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The automotive industry continues to develop new powertrain technologies aimed at reducing overall vehicle level fuel consumption. This paper discusses the development of a new highly efficient parallel hybrid transmission for use in transversely installed powertrains for FWD applications. FEV is developing a new 7-speed hybrid transmission for transverse installation. The transmission with a design torque of 320 Nm is based on AMT (automated manual transmission) technology and uses a single electric motor. The innovative gearset layout combines the advantages of modern AMTs such as best efficiency, low costs and few components (reduced part count) with full hybrid capabilities and electric torque support during all gear shifts. Furthermore, the gear set layout allows for very short shift-times due to the favorable distribution of inertias. Other features include an A/C compressor being electrically driven by the electric motor of the transmission during engine start/stop phases.

In the thermal expansion valve (TXV) refrigerant system, transient high-pitched whistle around 6.18 kHz is often perceived following air-conditioning (A/C) compressor engagements when driving at higher vehicle speed or during vehicle acceleration, especially when system equipped with the high-efficiency compressor or variable displacement compressor. The objectives of this paper are to conduct the noise source identification, investigate the key factors affecting the whistle excitation, and understand the mechanism of the whistle generation. The mechanism is hypothesized that the whistle is generated from the flow/acoustic excitation of the turbulent flow past the shallow cavity, reinforced by the acoustic/structural coupling between the tube structural and the transverse acoustic modes, and then transmitted to evaporator. To verify the mechanism, the transverse acoustic mode frequency is calculated and it is coincided to the one from measurement.

A simple set of equations has been developed to characterize automotive fuel behavior in fuel tanks, fuel vapor systems and fuel rails, particularly under hot weather conditions. The system of equations links the vapor pressure P, the temperature T, and the mass fraction evaporated Z. Parameters are determined empirically from laboratory vapor pressure and distillation tests. With appropriate values for heat capacity, heat of vaporization, and vapor composition, the equations can be used to estimate upper flammability limits, fuel weathering under hot fuel handling conditions, pressure rise in tanks, and evaporative vapor generation. The equations were developed as part of a larger fuel vapor system model.

Experimental forms of two different types of engine oil viscosity sensors have been tested that use uniformly poled disks of piezoelectric PZT ceramic. In both cases, the disks were used to form electromechanical resonators functioning as the frequency-controlling element in a transistor oscillator circuit. The simpler type of sensor used only one disk, vibrating in a radial-longitudinal mode of vibration. In this mode, a disk 2.54 cm in diameter and 0.127 cm thick had a resonant frequency of approximately 90 kHz. The second type of sensor used two such disks bonded together by a conducting epoxy, with poling directions oriented in opposite directions. This composite resonator vibrated in a radially-symmetrical, flexural mode of vibration, with the lowest resonant frequency at approximately 20 kHz. The presence of tangential components of motion on the major faces of both resonators made them sensitive to the viscosity of fluids in which they were immersed.

A review of flame kernel growth in SI engines and the regimes of premixed turbulent combustion showed that a misfire model based on regimes of premixed turbulent combustion was warranted[1]. The present study will further validate the misfire model and show that it has captured the dominating physics and avoided extremely complex, yet inefficient, models. Results showed that regimes of turbulent combustion could, indeed, be used for a concept-simple model to predict misfire limits in SI engines. Just as importantly, the entire regimes of premixed turbulent combustion in SI engines were also mapped out with the model.

Ignoring the impact of water condensation leads to incorrect temperature simulation during cold start, and this can lead to questions being raised about the overall accuracy of aftertreatment simulation tools for both temperature and emission predictions. This report provides a mathematical model to simulate the condensation and evaporation of water in exhaust after-treatment devices. The simulation results are compared with experimental data. Simulation results show that the temperature profiles obtained using the condensation model are more accurate than the profiles obtained without using the condensation model. The model will be very useful in addressing questions that concern the accuracy of the simulation tool during cold-start and heating up of catalysts, which accounts for the conditions where tailpipe emission issues are most significant.

