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Viewing 70801 to 70830 of 104295
1988-09-01
Technical Paper
885148
C. D. de Boer, D. W. Grigg
In view of the impending exhaust emission and fuel quality legislation in Europe, the motor industry is faced with developing engines giving low levels of HC and NOx emissions while operating on unleaded gasoline and retaining good fuel economy. Ricardo have designed an advanced open chamber combustion system with vertical in-line valves, designated the “Nebula” combustion chamber. The design is based on converting the intake generated air motion into turbulence near to TDC, thus producing a fast burn characteristic. Initial development was carried out on a 86 × 86mm Hydra single cylinder research engine, where spark plug position and intake port swirl ratio were optimised. This work demonstrated potential of the “Nebula” concept which showed a considerable reduction in HC and NOx emissions at part load. The “Nebula” combustion chamber has been applied to a 1.35 litre engine in a European vehicle.
1988-09-01
Technical Paper
885024
Ge Anlin, Wu Jinqiu, Lin Mingfang, Gue Wanfu
In the paper, by practical dynamic process instead of steady assumption, mathematical model in a meticulous way and the overall optimization for the design variables, it is applicable to determine the optimum performances for power transmission system. At the same time, according to typical driving cycle for the vehicle fuel economy is taken as objective function and the dynamic performance as restraint so that the rational coordination of fuel economy and dynamic one can be achieved. Finally, the optimum result shows that it is in a closs agreerment with the test result.
1988-09-01
Technical Paper
885026
Jean Cusset
Over the last ten years the PEUGEOT SA group has developped several multifunctional parts in plastics: the front end frame in 42 % glass SMC of the new PEUGEOT 405 shows a high degree of multifunctionnality: more than 15 components are fitted on this panel, among them the bumper, the headlamps, the front grill, the radiator etc… The part has a structural function as it closes the front end of the car body; it works as a fixture for the fitting of the equipments and thus improves the overall aspect quality of the vehicule front end. This paper describes the prototype phase (material, simulation tests), the most important production steps at the custom moulder plant (finishing operations by laser, automatic inserts fitting) and finally the ultimate operations in the production plant of Automobiles PEUGEOT: fitting of accessories (mainly by robots) and assembling on car body.
1988-09-01
Technical Paper
885022
M. W. Dunkley, D. Speranza, J. E. Stainton
Mechanical transmissions for heavy-duty vehicles up until recently could be classified into one of two categories differentiated by the shifting effort required. In one category, the shifting effort is predominantly physical and the force applied to the shift lever is used to synchronize the gears to be engaged, thereby reducing the mental effort required to make a gear change. Transmissions of this type are well known as synchromesh transmissions which employ heavy-duty synchronizers. In the other case, the shifting effort is predominantly mental in that by correct control of the engine speed and clutch brake on the part of the driver, relatively low forces were required to be applied to the shift lever to change gears. Transmissions of this type are well known as non-synchronized or constant mesh transmissions. The arrival of electronics on heavy-duty vehicles has recently opened up a whole new category of transmissions, a category in which shifting effort is truly reduced.
1988-09-01
Technical Paper
885023
Trudy R. Weber
A system optimization approach has been developed to configure and analyze hydraulic energy-storage based propulsion systems. The powertrain synthesis problem is formulated as an optimization problem of minimizing the engine fuel rate over a finite time interval. The solution process is driven by energy management and control strategies, which determine the transmission ratio and the hydrostatic pump/motor unit displacement such that the engine can be operated at its minimum fuel rate. This approach has identified a powertrain consisting of an automatic four-speed transmission plus a hydrostatic pump/motor unit and accumulator used to regenerate and store vehicle kinetic energy. Within the limitations of our analysis, the hydraulic hybrid system has shown potential for significant improvement in fuel economy over a conventional system.
1988-09-01
Technical Paper
885021
Dušan O. Gruden, Günther Höchsmann
The extensive research and development efforts undertaken to improve the characteristics of the combustion engine have repeatedly identified fuel as being one of the hampering factors. Gasoline and Diesel fuel, both being crude oil derivatives, are responsible for the breaking up of the engine family as a whole into Otto and Diesel powerplants. The dream of a “multi-fuel-engine” tolerating any of the fuels available on the market cannot be realized due to the various severe demands modern passenger cars have to meet. One of the possibilities deals with a “flexible fuel” vehicle able of identifying various gasoline/alcohol mixtures and burning them with greatest possible efficiency while meeting the legal requirements. Another approach under investigation is the “adaptable manufacture” of engine components: Depending on the types of fuel available on the market both Otto and Diesel engines will be produced on the same production equipment.
