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This paper discusses the effect of various individual and combinations of thermal Stabilizers and their effect on polymer properties. We will show the effect on initial molded properties with various stabilizers, and how the proper balance of stabilization can enhance the long term heat aged properties on both ASTM test specimens and also on actual large molded part performance. Physical Properties investigated are those of Izod, multi-axial impact, tensile and flexural properties over a range of aging times and temperatures.

The purpose of this paper is to review current laboratory test methods for conducting artificial weathering of vinyl/foam composites as specified by major automotive manufacturers for instrument panel components. Critical test parameters for each method, including spectral irradiation (ultraviolet, visible, and infrared components), light/dark cycles, ambient temperatures, black panel temperatures, and moisture levels are reviewed. The mechanisms by which these test conditions are controlled are discussed. The subjectivity of criteria used to judge whether test results are considered passes or failures are discussed and alternative quantitative methods suggested. The need for uniform weatherability test standards throughout the automotive industry is considered in terms of the implications on automotive supplier material development efforts.

In 1985, a draft standard procedure was issued by the International Standards Organization (ISO/DIS 6452) for evaluating the fogging propensity of automotive interior trim materials using an oil immersion test apparatus. Our evaluation indicates that this procedure fails to take into account a number of variables, the control of which are crucial to the attainment of rational test data. Results of experiments conducted to investigate the effects of these variables are presented and, based on our findings, an improved method for measuring and specifying the fogging behavior of interior trim materials is proposed.

Transient control of speed and torque on the testbed is becoming increasingly important for modern engine development. This paper describes the application of a modern control technique, Generalised Predictive Control (GPC) to this problem. By using system identification, coupled with the GPC design algorithm, the controller is automatically tuned by a computer. The best performance can then be obtained for each installation. The results presented show that, on a testbed with a standard eddy current dynamometer, tight control of transient speed and torque can be achieved using these techniques. This enables transient testing facilities to be made much more widely available.

A microprocessor controlled lubricating oil cooling system of truck diesel engine was designed to minimize the sump oil temperature fluctuation during start-up and nonsteady engine operations. Model reference adaptive control method is utilized in the control system design. The analysis involved in the design of the microprocessor controlled oil cooling system, and the applications of a special vehicle-engine-cooling system (VEC) computer simulation code in the implementation and testing of the model reference adaptive control strategy are described. Using the VEC simulation code, the performance of the microprocessor controlled oil cooling system and the conventionally controlled oil cooling systems were compared for the ATB, temperature disturbances, and cold weather transient tests. An explanation of each test, as well as a review of the results of comparison tests are presented.

A review of electronic diesel governor design objectives is given. Voest-Alpine Automotive's (VAA) design guidelines are explained, and a new governor type 4 is presented. The 185×142×47 mm3 unit (appr. 1/3 the size of comparable 1987 vintage gear) is applicable to most injection pumps using linear or rotary actuators and associated control valves. It features all functions required in high performance diesel vehicles. An exceptionally low IC count of seven (no custom designs), a power dissipation of typically 6 W, advanced CMOS and VMOS circuitry and the unique multi-microcomputer architecture MµCA (R) ensure safety, reliability as well as the future addition of complex functions. A second-generation programming computer is described and data taken from typical applications are shown.

Major advances are being made in engine hardware, control theories and microcomputer technology. The application of advanced control and monitoring techniques to engines should enable them to meet all the restrictions imposed upon them while they operate to their full potential. Variable geometry turbocharging of automotive diesel engines is a good example of a case where the control implications need to be considered carefully. This paper reports a technique for developing the dynamic characteristics of turbocharged diesel engines with variable geometry turbine and compares the results with measurements obtained on an engine. It is the first step in the design process for a true, dynamic, multivariable controller. Most current systems are simply scheduling devices with little understanding or consideration of possible interactions between various control loops. A non-linear simulation model for a turbocharged diesel engine was used to investigate the performance of the engine.

A numerical optimization technique has been applied in order to obtain the optimum level of some design variables of the diesel fuel injection nozzle. A description of the optimization procedure is provided together with a discussion of the physical and mathematical flow model used. Sample applications of the optimization procedure addressing design of a fuel injection nozzle consideration along with comparisons among three different fuels are presented. The fuel injection mean rate, the diameter of the injection cavity, and the diameter of the injection orifice were used as the objective functions in different aspects of the optimization procedure. Chosen design variables were: the angle of the needle tip, the diameter of the nozzle injection cavity, and the injection orifice diameter. Some constraints characterizing the operating conditions of the injection nozzles were taken under consideration.

This paper presents a new series of Timing and Injection Rate Control Systems: AD-TICS and P-TICS, for medium and heavy duty DI diesel engines. These TIC systems are equipped with a new concept of variable pumping rate, which is realized by controlling the prestrokes of the pumping elements. First, the outline of these new injection systems will be briefly described, showing the basic constructions and the range of applications, with some diagrams and schemata. Secondly, the injection characteristics of the jerk injection system will be clarified by simulation calculations, comparing the pump-pipe-nozzle with the unit injector. Calculation results will enable a comprehensive interpretation of the behavior of such injection characteristics as injection pressure, duration, etc., ie, in accordance with the pumping rate, dead volume, and nozzle orifice area, etc.. Furthermore, detailed characteristics obtained using AD-TICS and P-TICS will be shown.

This paper describes the methods of operation and functions of advanced fuel injection controls, and the results of engine testing for the “Learning Control”, a function which was developed to control diesel engines that makes the most of the flexibility found in software used for electronic control. In-depth of study of the “Learning Control” function, confirms that this function can provide stability in engine performance by automatic compensating for injection quantity deviation in fuel injection pump operation. This paper also outlines concepts for insuring the safety of system operation during the “Learning Control” stage.