Increasing electronics content, growing computing power, and proliferation of opportunities for information connectivity (through improved sensors, GPS, road and traffic information systems, wireless internet access, vehicle-to-vehicle communication, etc.) are technology trends which can significantly transform and impact future automotive vehicle's control and diagnostic strategies. One aspect of the increasing vehicle connectivity is access to ambient and road condition information, such as ambient temperature, ambient pressure, humidity, % cloudiness, visibility, cloud ceiling, precipitation, rain droplet size, wind speed, and wind direction based on wireless internet access. The paper discusses the potential opportunities made available through wireless communication between the vehicle and the internet.

A series of tests have been performed on a production vehicle to determine the characteristics of the external turbulent flow field in wind tunnel and road conditions. Empirical formulas are developed to use the measured data as source levels for a Statistical Energy Analysis (SEA) model of the vehicle structural and acoustical responses. Exterior turbulent flow and acoustical subsystems are used to receive power from the source excitations. This allows for both the magnitudes and wavelengths of the exterior excitations to be taken into account - a necessary condition for consistently accurate results. Comparisons of measured and calculated interior sound levels show good correlation.

While a Ni-MH battery has good performance properties, such as a high power density and no memory effect, it needs a powerful thermal management system to maintain within the required narrow thermal operating range for the 42V HEV applications. Inappropriate battery temperatures result in degradation of the battery performance and life. For the battery cooling system, air is blown into the battery pack. The exhaust is then vented outside due to potential safety issues with battery emissions. This cooling strategy can significantly impact fuel economy and cabin climate control. This is particularly true when the battery is experiencing frequent charge and discharge of high-depths in extreme hot or cold weather conditions. To optimize performance and life of HEV traction batteries, the battery cooling design must keep the battery operation temperature below a maximum value and uniform across the battery cells.

The increasing competitiveness in the automobile market has resulted in the incorporation by the manufacturers of certain features in newer cars that are deemed highly desirable by the customer. Among such features that require improvement is the thermal comfort of passengers' within the cabin. Thermal comfort is in increasing demand from motorists bound to cover more mileage driving cars than ever before. As a result, car makers are striving for improved climate conditions inside the car to meet passenger demand for more comfortable trips. The need to improve the climatic comfort within the vehicle is critical not only to passengers' comfort but also to their safety. However, to make progress in this area, a good understanding of the airflow behaviour within the vehicle interior is required. This paper, reports on a novel idea of control the air movement within the cabin by forcibly removing the air from strategically positioned vents.

A running loss test procedure has been developed which integrates a point-source collection method to measure fuel evaporative running loss from vehicles during their operation on the chassis dynamometer. The point-source method is part of a complete running loss test procedure which employs the combination of site-specific collection devices on the vehicle, and a sampling pump with sampling lines. Fugitive fuel vapor is drawn into these collectors which have been matched to characteristics of the vehicle and the test cell. The composite vapor sample is routed to a collection bag through an adaptation of the ordinary constant volume dilution system typically used for vehicle exhaust gas sampling. Analysis of the contents of such bags provides an accurate measure of the mass and species of running loss collected during each of three LA-4* driving cycles. Other running loss sampling methods were considered by the Auto-Oil Air Quality Improvement Research Program (AQIRP or Program).

The last ten years have experienced a massive integration of consumer electronics devices in vehicles such as mobile phones, audio and video players, USB devices, and internet access capability. Consumers are now demanding the integration of portable and home devices to vehicle systems transforming it to an extension of the home and office thus providing entertainment and connectivity to both short and long trips The integration of devices that were not designed or specified to operate in the vehicle environment has imposed challenges to the engineers designing vehicle electronics systems in particular to the EMC engineers. The need to design the subsystems that are completely integrated with the consumer electronics devices and also compliant with the car makers current specifications has proven to be a major issue due to the fact that one of the components, the consumer electronic devices, cannot be controlled.

Properties of thermoplastic bumpers made of polycarbonate (PC) and polybutylene terephthalate (PBT) blend were evaluated after several years of service in the field. In this study we measured the Izod impact strength, PC molecular weight, and melt flow rate of bumpers collected from various geographical areas in the U.S. Generally, the system had good impact resistance after more than five years of service in the field, retaining most of the original impact strength. There were small changes in PC average molecular-weights and melt flow rates. The results showed that changes depended on both exposure time and the weather conditions of the environment.