1988-09-01
Technical Paper
885020
Nils-Olof Nylund, Juhani Laurikko, Ari Juva
A low ambient temperature increases wear and fuel consumption in vehicle engines. The startability of the engine and the start-up of lubrication are highly dependent on the type of engine oil (mineral, semisynthetic, synthetic), whereas fuel consumption depends more on the engine type and driving conditions. The research work in a special cold chamber equipped with a powerful cooling system has so far involved three gasoline engines and two diesel engines. One gasoline engine was also tested in combination with an all-mechanical transaxle. Tests were carried out within the temperature range of +20…−30 °C using different engine lubricants in order to evaluate both lubrication during the initial start-up and fuel consumption during a test period of 30 minutes. Engines were run under both constant and cyclic load. Effects of auxiliary electrical block and oil sump heaters were also studied.
1988-09-01
Technical Paper
885019
Hajime Ise, Hiroshi Hirano, Nobuyoshi Nozaki, Haruo Takizawa, Mitsuo Tamanouchi, Isao Nakajima
A cold flow index of automotive diesel fuels in Japan has been investigated, from the view point of the fuel system configuration of diesel vehicles, by a task force study organized by the Japan Petroleum Institute. The results of the study are as follows; 1. The Cold Filter Plugging Point (IP 309, JIS K 2288) was found to be an excellent index of cold flow properties of automotive diesel fuels for the operability of Japanese diesel vehicles. 2. CFPP values for cold operability limits for the fuels at minimum ambient temperatures were established in the range from −5° to −30°C. 3. A rig tester simulating the cold operation of the most sensitive vehicle at ambient temperature was very effective in evaluating the cold flow properties of automotive diesel fuels.
1988-09-01
Technical Paper
885037
Karl-Heinrich Schönfeld, Karl-Heinz Hesse
Improved technology, including the application of electronic components, led to the development of a new generation of air suspension systems for passenger cars. These systems have now been introduced into the marketplace. The reasons for air suspension systems, the design criteria of their components and their control will be described. Details will be given of the air supply-unit compressor + air dryer), of the air distribution components (pipes, valves) and control components sensors, electronic control unit).
1988-09-01
Technical Paper
885034
Shoichi Sano, Yoshimi Furukawa, Takashi Nihei, Masaru Abe, Mitsuya Serizawa
The rear wheel control technique for the Honda Steer Angle Dependent four wheel steering system (Honda 4WS) is based on a combination of two methods, of which one controls the rear wheel steer angle without delay by using only the steering wheel angle for control input, and the other controls the rear wheel steer angle as a nonlinear function of the steering wheel angle. These methods have been adopted to efficiently reduce a delay in lateral acceleration response during maneuvers in straight road driving by generating lateral force at the rear wheels as quickly as possible, and, in addition, to offer a higher yaw responsiveness when making sharp turns. This report tries to demonstrate the effects of these two control methods from the viewpoint of dynamics and then, based on a quantitative analysis with mathematical models, it compares these and other control methods with respect to their effects on steering responses.
1988-09-01
Technical Paper
885033
T. C. Chatterley
The paper describes the earlier research on cam and cam-follower materials carried out by MIRA using a specially developed, test machine. A table summarising the results of this earlier work is given. The use of the same test machine to assess the performance of lubricants when used in conjunction with standard components is also mentioned. The main part of the paper describes more recent work involving certain new processes and two ceramic materials as applied to cams or cam-followers. The results indicated that some of these processes or materials, particularly silicon nitride ceramic, can perform well in the cam and cam-follower situation. The results, particularly those for the very hard materials, were found to be influenced by surface finish, whilst the type of lubricant was found to affect the performance of chilled cast iron cams running against the ceramic materials.
1988-09-01
Technical Paper
885031
Akira Oguri, Hisanao Totii, Tetsuhiro Hosokawa, Masahrko Nakada
A theoretical model has been developed which simulates piston movement in the engine cylinder. Piston movement is calculated by a precise step-by-step method in order to accurately obtain the intensity of piston-bore impact. The intensity is defined by both impact force and energy. It is shown that this model gives good agreement with measured piston movement. The impact intensity predicted by this model is confirmed by measuring the cylinder wall vibration. Piston side force obtained by this model gives a good prediction of piston-skirt wear. An example which shows the reduction in oil consumption improvement of the piston movement is also demonstrated.
