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Currently, advancements in Rapid Prototyping (RP) technologies have led to considerable amount of research activities and has been playing a major role in the area of tooling development for which Rapid Tooling (RT) term was coined. While rapid prototyping techniques are employed to make prototype tools, the basic idea of the rapid tooling is to produce prototype and zero series parts by using prototype tools so the parts truly represent the future production. This paper will present an evaluation of a RP and RT technique in developing tools (punch and dies) for sheet metal forming, which had been manufactured and tested. Both punch and die have been manufactured by combining Stereolithography (SL), RP technique, with nickel electroforming process. The stereolithography technique that had been utilized in developing models for the tools had been built with modeling pattern called Accurate Clear Epoxy Solid (ACES).

There is a definite trend toward the increasing use of “Glass Encapsulation Technology” in the automotive industry. In this technology a glass object such as a window is placed within a mould and an elastomer is injected around the window giving a tight sealing system. A wide variety of materials are currently used as the sealing materials in either static or semi-static encapsulated glazing systems, including a wide range of “elastomers”. New thermoplastic elastomer compounds are being developed that are characterized by their consistent properties; including high melt-fluidity, very good surface appearance, sealing properties, and resistance to weathering. Compound performance is highly dependent on formulation variables as well as the chemistries of the base materials. KRATON® SEBS polymers1 are block copolymers of styrene and ethylene/butylene.

The objectives of the present work are to investigate the regulated and unregulated (particle) emissions of a classical and modern 2-stroke and a typical 4-stroke scooter with different ethanol blend fuels. There is also comparison of two different ethanol fuels: pure ethanol (E) *) and hydrous ethanol (EH) which contains 3.9% water and is denatured with 1.5% gasoline. Special attention is paid in this research to the hydrous ethanol, since the production costs of hydrous ethanol are much less than those for (dry) ethanol. The vehicles are with carburettor and without catalyst, which represents the most frequent technology in Eastern Asia and offers the information of engine-out emissions. Exhaust emissions measurements have been performed with fuels containing ethanol (E), or hydrous ethanol (EH) in the portion of 5, 10, 15 and 20% by volume. During the test systematical analysis of particle mass (PM) and nano-particles counts (NP) were carried out.

It has been long established fact that fuel economy is a key driving force of low viscosity gasoline engine oil research and development considered by the original equipment manufacturers (OEMs) and lubricant companies. The development of low viscosity gasoline engine oils should not only focus on fuel economy improvement, but also on the low speed pre-ignition (LSPI) prevention property. In previous LSPI prevention literatures, the necessity of applying Ca/Mg-based detergents system in the engine oil formulations was proposed. In this paper, we adopted a specific Group III base oil containing Ca-salicylate detergent, borated dispersant, Mo-DTC in the formulation and investigated the various effects of Mg-salicylate and Mg-sulfonate on the performance of engine oil. It was found that Mg-sulfonate showed a significant detrimental impact on silicone rubber compatibility while the influence from Mg-salicylate remains acceptable.

The increased use of recycled resins can create a dilemma for automotive designers. On the one hand, there is a growing initiative to increase recycled materials content on vehicles, globally. On the other hand, traditional methods of recycling polymeric materials -both thermoplastics and thermosets - can lead to degradation of engineering, mechanical, processing, and / or aesthetic properties of the resin. In an era where quality rules, this situation forces designers to accept a much lower percentage of recyclate than they might otherwise wish to use or risk unacceptable property loss in molded parts - something no automaker can “afford ” for long. Hence, a valuable feedstream of materials (polymers) often ends up destined for a landfill once many consumer products are broken down and more easily reusable or recyclable materials are salvaged. As a case in point, each passenger car built globally contains an average of 15 - 20 kg of nylon polymers.