The extensive reliability engineering program performed during the development of the DDEC I and DDEC II systems is described. This program insured that established reliability goals would be met and objectively demonstrated before the DDEC systems were released to the marketplace. Reliability goals representing the most stringent customer expectations were established at the program start. Then a formal reliability growth test program was performed that included running on engine dynamometers, at selected domiciled truck locations and in a broad range of customer revenue service vehicles.

The Model 85 is an integral overdriven unit with a lockup clutch torque converter. Of rear drive configuration, the transmission targets 2.0 to 5.0 litre passenger cars and light trucks. The conventional mechanical arrangement is driven via a microprocessor-based control system which utilizes throttle position, engine speed, transmission output speed, transmission sump temperature, gear selector position, and performance/economy selector inputs to control all shift feel and shift schedule aspects. This control approach results in improved transmission performance with reduced package size (dry weight of 70 kg).

The operating characteristics of the check valve in the clutch piston of an automatic transmission have a great effect on the shifting performance and durability of the developed clutch package test rig was used to visualize the flow and make pressure measurements in the vicinity of the check valve. The results indicate that the strength of the vortex just in front of the check valve strongly influences the opening and closing hydraulic pressure of the valve. It was also found that the vortex causes a pressure drop, which is related to the rotating speed of the clutch piston, oil volume discharged from the check valve and valve geometry. These results were used to design an improved check valve which provides a suitable oil pressure curve for achieving smoother shifting.

Recently, there has been a significant growth in the variety of data acquisition systems used in vehicle testing in the auto industry. Although this has improved testing productivity significantly, it has resulted in the growth of systems that are incompatible with the engineer's work-station. This paper describes an integrated design methodology and the features of the Vehicle Data Acquisition System (VDAS) developed by the Ford Research Staff and used by various Ford Divisions for vehicle testing. The system consists of an industrialized IBM-PC/AT clone that is powered by the car battery. It has menu-driven, user friendly software with voice command capability, and has the ability to run data acquisition, analysis and graphics in the vehicle. This system was developed by maximizing off-the-shelf software and hardware while minimizing customization.

Automotive development programs require the on-board collection and analysis of data originating from a wide variety of sensors. This paper describes an in-vehicle, general purpose data acquisition and display system that provides a mechanism to acquire, display, and analyze multiple channels of input sensor data. Development engineers can view multiple channels of data in real time and analyze the data immediately afterwards inside the vehicle. Thus, design decisions can be made on the spot instead of waiting for later analysis back at the office. This valuable engineering tool is a rugged, compact, low power unit, and is easy to install and use.

The high compression ratio in Diesel engines leads to pronounced minima of the flywheel angular velocity at idle conditions. The minima coincide with the zero crossover of the torque acting on the crankshaft; that is when a piston is in the TDC position. The ring gear of the flywheel with one marked tooth is used as an angular scale. The ring gear is not precise enough to observe the minima of angular velocity directly, but the “center of gravity” of the peak below the mean angular velocity correlates with the TDC with an error less than 0.5° CA. A Software TDC Generator is proposed, that calibrates the angular position of the marked tooth at idle conditions, and generates continuously an output pulse (TDC-pulse) at a given angular position of the crankshaft.

Homogeneous coordinate-transformation matrices are used to analyze a Cardan-type universal joint whose input and output shafts do not intersect because of mounting tolerance errors. It is found that such mounting errors induce double-frequency axial motion at the output joint of magnitude comparable to that of the error. To avoid this sliding motion it is important that the offset between the input and output axes which results from mounting errors be held to as close a tolerance as is possible.

The torque converter is a very complex turbomachine. Its geometry is highly three-dimensional, the working fluid is viscous oil, and it operates under a wide range of flow conditions. However, its hydrodynamic design technology has advanced very little during the past few decades. The design procedure has been based greatly on the use of the cut-and-try approach. The use of such an approach may satisfy the design requirements in terms of diameter, axial length, and K factor, but it may never lead to an optimized design for any given application. In addition, it has been proven to be too costly and time consuming. The current design tools need to be upgraded in order to significantly advance the hydrodynamic design technology. A review of the technology needs in the areas of internal flow, blade design, and performance is presented. First, the three-dimensional internal flow field and the physical mechanisms of the internal flow losses are described.

The emission development performed to meet 1988 Federal and California emission standards with a four-stroke direct-injection V-8 diesel engine of 8.2L displacement is described. On the naturally aspirated engine the major concern was meeting particulate and lug smoke standards at low NOx levels. Acceleration smoke and particulate emission reduction was necessary on the turbocharged engine. The performance and emission goals were met by modifying the unit injectors and pistons of both naturally aspirated and turbocharged engines.

In Japan, about 5.6 billion tons of freight are transported annually and 90% of this figure is supported by trucks. Among them, the heavy vehicles of GVW 20ton are employed as one of the main means of such transportation and they are produced about 40,000 units annually. For these trucks, over 80 types of diesel engines have been developed during the past 20 years. Today, there are more than 30 domestic types. The engine displacement ranges from 8.8 to 18.0 liters and the maximum output spreads from 270hp (199kW) to 380hp (280kW). The naturally aspiration type occupies 70% and the turbocharged or turbo-intercooled type takes the remaining portion. The authors present the design concept and the technical background which are involved in the above-mentioned engines. They also describe the technology which concerns combustion, gas exchange, construction, electronic control, etc. and the ‘total power system’ (some simultaneously managing system) formulated to realize such engines.