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With increasingly stringent emissions regulations and concurrent requirements for enhanced engine thermal efficiency, a comprehensive characterization of the automotive gasoline fuel spray has become essential. The acquisition of accurate and repeatable spray data is even more critical when a combustion strategy such as gasoline direct injection is to be utilized. Without industry-wide standardization of testing procedures, large variablilities have been experienced in attempts to verify the claimed spray performance values for the Sauter mean diameter, Dv90, tip penetration and cone angle of many types of fuel sprays. A new SAE Recommended Practice document, J2715, has been developed by the SAE Gasoline Fuel Injection Standards Committee (GFISC) and is now available for the measurement and characterization of the fuel sprays from both gasoline direct injection and port fuel injection injectors.

First LED headlamps will be released into the market in 2007. Special permissions allow this introduction although the official regulation is still under discussion in ECE. The LED technology for front lighting has entered into a new phase from theoretical, prototype status to real and practical applications. Additionally in Europe the legislation, which is under preparation, defines LED modules with one or more LED chips in a row which should be replaceable. With this boundary conditions headlamp suppliers needs to balance between an attractive and innovative styling, demanded by car manufacturers and the light performance to gurantee good visibility at night. The paper describes the methods how to design an LED headlamp with high efficiency by keeping in mind the parameters: packaging, weight, styling and light perfromance. Results with specific design proposals are shown.

Light Emitting Diodes (LEDs) are fast becoming the preferred light sources for automotive lighting applications. They emit light at cone angles equal (hemispherical) or less (conical) than 2Π radians. One way for efficiently collecting and collimating light from LED light sources is to use Near Field Lenses (NFLs). NFLs are collimators using refraction and total internal reflection (TIR) to efficiently collect and direct light. They tend to have thick sections and therefore require challenging molding techniques, and they may have the LED source optically coupled directly into them. Beside these functional aspects, NFLs offer unique styling for different lighting functions such as those in rear combination lamps (RCLs), front turn signal lamps, daytime running lamps (DRLs) and headlamps.

During last 10-15 years we could have seen quite big changes in automotive lighting. The most important changes are: a) plastic materials mostly removed metal and glass material from lighting products raised heat issue of plastics materials b) escalation of competition between lighting suppliers (globalization, merging, …) decrease of time and cost for development of the new product as much as possible

A practical and low cost Blind Spot Monitoring system is proposed. By using a single camera, the range and azimuth position of a vehicle in a blind spot are measured. The algorithm is based on the proposed RWA (Range Window Algorithm). The camera is installed on the door mirror and monitoring the side and rear of the host vehicle. The algorithm processes the image and identifies range and azimuth angle of the vehicle in the adjacent lane. This algorithm is applied to real situations. The 388 images including several kinds of vehicles are analyzed. The detection rate is 86% and the range accuracy is 1.6[m]. The maximum detection range is about 30[m].

As global automobile manufacturers prepare for the phase-out of R134a in Europe, they must address the issue of using the new refrigerant for European sales only or launching the product worldwide. Several factors play into this decision, including cost, service, risk, customer satisfaction, capacity, efficiency, etc. This research effort addresses the minimal vehicle-level hardware differences necessary to provide a European solution of R1234yf while continuing to install R134a into vehicles for the rest of the world. It is anticipated that the same compressor, lubricant and condenser; most fluid transport lines; and in most cases the evaporator can be common between the two systems.

Recovery of potable water from wastewater is essential to the success of long-duration human missions to the moon and Mars. Honeywell International and a team from the NASA Johnson Space Center (JSC) are developing a wastewater processing subsystem that is based on centrifugal vacuum distillation. The wastewater processor, which is referred to as the cascade distillation subsystem (CDS), uses an efficient multistage thermodynamic process to produce purified water. A CDS unit employing a five-stage distiller engine was designed, built, and delivered to the NASA JSC Advanced Water Recovery Systems Development Facility for performance testing; an initial round of testing was completed in fiscal year 2008 (FY08). Based, in part, on FY08 testing, the system is now in development to support an Exploration Life Support Project distillation comparison test that is expected to begin in 2009.