1988-09-01
Technical Paper
885030
Satoshi Sugiyarna, Tetsu Kachi, Nobuaki Takahashi, Hiroshi Sannokyo
An interior layout plan in the development of a new car is indispensable for investigation of safety, operability and comfortableness of a car. For efficiently carrying out the interior layout plan, it is essential to keep as data base and use analytically information on profiles of a large number of cars. We have developed an automatic measuring device utilizing a laser beam for interior dimensions. This paper describes a newly developed Laser Interior Profile Scanner (LIPS), which is a very small and light device utilized a laser diode as a measuring light source. The principle of the measurement employed a polar coordinate system, a coordinate value of a measuring point was determined by a distance and laser scanning angle. LIPS has been developed for non-contact, high precision within 1 mm and high-speed measurement of narrow and complicated interior profiles in cars.
1988-09-01
Technical Paper
885029
David D. J. Tao, Ronald C. Malec, Tim G. Adams
A series of vehicle tests were run in the climate control wind tunnel, at - 18°C (0°F), to characterize the engine warm-up and heat rejection from a 2.3 liter gasoline engine powered Ford Aerostar. The objectives of the tests were to identify and quantify the “waste heat” and to determine how passenger compartment heating could be improved through better waste energy management. It was found that approximately 57 percent of the fuel energy was dissipated as waste heat. More than 30 percent of the fuel energy was lost due to convection and another 20 percent was dissipated in the exhaust gases at the simulated low speed, light load driving conditions. Recovery of a portion of this energy coupled with modifications to the cooling system should lead to greatly improved heater performance.
1988-09-01
Technical Paper
885028
Guy Courbon
The evolution of the automobile engine is threatening to make it impossible, some day, to heat the passenger compartment properly. Current developments, especially improvements in efficiency, are reducing what the automotive engineer regards as a loss, but what constitutes for the heating engineer a resource with which to create a comfortable interior environment. Under these circumstances, maintaining proper heat levels requires complementary equipment.
1988-09-01
Technical Paper
885027
Claus Razim
The multitude of technical papers, articles in newspapers and publications describing research policy points at the importance of materials research, development and testing, materials technology in general, for any kind of future technological progress. In this context the necessity to support mostly revolutionary developments is mentioned very often, resulting in the danger to neglect evolutionary developments of known and conservative materials. The technological challenge in materials consists not only of inventing new materials but to a large degree of the research of the as yet unknown or not sufficiently known relations between the material and the field behavior of a constructional part on the one hand and material and behavior in the production process on the other hand. The optimation of these relations leads finally to the industrial use of such materials in a worldwide competitive market.
1988-09-01
Technical Paper
885044
H. F. Mahmood, A. Paluszny, Y. S. Lin
Development of a systematic computer method to determine the energy absorption in a general collapse mechanism is the main objective of this paper. Models of several collapse modes have been developed to estimate the amount of energy absorbed in an automobile body structure during collision. These models will aid design of structural components for crash energy management and facilitate sensitivity studies to check the robustness of alternate concepts. Bending strengths and collapse modes of vehicle structural members are presented. Mathematical models based on the section collapse mechanism are developed. The shape of collapse mechanism shows to play a significant role in determining the energy absorption during automobile collision. A strip method approach is used, in which the cross-section under consideration is divided into a number of plate sub-elements (“strips”). The system finds the stresses in each strip and identifies the sub-element which initiates buckling.
1988-09-01
Technical Paper
885045
Jiang Shubin
This study shows that after adding niobium and nitrogen into the cast iron, Nb(C.iv) compound in the matrix structure appears and free nitrogen and oxygen are fixed. Besides, more clear grain boundary, increased amount of eutectic cell, and improved mechanical properties of the cast iron both in room and high temperature conditions are obtained. Due to the higher heat-resistance, melting point and microhardness of the Nb(C.N) compound, the antifusion-friction and abrasive wear resistance properties of the Nb-N sleeve are improved significantly and its service life is prolonged. The service life of Nb-N sleeve is aboout 40 percent longer than that of boron cast iron sleeve. By applying Nb-N sleeve, the overhaul mileage of gasoline engine used for medium load truck will be sore than 350 thousand kilometers. This means quite a benifit to endusers.
