating bucks have long been used as the only means to subjectively appraise the vehicle interior packages in the vehicle development process. The appraisal results have traditionally been communicated back to the requesting engineers either orally or in a written format. Any design changes have to be made separately after the appraisal is completed. Further, static seating bucks lack the flexibility to accommodate design iterations during the evolution of a vehicle program. The challenge has always been on how to build a seating buck quickly enough to support the changing needs of vehicle programs, especially in the early vehicle development phases. There is always a disconnect between what the seating buck represents and what is in the latest design (CAD), since it takes weeks or months to build a seating buck and by the time it is built the design has already been evolved. There is also no direct feedback from seating buck appraisal to the design in CAD.

The high conversion efficiency required by the modern three-way catalyst (TWC) is dependent on oxygen storage material functionality and capacity. To successfully model a TWC, it is critical that the oxygen storage function in the catalyst be adequately represented. The original oxygen storage model (a simple “bucket” model) included in one of Ford's TWC models, SIMTWC, was developed for vehicle programs meeting LEV emission standards. Application of SIMTWC to test data from vehicles targeting more stringent emission standards, such as ULEV and PZEV, revealed limitations in the accuracy of the original bucket model. To address these limitations, an improved kinetic model of oxygen storage is being developed. This new model is more kinetically-detailed than the old model.

The Snook tables (Liberty Mutual Tables) are a collection of data sets compiled from studies based on a psychophysical approach to material-handling tasks. These tables are used to determine safe loads for lifting, lowering, carrying pulling, and pushing. The tables take into account different population percentiles, gender, and frequency of activity. However, while using these tables to analyze a work place, Ergonomists often have to select from discrete data points closest to the actual work place parameters thereby reducing accuracy of results. To compound the problem further, multiple interrelated variables are involved, making it difficult to analyze parameters intuitively. For example, it can be difficult to answer questions such as, does reducing the lifting height lower the recommended lifting weight, if the lifting distance is increased? To resolve such issues, this paper presents a new methodology for implementing the Snook tables using multi variable regression.

Selective catalytic reduction (SCR) is a technology capable of meeting Tier 2 Bin 5 emissions levels of oxides of nitrogen (NOX) for diesel engines. Base metal zeolite catalysts show the best combination of thermal durability and NOX conversion activity. It is shown in this work that some base metal zeolite catalysts can store high levels of hydrocarbons (HCs). Also, base metal zeolite catalysts can catalyze oxidation of HCs under certain conditions. Oxidation of stored hydrocarbons can lead to permanent catalyst deactivation due to the exotherm generated in the SCR catalyst (over-temperature condition leading to SCR catalyst damage). This paper discusses a laboratory bench test to characterize hydrocarbon storage and burn-off characteristics of several SCR catalyst formulations, as well as engine dynamometer tests showing hydrocarbon storage and exotherm generation.

Engine and aftertreatment models have been developed in support of gasoline direct injection (GDI) engine development and aftertreatment system design. A brief overview of the engine models that were used to project emissions and fuel economy performance for the GDI engine is presented. Additionally, the construction and validation of a NOx trap aftertreatment model is described in considerable detail. The insights and increased understanding which have been gained regarding the trade-offs between engine out emission targets, aftertreatment performance, and emission constrained fuel economy benefits for direct injection gasoline engines are reviewed and discussed.

The Micro Motion CMF010P flow meter is a Coriolis-type mass flow meter used to measure dynamic and static flow rate. A detailed review of this system and five other mass flow rate measuring devices was previously completed at Ford Motor Company’s Powertrain and Fuel Subsystems Laboratory [1, 2]. The comparison analyzed the dynamic mass flow rate results of a high-pressure gasoline fuel injector. The Micro Motion flow meter proved to be easy to use while providing sufficient accuracy and repeatability at a reasonable price. The meter’s inherent technology measures the change in flow tube oscillation frequency and twist to obtain highly accurate density and flow rate measurements. Unfortunately, the operating principle can be subject to resonance. Therefore, the resonant frequencies need to be identified and avoided when taking measurements.

A review was conducted of the various fuel injector flow rate measurement methods that are commercially available. The scope of the review was primarily focused on the gasoline applications of Port Fuel Injection (PFI) and Direct Injection Spark Ignition (DISI), but Diesel applications were reviewed as well. These flow meters were compared at the Powertrain & Fuel Subsystems Laboratory (PFSL) of Ford Motor Company. The purpose of this paper is to review the capabilities of each flow meter that is commercially available for use in injector characterization benches and engine test beds.

Wavelets are a powerful mathematical tool used to multi-resolution time-frequency decomposition of signals, in order to analyze them in different scales and obtain different aspects of the information. Despite being a relatively new tool, wavelets have being applied in several areas of human knowledge, especially in signal processing, with emphasis in encoding and compression of image, video and audio. Based on a previous successful applications (FRAZIER, 1999) together a commitment to quality results, this paper evaluates the use of the Discrete Wavelet Transform (DWT) as an compression algorithm to reduce the amount of data collected in road load signals (load history) which are used by the durability engineering teams in the automotive industry.

Statistical Energy Analysis (SEA) is an established high-frequency analysis technique for generating acoustic and vibration response predictions in the automotive, aerospace, machinery, and ship industries. SEA offers unique NVH prediction and target-setting capabilities as a design tool at early stages of vehicle design where geometry is still undefined and evolving and no prototype hardware is available yet for testing. The exact frequencies at which SEA can be used effectively vary according to the size and the amount of damping in the vehicle subsystems; however, for automotive design the ability to predict acoustic and vibration responses due to both airborne and structure-borne sources has been established to frequencies of 500 Hz and above. This paper presents the background, historical use, and current industrial applications of structure-borne SEA. The history and motivation for the development of structure-borne SEA are discussed.

Technical Standards are essential for the expanded use of any engineering material. The Society of Automotive Engineers (SAE) Iron and Steel Castings Committee has been reworking existing, (and issuing new), standards for automotive iron and steel castings. This paper will review the status of the SAE standards for Ductile Iron, Austempered Ductile Iron (ADI), Compacted Graphite Iron (CGI) and high Silicon-Molybdenum (Si-Mo) Ductile Iron, Gray Iron and Steel Castings. The SAE Standards, (and draft standards), will be critically compared to those for ASTM and ISO. Salient differences in the standards will be discussed and implications to design engineers will be addressed. Comparisons to other, competitive materials (and their standards) will be made.

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.

Shielding a vehicle underbody is becoming a daunting task with increased exhaust temperatures due to emissions regulations and ever-increasing packaging constraints, which place components ever closer to exhaust systems. This experimental study was initiated to evaluate the two dimensional thermal effects of heat shield flange height and shield width in vehicle underbody idle conditions. The ultimate goal of this study is to develop a function to optimize the shape of heat shielding to achieve a specified floorpan temperature during vehicle idle conditions.