Up to now, various compressor models for automotive air conditioners have been manufactured to answer the needs of car manufacturers for fuel economy and quietness. The 10PC20 compressor, developed for automotive air conditioners, is the world's first swash plate type compressor having a continuously variable displacement mechanism. The 10PC20 is aimed at realizing a large displacement compressor with a continuously variable displacement mechanism, which has not been achieved until today. To achieve this goal, the 10PC20 design is based on the swash plate type compressor, consisting of double-headed pistons, which is adaptable to a large displacement and has excellent rotating balance and durability. The 10PC20 changes its displacement continuously by changing the inclination of the swash plate (swash plate angle) continuously. (See photo. 1 and 2) The 10PC20 adopts two variable displacement principles.

Carbon fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This paper describes eleven design rules originating from different guidelines that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components and access for non-destructive testing (NDT). To verify the technical content and ensure practicability, the rules were developed by, inter alia, studying literature and performing case studies at SAAB Aerostructures.

The trend towards battery voltage vacuum fluorescent displays continues the technological advances in design and construction of VFD's, as they are applied to the automobile environment. With the ever increasing use of electronic displays for electronically tuned radios (ETR's), compact disc (CD) players, and other entertainment systems, advances in battery voltage displays and their associated drive circuitry have become a necessity. With the inherent advantages of low voltage operation and high information density, VFD's will continue to dominate the automobile audio markets. This paper will discuss battery voltage displays, the basic circuitry necessary to operate a vacuum fluorescent display, and comment on the “off the shelf” controller and driver circuitry available.

Two-phase capillary loops are being extensively studied as heat collection and rejection systems for space applications as they appear to satisfy several requirements like low weight, low volume, temperature control under variable heat loads and/or heat sink, operation under on ground and micro gravity conditions, simplicity of mounting and heat transfer through tortuous paths. In 1998–2000 Alenia defined and Lavochkin Association developed the Deployable Radiator on the base of honeycomb panels, axial grooved heat pipes and Loop Heat Pipe. It was designed for on-ground testing.

Flexibility, oil resistance, and the need for heat resistance to 150°C-plus temperatures have traditionally limited automotive design engineers to two options - thermoset rubber or heat-shielding conventional thermoplastic elastomers (TPE). Both of these options present limitations in part design, the ability to consolidate the number of components in a part of assembly, and on total cost. This paper presents a class of high-performance, flexible thermoplastic elastomers based on dynamically vulcanized polyacrylate (ACM) elastomer dispersed in a continuous matrix of polyamide (PA) thermoplastic. These materials are capable of sustained heat resistance to 150°C and short-term heat resistance to 175°C, without requiring heat shielding. Recent advancements in blow molding and functional testing of the PA//ACM TPEs for automotive air management (ducts) and underhood sealing applications will be shown.

THIS paper deals with the road-test portion of the extensive efforts made during 1937 by the Cooperative Fuel Research Committee to get as precise a correlation as possible between the laboratory knock ratings of automobile fuels and their corresponding ratings in cars on the road. It is anticipated that the comprehensive results of car tests reported here, taken together with the results of the laboratory rating program reported in the companion paper, will serve as the basis of the continuing studies aimed at developing the best possible correlation between road and laboratory knock ratings. Work similar to that reported here has been conducted concurrently in England by the Institution of Petroleum Technologists, using British cars and fuels. An exchange of information between the British and American groups working on this problem is being made.

THE 1940 CFR Road Tests have developed new information that can be used for the development of fuels and engines. Application of the principles worked out in these tests is expected to result in a more efficient utilization of fuel antiknock properties and more effective engine design and adjustment to meet the requisites of current motor fuels. These tests indicate that the ASTM octane number alone, or even a road octane number as determined by methods heretofore widely used, does not give sufficient information for present needs relative to fuel behavior in service. Neither do test methods previously used provide sufficient information concerning the fuel requirements and knocking characteristics of engines. The new methods of approach which have been developed furnish needed information relative to the fuel and engine relationship that heretofore has been obscure, and indicate paths for future developments.