1988-09-01
Technical Paper
885046
Neil A. Schilke, Roger D. Fruechte, James H. Rillings, Steve M. Rohde
The existence of the computer coupled with the rapid development of analytical engineering techniques has made it possible to design complex systems which are different and better, and to do so in a manner that is more efficient. Examples from the aircraft industry include hypersonic airplanes in which the fuel serves as a coolant to heat sensitive frame components, and the frame serves as part of the engine. Thus, design changes to any single part have cascading effects on the entire Bystem. This leads to extreme complexity in the design process and requires extensive computational resources and sophisticated computer techniques to proceed in a rational manner. For example, large scale systems theory and multi-level optimization are some of the approaches applicable to this class of design problems.
1988-09-01
Technical Paper
885047
H.-H. Braess, R. Stricker
A design model for parametric systems is presented based on the example of vehicle design. The formal construction of the model is equivalent to an “expert system using conventional means”. The knowledge base comprises algorithmic and non-algorithmic sections. It can store knowledge from different sources (designer's know-how, mathematical/physical simulation etc.). A graphic interactive user interface allowes to set up the enquiry, which is taken by the “solution engine” to compile a reply at the user interface using an optimum target-oriented search technique on the knowledge base. In addition to the user interface, also a graphic interactive consultation and explanation component is available to support the user in setting up consistent questions and in interpreting the results. Practical application of the design model is shown with the aid of a simple example.
1988-09-01
Technical Paper
885039
R. J. Woolgar
With the present day requirement to verify the performance of complex systems and to facilitate their development, modelling those systems will pay an increasing role in the future. To this end a full ride and handling model of a vehicle was developed. The model includes front and rear suspension with flexible anti-roll bars, steering, engine and its mounting system and the suspension damper control system. The major significance of this model was the addition to the simulation of the microprocessor control of a variable element within the system which was a new step in this type of modelling technology. Thus the effect of control strategy changes and of time delays caused by signal conditioning, software loop times and actuator response could be assessed.
1988-09-01
Technical Paper
885040
Gerhard Mauk
Advances in automobile technology mean that ever higher standards and better performance are expected of tyres, in recent years especially optimized performance charakteristics and run-flat capability. Previous development of tyres with run-flat capability failed to fulfill all requirements because present tyres are seated on the radially located outer surface of the rim flange. Using a new design with tyre seat on the radially located inner surface of the rim flanges CTS (ContiTyreSystem) can met all major demands. This tyre is wrapped around the run flange and is held in place on an inward facing rim flange. This design brings many benefits for the tyre's performance features and runflat capability is attained. Even after pressure loss the tyre will not come off the rim in any driving situation and runs on the support surface of the rim. In this way a vehicle can be driven with a deflated tyre for several hundred kilometers.
1988-09-01
Technical Paper
885042
Tsugio Ikeda, Hiroshi Kimura, Osamu Shiraga
The vehicle interior cover material requires good cloth hand and sewability with no wrinkle-and-slack to produce a superior quality. Usually, the evaluation for the cloth hand of cover materials depended on subjective judgement, and for the sewability has been relying on the experience of an expert. Therefore, an objective evaluation has not been performed. As the result, there were some cases where this matter has become a subject of discussion at planning and producing. In this research, the correlation to the usual measuring method, evaluation, and sewability was performed by measuring the very subtle values of cloth mechanical and surface properties. The results in outline are as follows; The test precision has been improved by applying the new evaluation method. The cloth hand for each kind of cover materials has been quantified by applying the mechanical properties.
1988-09-01
Technical Paper
885043
Takeshi Mottate, Yoshio Kitazawa, Junji Fujiwara, Ryoichi Nomi, Noboru Urayama
A variety of techniques are employed by automobile manufactures in an effort to assure the anti-corrosion performance of thin product. One of the most effective techniques is to use surface-treated steel sheets for making vehicle body panels. Durasteel features a double layer construction, in which a thin organic film is applied over a zinc-nickel alloy layer which provides good protection against base metal corrosion. Durasteel sheets possessing a bake hardening property have started to be applied to outer body panels in recent years. Until recently, it was impossible give paint-coated steel sheets the bake hardening property of Durasteel. In this investigation, a new resin coating has been developed which can be baked at low temperature without sacrificing its corrosion resistance. The key technological issues encountered in the development work were to select the right resin material and to find the best method for applying chromate treatment to the alloy surface.
