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A dynamic computer model of automotive air conditioning systems was developed. The model uses simulation software for the coding of 1-D heat transfer, thermodynamics, fluid flow, and control valves. The same software is used to model 3-D solid dynamics associated with mechanical mechanisms of the compressor. The dynamics of the entire AC system is thus simulated within the same software environment. The results will show the models potential applications in component and system design, calibration and control.

Virtual design validation of an air induction system (AIS) requires a proper finite element (FE) assembly model for various simulation based design tasks. The effect of the urethane air filter seal within an AIS assembly, however, still poses a technical challenge to the modeling of structural dynamic behaviors of the AIS product. In this paper, a filter seal model and its modeling approach for AIS assemblies are introduced, by utilizing the feature finite elements and empiric test data. A bushing element is used to model the unique nonlinear stiffness and damping properties of the urethane seal, as a function of seal orientation, preloading, temperature and excitation frequency, which are quantified based on the test data and empiric formula. Point mobility is used to character dynamic behaviors of an AIS structure under given loadings, as a transfer function in frequency domain.

In developing a direct injection gasoline engine, the in-cylinder fuel air mixing is key to good performance and emissions. High speed visualization in an optically accessible single cylinder engine for direct injection gasoline engine applications is an effective tool to reveal the fuel spray pattern effect on mixture formation The fuel injectors in this study employ the unique multi-hole turbulence nozzles in a PFI-like (Port Fuel Injection) fuel system architecture specifically developed as a Low Pressure Direct Injection (LPDI) fuel injection system. In this study, three injector sprays with a narrow 40° spray angle, a 60°spray angle with 5°offset angle, and a wide 80° spray angle with 10° offset angle were evaluated. Image processing algorithms were developed to analyze the nature of in-cylinder fuel-air mixing and the extent of fuel spray impingement on the cylinder wall.

Accurate evaluation of vehicles' transient total power requirement helps achieving further improvements in vehicle fuel efficiency. When operated, the air-conditioning (A/C) system is the largest auxiliary load on a vehicle, therefore accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation models, such as "Autonomie," have been used by OEMs to evaluate vehicles' energy performance. However, the load from the A/C system on the engine or on the energy storage system has not always been modeled in sufficient detail. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software MATLAB/Simulink® is frequently used by vehicle controls engineers to develop new and more efficient vehicle energy system controls.

SAE Paper 2002-01-2894 entitled, “The Impact of MMT Gasoline Additive on Exhaust Emissions and Fuel Economy of Low Emission Vehicles (LEV)” presents discussion and conclusions concerning the emissions from vehicles that accumulated mileage on gasoline with and without the fuel additive, methylcyclopentadienyl manganese tricarbonyl (or MMT®). Although the authors of the paper express concern about use of MMT®, the data on which the authors rely are consistent with the results and conclusions from prior evaluations of MMT® which have found that MMT® is compatible with effective emission control system operation (1,2,3). All vehicles tested in the study met the emission standards for all pollutants that apply to the test vehicles in-use and analysis of the data show MMT® had no effect on fuel economy.

The traditional method of engine knock detection is to compare the knock intensity with a predetermined threshold. The calibration of this threshold is complex and difficult. A statistical knock detection method is proposed in this paper to reduce the effort of calibration. This method dynamically calculates the knock threshold to determine the knock event. Theoretically, this method will not only adapt to different fuels but also cope with engine aging and engine-to-engine variation without re-calibration. This method is demonstrated by modeling and evaluation using real-time engine dynamometer test data.

System integration is the path to successful entry of hybrid electric vehicle (HEV) technology into the marketplace. A modular solution capable of meeting varying customer requirements is needed. The controller must possess a flexible hierarchical architecture that insures cross-platform compatibility and provides adaptability for various engine, motor, transmission, and battery configurations. A hybrid powertrain supervisory controller (PSC) has been designed for an advanced parallel-type HEV prototype, which uses a continuously variable transmission (CVT). The controller schedules torque commands for the engine and motor and chooses the transmission ratio to meet driver demanded acceleration. The controller is organized around a state machine, which determines how best to employ powertrain components to satisfy the driver while maximizing fuel economy.