This paper presents the results of a human factors flight test evaluation of a display of Enhanced Traffic Situational Awareness on the Airport Surface with Indications and Alerts (SURF IA). The study is an element of the FAA-sponsored Surface Conflict Detection and Alerting with Consideration of Arrival Applications program. The objective of the flight test was to conduct a comparative evaluation of two candidate SURF IA displays: a detailed Airport Surface Situation Awareness (ASSA) display and a runways-only Final Approach Runway Occupancy Awareness (FAROA) display. Six pilots with a current Air Transport Pilot Certificate each completed 18 scenarios. A Beechcraft King Air C-90 and a Cessna Citation Sovereign aircraft were deployed for the flight tests. The scenarios were conducted at Seattle-Tacoma International Airport and at Snohomish County Paine Field Airport, with each aircraft acting as ‘traffic’ for the other aircraft.

This paper presents new concepts for improving management of the electrical load power regeneration of an aircraft. A novel electrical system that allows for load regeneration back to the distribution bus is described. This approach offers the benefits of reduced weight, volume, and cost, as well as improved reliability. Also described is an electrical machine control mechanism that creates motor power to run the prime mover (i.e., the main engine to dissipate the regenerated power). Instead of main engine generation, this approach can be applied to an auxiliary power unit (APU) or power and thermal management system (PTMS). Background information regarding the regeneration concept is presented. The concept definition and the various modes of operation of the improved system are analyzed and described in detail. Results from the dynamic simulation of the system model are included.

This paper describes two electronic throttle controllers of Visteon Corporation with one already in production and the other currently under development. Analysis and tuning of the two controllers are described. The general structure of the controllers consists of a reference shaping subsystem and a proportional-plus-integral-plus-derivative(PID) controller supplemented with additional terms that deal with the nonlinearility of the electronic throttle body. Due to a friction cancellation term in the controller that minimizes the nonlinearity of the system, linear system analysis techniques are applied. The transfer functions of the electronic throttle body at six different operating conditions are derived. Analysis of the closed-loop dynamics is performed based on the plant and the controller transfer-functions. Controller fine-tuning is performed using frequency response techniques, MATLAB simulations and testing on the actual system.

Water condensate retained inside an automotive evaporator has remained as one of the primary sources of unpleasant “odors”, which in turn can drive up the warranty cost for automotive manufacturers. The “wet” evaporator fin can also underperform due to the presence of condensate blocking the air passage. Moreover, condensate retention can be a potential factor of freezing up evaporators. Thus, an evaporator fin must be designed such that it can shed and drain water condensate as well as provide an excellent heat transfer capability. While the importance of water retention is well known, there seems lacking of a comprehensive way to evaluate the water retention characteristics of a particular product. In this work, attempts were made to answer four questions: (1) What is the mechanism that controls water condensate retention characteristics in an automotive evaporator? (2) Can different water retention evaluation methods reveal the same characteristics?

This paper presents an unambiguous and intuitive method for identification of steering column resonant (SCR) mode of vibration. One simple but overlooked technique to determine the SCR mode in-vehicle is to provide local stiffnesses of the body locations where the Instrument Panel (IP) attaches, to the IP suppliers to be used in their design and development. This paper describes how this technique is useful in predicting the first few important in-vehicle steering column modes for different classes of vehicles, with examples presented in each class. The results obtained from such analyses are compared against those from direct in-buck simulations. This technique is not limited to its application in developing IP systems, but can easily be extended to include other systems such as seats, fuel tanks, etc. Also it is shown that a design optimization analysis may be performed using these attachment stiffnesses as design variables resulting in a system level solution.

Automotive gear oil development has expanded beyond the historical requirements of emphasizing wear protection to encompass modern needs for fuel economy and limited slip frictional properties. This paper describes the development process of a new generation, fuel efficient gear lubricant for use in light duty vehicles. A systematic formulation approach was used, encompassing fluid viscometrics and additive optimization. Performance testing in both laboratory and vehicle tests is described. Though standard GL-5 tests were used to confirm oxidation, wear and corrosion performance, emphasis is given to those methods used for optimizing fuel economy.