1988-09-01
Technical Paper
885052
Guntram Huber
The characteristics of heat-absorbing glass for passenger cars are described with regard to climate perception and visibility of the driver, both of which are important aspects of active safety. Such modern types of glass reduce the transparency to heat and at the same time maximise light in the visible spectrum. To be in a position to quantify the advantages and disadvantages in the visible spectrum as regards transparency, dazzling, reflectance and diffused light, practical road-test runs were carried out on the same public roads under different conditions in light and climatic environmental. The tests comprised physico-technical, physical and psychological data with regard to driving behaviour of and strain on the drivers. The results confirm the predominance of advantages of heat-absorbing glass and provide, indications as to optimising the side and rear windows by increasing the degree of heat-absorbing.
1988-09-01
Technical Paper
885055
G. G. Lim, A. Paluszny
This paper provides an overview of the Side impact Research program conducted by Vehicle Methods and Components Department of Ford Motor Company over the past three years. A simple spring-mass computer simulation model is developed for predicting crash behavior of the body side structure of a vehicle impacted on its side by another vehicle. The model was used in determining the degree of structural reinforcement required to effectively reduce body side intrusion of a compact size vehicle. Exellent agreement between the predicted and test results was obtained and the effectiveness of structural reinforcements in reducing occupant cushioning requirement was demonstrated.
1988-09-01
Technical Paper
885053
Leonard Evans
This paper reviews three studies performed by the General Motors Research Laboratories which address different aspects of how age and sex affect injury rates in severe traffic crashes. All three studies use data from the Fatal Accident Reporting System, a file maintained by the National Highway Traffic Safety Administration. This data file gives information on all fatal traffic crashes in the United States occurring since January 1, 1975. The first study found relationships between risk of a fatality from the same physical impact and age and sex. The second study examined, as a function of sex and age, involvement rates in crashes in the same high severity range by combining the results of the first study with raw fatality rates in crashes. The third study included an examination of traffic fatalities relative to other causes of death. Almost half of all deaths to 18-year olds are due to traffic crashes.
1988-09-01
Technical Paper
885056
Charles A. Amann
The engine is often considered to be a subsystem of the automobile, along with the drivetrain, chassis, suspension and body. The spark-ignition engine is itself a system, however, comprised of subsystems managing such necessities as fuel, air, exhaust, ignition, cooling and lubrication. The sophistication of the modern automotive engine fosters the development of engineering specialists, but the specialist must never lose sight of the relationship of his particular subsystem to the others, for inattention to the interfaces between subsystems leads to an inferior product. To illustrate the need for maintaining a systems viewpoint, issues surrounding the interface between the piston and rings and the cylinder wall are reviewed.
1988-09-01
Technical Paper
885048
B. Cohen
The extremely rapid development of the use of scientific computing in car design (75 per year) required the installation of a CRAY XMP supercomputer at PSA. This machine has doubled the group's overall computing power and has multiplied the power of the central plant tenfold. Computation of structure using finite elements with 50 000 degrees of freeedom, which was previously processed on an Amdhal 5860 in 40 minutes, at night, can now be processed in 5 minutes, during the day. This means that the structure can be optimised more efficiently, if there are means available, to modify rapidly the mesh. In addition, models can now be made of new phenomena in the fields of fluid mechanics, combustion, accoustics and the mechanics of non linear structural analysis. By computing the dynamics of gases in the manifolds and taking into account finer hypotheses (threee-dimensional viscous and transcient), flow round the valve and filling of cylinder can be simulated.
1988-09-01
Technical Paper
885049
Tomokazu Tokuda
There are two major themes that characterize the technological advances seen in the car during the '80s. One is the improved functional performance of the various units making up the car, which has been achieved through the application of advanced control technology. The other is the pursuit of performance in each vehicle unit which matches the sensibilities of the occupants. In future vehicles envisioned for the '90s, all of the individually enhanced units will be integrated into a total vehicle system. The basic viewpoint for fusing the different units together will be found in “human sciences.” Instead of merely combining the various units to achieve multiple benefits, the entire vehicle will be engineered to suit the occupants' total sensibilities. In addition, the vehicle concept will be treated in terms of its total relationship with social activities and individual lifestyles. The newly released Nissan ARC-X embodies this near-future vision of the car.