This paper gives an overview of a scalable engine management system architecture for motorcycle and other small engine based vehicle applications. The system can accommodate any engine sizes and up to four cylinders. The architecture incorporates advanced functionalities such as oxygen sensing, closed loop fueling, wall-wetting compensation, purge control, start & idle control and deceleration fuel cut-off. Additionally, a number of vehicle-related controls are integrated in the system. Diagnostic and safety related features have also been incorporated with limp-home capability. The software architecture is compatible with different hardware solutions. The system has been implemented in several OEM vehicles around the globe and meets EURO-3 emission requirements.

The long-term durability of a vehicle's exhaust catalyst is essential for emission control. Catalyst durability can be affected by a variety of factors including engine oil consumption. During normal engine operation, some of the lubricating oil is combusted. The deposition of combustion products from phosphorus containing lubricant additives on the catalyst can adversely affect catalyst durability. In an attempt to minimize the impact of oil consumption on additive performance, engines have been designed to reduce oil consumption and oils are being formulated with lower concentrations of phosphorus compounds. However, these phosphorus compounds protect the engine from excessive wear and cannot be easily removed from lubricant oil due to concerns over engine durability. The use of a phosphorus scavenger is an approach that works together with engine design to minimize catalyst deterioration.

Knock correction is the spark angle retard applied to the optimum ignition timing to eliminate knock. In adaptive knock control, this amount of spark retard at an operating point (i.e. Speed, load) is stored in a speed/load characteristic map. It will be reused when the engine is operated in this range once more. In this paper, a method to learn the knock correction values into a speed/load characteristic map is described. This method proportionally distributes the knock correction into the characteristic map according to the distance between the speed/load of these nodes and the current operating point. The distributed knock correction value is filtered and accumulated in its adjacent nodes. Simulation examples demonstrate that the retrieved values from the map by the proposed method are smoother than those produced by the method of [2][3]. The mathematical basis for this method is developed. The one and two independent variable cases are illustrated.

In July 2002, the Alliance of Automobile Manufacturers, the Association of International Automobile Manufacturers and the Canadian Vehicle Manufacturers Association released the results of a 6-year, two-part vehicle fleet test program to determine the effects of methyl-cyclopentadienyl manganese tricarbonyl (MMT®*) on vehicles equipped with state of the art emission control systems. Analysis of the data reports from this study shows that all of the vehicles met applicable emission standards, even though the fleet accumulated mileage under very severe conditions that accelerate degradation of vehicle emission control systems in excess of that expected from actual vehicle mileage. The study also demonstrated that gasoline-containing MMT had no adverse impact on vehicular emission control equipment.

MMT (methylcyclopentadienyl manganese tricarbonyl) is an antiknock additive for unleaded gasoline, which is now required for cars equipped with catalytic converters. Because of its effectiveness, MMT is economically attractive compared with achieving antiknock quality by refinery processing. Use of MMT in gasoline at a concentration of 0.125 g of contained manganese per gallon provides, on the average, about 2 road octane numbers. Compared to processing, this could represent a savings in crude oil of about 1%. Like other antiknocks, the economic attractiveness of MMT is greatest at low concentrations. Extensive road and dynamometer engine tests have shown that use of MMT in the recommended concentration range is compatible with general aspects of car operation--octane number requirement, exhaust valve and spark plug durability, and exhaust gas recycle for NOx control. Moreover, beneficial effects in exhaust valve guide and seat wear have been observed with MMT in some tests.

This oil category was driven by two new cooled exhaust gas recirculation (EGR) engine tests operating with 15% EGR, with used oil soot levels at the end of the test ranging from 6 to 9%. These tests are the Mack T-10 and Cummins M11 EGR, which address ring, cylinder liner, bearing, and valve train wear; filter plugging, and sludge. In addition to these two new EGR tests, there is a Caterpillar single-cylinder test without EGR which measures piston deposits and oil consumption control using an articulated piston. This test is called the Caterpillar 1R and is included in the existing Global DHD-1 specification. In total, the API CI-4 category includes eight fired-engine tests and seven bench tests covering all the engine oil parameters. The new bench tests include a seal compatibility test for fresh oils and a low temperature pumpability test for used oils containing 5% soot. This paper provides a review of the all the tests, matrix results, and limits for this new oil category.