The cooperative road tests carried out during 1941 have added considerable information and experience to that already existing on the subject of road detonation testing. Extensive data were obtained on the fuel requirements of the 1940 and 1941 models of the three most popular cars. Corresponding data were obtained on the knocking characteristics of current gasolines representing the bulk of the sales volume in various parts of the United States. On account of large variations in octane-number requirement among different cars of the same make - due to differences in ignition timing, combustion-chamber deposit, and other causes - and on account of variations in commercial gasolines, it has been necessary to use statistical methods of analysis in the appraisal of fuel and engine relationships. These methods of analysis have been applied in a number of ways, and have proved very useful.

Background of the Pure Oil performance trials on six classes of automobiles is presented and the evolution of test requirements described. Three tests are run: the economy test to establish how far a vehicle can go over a prescribed course on one gallon of gasoline; the acceleration test which determines acceleration time from 25 to 70 mph in seconds; and the braking test where stopping distance in feet is measured for a stop from 60 mph. Each test is described from the point of view of rules, recording instruments, and penalties for infractions of rules. Test results are presented.

The recent introduction of lower compression ratio engines and the concurrent marketing of unleaded and low-lead content gasolines of generally lower octane number made it appropriate to investigate the interrelationships of engine performance and gasoline octane quality using the “new” engines and fuels. Programs were carried out to compare fuel economy and acceleration performance of eight matched pairs of 1970 and 1971 automobiles. In addition, octane requirements were obtained on 43 1971 cars with 3,000-12,000 deposit miles. A total of 146 unleaded, low-lead, and leaded regular gasolines obtained at service stations throughout the country were analyzed, and the road octane performance of these gasolines was determined using 1970 and 1971 cars designed for regular gasoline.

Weight and performance characteristics of the 1979 Pontiac Firebird soft bumper system are compared to those for a typical new (1979) metal/hydraulic design to evaluate the effects of the new standard. This study demonstrates the changing competitive environment in the automotive bumper market due to the introduction of the Part 581 Standard. The deep soft bumper concept is also discussed including its potential for achieving weight reductions in future elastomeric bumper systems.

A gasoline Road Octane study was conducted by the Coordinating Research Council (CRC) to evaluate the effects of heavy aromatics (C9 and heavier) and ethanol content on Road Octane performance independent of Research Octane Number (RON) and Motor Octane Number (MON). Maximum-throttle and part-throttle Road ON’s were found to be well predicted by equations containing only RON and MON terms. Heavier aromatics were found to have a small adverse effect on both maximum-throttle and part-throttle Road ON independent of its direct effects on RON and MON. The all-car data did not show a significant ethanol-content effect, but eight of the thirty-seven cars did show significant effects for ethanol content.

As part of the 1997 Propane Vehicle Challenge, a team of twelve UTEP students converted a 1996 Dodge Grand Caravan with a 3.3 L V6 engine to dedicated Liquefied Petroleum Gas (LPG) operation according to the 1997 Propane Vehicle Challenge (PVC) competition rules (16). The 1997 UTEP team developed an LPG liquid phase port fuel injection (LPP-FI) system for the minivan. The UTEP design strategy combines simplicity and sound engineering practices with the effective use of heat resistant materials to maintain the LPG in the liquid phase at temperatures encountered in the fuel delivery system. The team identified two options for fuel storage with in-tank fuel pumps. The competition vehicle incorporates a five-manifold eight inch diameter Sleegers Engineering LPG tank fitted with a Walbro LPTS in-tank pump system, providing a calculated range of 310 city miles and 438 highway miles.

Using a holistic 1D engine simulation approach for the modelling of full-transient engine operation, allows analyzing future engine concepts, including its exhaust gas aftertreatment technology, early in the development process. Thus, this approach enables the investigation of both important fields - the thermodynamic engine process and the aftertreatment system, together with their interaction in a single simulation environment. Regarding the aftertreatment system, the kinetic reaction behavior of state-of-the-art and advanced components, such as Diesel Oxidation Catalysts (DOC) or Selective Catalytic Reduction Soot Filters (SCRF), is being modelled. Furthermore, the authors present the use of the 1D engine and exhaust gas aftertreatment model on use cases of variable valve train (VVT) applications on passenger car (PC) diesel engines.