Here we present a latent heat storage device which is used to provide “quick/supplemental” heat to the vehicle's conventional heating system. First, we present data from actual in-vehicle cold weather tests. Data are presented for heater and defroster performance tests, emissions tests and cold start tests after extended soaks. Secondly, heater performance predictions are made using a computer simulation program. Finally, the actual heater performance results are compared with the computer simulation.

Flow fields generated during the intake stroke of a 4-stroke I.C. engine are studied experimentally using water analog simulation. The fluid is seeded by small flow tracer particles and imaged by two digital cameras at BDC. Using a 3-D Particle Tracking Velocimetry technique recently developed, the 3-D motion of these flow tracers is determined in a completely automated way using sophisticated image processing and PTV algorithms. The resulting 3-D velocity fields are ensemble averaged over a large number of successive cycles to determine the mean characteristics of the flow field as well as to estimate the turbulent fluctuations. This novel technique was applied to three different cylinder head configurations. Each configuration was run for conditions simulating idle operation two different ways: first with both inlet ports open and second with only the primary port open.

Although concerns have been raised that the performance of activated carbon canisters will decrease when exposed to air at higher humidities, results of a recently conducted test program do not substantiate these concerns. The results show that the purge efficiency and the working capacity of canisters that are purged with air at 75 grains per pound of dry air (GPPDA) humidity are equal or greater than those obtained with 50 GPPDA humidity purging. The results have been submitted to the California Air Resources Board (ARB) for use in aligning their evaporative emission testing regulations with the regulations promulgated by the U. S. Environmental Protection Agency (EPA).

This paper quantifies typical United States in-vehicle cowl area particulate filter parameters such as temperature, humidity and environmental conditions. Secondly, United States and Germany particulate filter fleet results will be included to help quantify the effect of loading on electret nonwoven particulate filter fractional efficiency and demonstrate the amount and types of particulate matter captured. Finally the paper will address the low submicron fractional filter efficiency of a simulated production “wet and dry” plate-fin automotive evaporator core.

A new methodology for rapidly characterizing the in-cylinder flow field at spark ignition for internal combustion engines is described in this paper. The process involves the use of 3-D particle tracking velocimetry to measure the flow field at intake valve closing (IVC) in a water analog engine simulation, and the use of CFD to compute the evolution of the measured flow field during the compression stroke, by using the experimental 3-D PTV results at IVC as the initial condition for the calculations. The technique has been applied to investigate the in-cylinder flow field of a typical 4 valve engine operating in two different modes; one or two intake ports active. The results indicate that in either mode the flow field at IVC is dominated by a different large scale structure: tumble in the case where both intake ports are active and swirl in the case where only one port is active. The results also indicate that these structures evolve differently during the compression stroke.

Painting is the most difficult, the most costly, and the most polluting step in manufacturing vehicles. When low weathering performance paints are used, the results are dissatisfied customers, and huge warranty costs. It would obviously be wise to fully characterize the weathering performance of new coatings systems before they are used. Unfortunately this is not always practical. Coating formulations are changing rapidly in the States to comply with solvent emission regulations, the introduction of plastic substrates, and customer tastes. There is rarely enough time to wait ten years for outdoors exposure tests to reveal the "true" weathering performance of coatings before marketing vehicles. As a result, accelerated tests are often used to guide decisions. However, the results of such tests can be misleading because the harsh exposure conditions used can distort the chemistry of degradation.

A stress durability test method that incorporates exposure to a corrosive environment has been used to evaluate the performance of adhesively bonded steel joints. For the systems examined, corrosion exposure is more damaging than exposure to humidity alone. The combination of load and corrosion exposure is substantially more severe than either alone. A method for analysis of the data and comparison of the test results for the evaluation of adhesive bond durability is proposed. The dependence of lifetime on load is defined as , where f is the ratio of applied load to initial, unexposed failure load. The exponent n provides a measure of the degree of acceleration of the interfacial degradation processes by load.