This paper presents the results of an investigation cooperatively undertaken by Esso Research and Engineering Company and Ethyl Corporation to determine whether the hydrocarbon-type effect observed in road antiknock studies of gasolines is independent of other fuel properties over and above laboratory octane numbers. For this study, 51 finished gasolines were carefully blended from 57 base stock components to provide controlled levels of those major fuel properties which affect road performance. The controlled properties were Research octane number, sensitivity (RON minus MON), ratio of aromatics to olefins, tetraethyllead content, octane-number distribution in the fuel's boiling range, boiling-range location of the unsaturated hydrocarbons, and sulfur content. A unique feature of the blending scheme was the formulation of blend pairs, in which all but one of the major fuel properties were essentially equal.

The purpose of this paper is to demonstrate our success in taking advantage of model-based development tools and auto-code technology to accelerate the typical life cycle development of powertrain software. In particular, we applied the technology as a clean sheet approach to Visteon's third generation Electronic Throttle Control system. In the process of applying model-based development and 100% auto-code, we identified various pitfalls and created solutions to overcome the gap between technology and development process during each phase of the entire software development life cycle. We will share our lessons learned during the requirement, design, implementation, and validation stages.

Reliable prediction of the radiated noise due to the air pressure pulsation inside air-intake manifolds (AIM) is of significant interest in the automotive industry. A practical methodology to model plastic AIMs and a prediction process to compute the radiated noise are presented in this paper. The measured pressure at the engine inlet valve of an AIM is applied as excitation on an acoustic boundary element model of the AIM in order to perform a frequency response analysis. The measured air pressure pulsation is obtained in the crank-angle domain. This pressure is read into MATLAB and transformed into the frequency domain using the fast Fourier transform. The normal modes of the structure are computed in ABAQUS and a coupled analysis in SYSNOISE is launched to couple the boundary element model and the finite element model of the structure. The computed surface vibration constitutes the excitation for an acoustic uncoupled boundary element analysis.

In designing fuel economy oils, two useful approaches are reduction of viscosity and incorporation of friction reducers. To achieve viscosity reduction without incurring problems of high oil consumption and possible interference with catalyst or oxygen sensor performance, the use of part-synthetic lubricants can be helpful. In this way, oil volatility (therefore oil consumption) is reduced and fuel economy is improved without incurring engine operating penalties. Friction reducers also can be used to improve fuel economy. The combination of these approaches furnishes the benefits of both. Laboratory and road testing of such combinations show important fuel economy benefits in normal vehicle operation, greater than those achievable from either approach alone. In addition, all other engine performance requirements are completely met. This advance in engine oil formulation technology, which opens up new possibilities to both vehicle manufacturers and consumers, is being further pursued.

Traditionally fog lamps use halogen filament light sources. With the emergence of high brightness white LEDs, it is now possible to develop automotive forward lighting systems with LED light sources. Six LEDs are shown to be sufficient for the implementation of a European fog lamp using a faceted reflector optical approach. Each reflector together with the LED light source forms a modular element. The optical parameters of two different lamp designs are compared and correlation between the simulation and prototype measurements is shown. Further, additional forward lighting functions can be implemented through the use of additional elements.

Commonly, a significant event is detected when a normally stable engine parameter (ex. sensor voltage, sensor current, air flow, pedal position, fuel level, tire pressure, engine acceleration, etc.) transiently exceeds a calibrated detection threshold. Many implementations of detection thresholds rely on multi-input lookup tables or functions and are complex and difficult to calibrate. An approach is presented to minimize threshold calibration effort and complexity, while improving detection performance, by dynamically computing thresholds on-line based on current real-time data. Determining engine synchronization without a camshaft position sensor is presented as an illustrative application.

This paper discusses our experiences on the implementation and benefits of using the Hardware-In-the-Loop (HIL) systems for Powertrain control system software verification and validation. The Visteon HIL system integrated with several off-the-shelf diagnostics and calibration tools is briefly explained. Further, discussions on test automation sequence control and failure insertion are outlined The capabilities and advantages of using HIL for unit level software testing, open loop and closed-loop system testing, fault insertion and test automation are described. HIL also facilitates Software and Hardware Interface validation testing with low-level driver and platform software. This paper attempts to show the experiences with and capabilities of these HIL systems.