Stabilizer bars in a suspension system are supported with bushings by a frame structure. To prevent the axial movement of the stabilizer bar within the bushing, several new stabilizer bar-bushing systems have been developed. The new systems introduce permanent compressive force between the bar and the bushing thereby preventing the relative movement of the bar within the bushing. This mechanical bond between the bar and the bushing can eliminate features such as grippy flats, collars etc. In addition, by controlling the compression parameters, the properties of the bushing such as bushing rates can be tuned and hence can be used to improve the ride and handling performance of the vehicle. In this paper, nonlinear CAE tools are used to evaluate one such compressively loaded bushing system. Computational difficulties associated with modeling such a system are discussed.

Interior compartment doors are required by Federal Motor Vehicle Safety Standard (FMVSS) 201, to stay closed during physical head impact testing, and when subjected to specific inertia loads. This paper defines interior compartment doors, and shows examples of several different latches designed to keep these doors closed. It also explores the details of the requirements that interior compartment doors and their latches must meet, including differing requirements from automobile manufacturers. It then shows the conventional static method a supplier uses to analyze a latch and door system. And, since static calculations can't always capture the complexities of a dynamic event, this paper also presents a case study of one particular latch and door system showing a way to simulate the forces experienced by a latch. The dynamic simulation is done using Finite Element Analysis and instrumentation of actual hardware in physical tests.

Visteon has developed a CAE procedure to qualify instrument panel (IP) products under the vehicle key life test environments, by employing a set of CAE simulation and durability techniques. The virtual key life test method simulates the same structural configuration and the proving ground road loads as in the physical test. A representative dynamic road load profile model is constructed based on the vehicle proving ground field data. The dynamic stress simulation is realized by employing the finite element transient analysis. The durability evaluation is based on the dynamic stress results and the material fatigue properties of each component. The procedure has helped the IP engineering team to identify and correct potential durability problems at earlier design stage without a prototype. It has shown that the CAE virtual key life test procedure provides a way to speed up IP product development, to minimize prototypes and costs.

The purpose of this study is to develop specifically a correlation between Exhaust Manifold Cracking Laboratory Test results and 150,000 mile customer fleet usage test results. The study shows that the exhaust manifold design meets the reliability requirements of 10 years or 150,000 miles, given 90th percentile customer usage without an evidence of cracking or audible leaks. This correlation between the Lab Test and the customer Fleet results has been expressed as an acceleration factor. An acceleration factor is the ratio of how much quicker the engine dynamometer test ( i.e. Lab Test ) can accumulate the effect of customer usage over time versus the customers themselves. The acceleration factor is provided for useful life time period of 10 years or 150,000 miles. The recommended acceleration factor, determined in this study, is 38 to 1, comparing the engine dynamometer test ( i.e. Lab Test ) results to 150,000 mile modular truck customer fleet field results.

Based on our error budget analysis, the urea SCR aftertreatment system is uncontrollable under EPA 2007-emission level without an effective closed-loop control strategy. The objective of the closed-loop control is to improve transient response as well as reduce the steady state control error. But the inherent large dead time in the urea SCR aftertreatment system makes the closed-loop control a challenge. In this paper, an innovative closed-loop control architecture is introduced, which combines model-based feedforward control with variable gain-scheduling feedback control. Transient response is improved with the inverse-dynamic feedforward control and the variable-gain closed-loop control. The steady-state response is improved with the closed-loop control. Based on this new strategy, a controller is designed and validated under the simulation and test cell environment. Comparison with the baseline open-loop controller is also conducted. Finally, some conclusions are presented.

Previously we reported to SAE 2002 the basic principles in materials selections for the fastening of plastics. In this current paper, we will try to increase the understanding of the automotive community regarding the usefulness and applicability of aluminum made self-tapping screws in the fastening of various thermoplastic components. Utilization of the light alloys for the manufacturing of fasteners for plastic applications allowed us to manage efficiently the stiffness considerations, short- and long-term performance of the assembled plastic components. The results presented in this study will help designers, technologists, thermoplastic and fastener developers and fastener manufacturers, to optimize mechanical performance of assembled automotive components, where self-tapping screws will be used.

The quality of outside air during ground operations was analyzed by comparing airport and engine exhaust data to exposure limits and odor thresholds. The results indicated that the outside air may contain compounds in high enough concentrations to be odorous. If the odor is to be treated, the important design criteria that must be considered include the phase of compounds, compound type, location of treatment device on the aircraft, pressure drop, operating temperature, and maintenance interval. Finally, a control strategy is outlined that monitors the air quality as well as the efficiency of an air treatment system.