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Abstract The paper presents a complete description of the design and manufacturing of a Carbon Fiber/epoxy mold with an embedded Carbon Fiber resistor heater, and the mold performances in terms of its surface temperature distribution and thermal deformations resulting from the heating. The mold was designed for manufacturing aileron skins from Vacuum Bag Only prepreg cured at 135°C. The glass transition temperature of the used resin-hardener system was about 175°C. To ensure homogenous temperature of the mold working surface in the course of curing, the Carbon Fiber heater was embedded in a layer of a highly heat-conductive cristobalite/epoxy composite, forming the core of the mold shell. Because the cristobalite/epoxy composite displayed much higher thermal expansion than CF/epoxy did, thermal stresses could arise due to this discrepancy in the course of heating.

To reduce heat transfer between hot gas and cavity wall, thin Zirconia (ZrO2) layer (0.5mm) on the cavity surface of a forged steel piston was firstly formed by thermal spray coating aiming higher surface temperature swing precisely synchronized with flame temperature near the wall resulting in the reduction of temperature difference. However, no apparent difference in the heat loss was analyzed. To find out the reason why the heat loss was not so improved, direct observation of flame impingement to the cavity wall was carried out with the top view visualization technique, for which one of the exhaust valves was modified to a sapphire window. Local flame behavior very close to the wall was compared by macrophotography. Numerical analysis by utilizing a three-dimensional simulation was also carried out to investigate the effect of several parameters on the heat transfer coefficient.

Abstract Insulating combustion chamber surfaces with thermal barrier coatings (TBCs) provides thermal efficiency improvement when done appropriately. This article reports on insulation heat transfer, engine performance characteristics, and damage modelling of “temperature swing” TBCs. “Temperature swing” insulation refers to the insulation material applied on surfaces of combustion chamber walls that enables selective manipulation of its surface temperature profile over the four strokes of an engine cycle. A combined GT Suite-ANSYS Fluent simulation methodology is developed to investigate the impact of thermal properties and insulation thickness for a variety of TBC materials for its “temperature swing” characteristics. This one-dimensional transient heat conduction analyses and engine cycle simulations are performed using scaled-down thermal properties of yttria-stabilized zirconia.

This recommended practice applies to off-road, self-propelled work machines defined in SAE J1116 JUN81.

This SAE Recommended Practice applies to off-road, self-propelled work machines defined in SAE J1116 JUN81.

These remanufacturing procedures are recommended minimum guidelines (with the understanding that more stringent procedures are acceptable) for use by remanufacturers of heavy-duty starters to promote consistent reliability, durability, and safety of remanufactured starters. Installation of remanufactured or rebuilt products is often an economical way to repair an application even though the products may not be identical to original equipment parts. Before processing any part, a remanufacturer should determine if the original design and present condition of the core are suitable for remanufacturing so as to provide durable operation of the part as well as acceptable performance when installed on the application. The remanufacturer should also consider the safety aspects of the product and any recommendations of the original manufacturers related to remanufacturing or rebuilding their product.

These remanufacturing procedures are recommended minimum guidelines (with the understanding that more stringent procedures are acceptable) for use by remanufacturers of heavy-duty starters to promote consistent reliability, durability, and safety of remanufactured starters. Installation of remanufactured or rebuilt products is often an economical way to repair an application even though the products may not be identical to original equipment parts. Before processing any part, a remanufacturer should determine if the original design and present condition of the core are suitable for remanufacturing so as to provide durable operation of the part as well as acceptable performance when installed on the application. The remanufacturer should also consider the safety aspects of the product and any recommendations of the original manufacturers related to remanufacturing or rebuilding their product.

This SAE Recommended Practice covers the details, dimensions, and design of the parts of both plug and receptacle which must mate properly to permit interchangeable use of different makes of connectors. It provides the auxiliary starting circuit of the machine with a universal connecting device, fool-proof polarity, standard circuit coding, and protection for the wiring and equipment from electrical shorts.

This SAE Standard defines the requirements for a plug and receptacle used in an auxiliary starting system. The connector facilitates the application of supplemental electrical power for starting or charging a machine from another machine or suitable external source. This system provides: proper polarity during connector mating, secure electrical connections, and standard circuit color coding.

This SAE Standard defines the requirements for a plug and receptacle used in an auxiliary starting system. The connector facilitates the application of supplemental electrical power for starting or charging a machine from another machine or suitable external source. This system provides: proper polarity during connector mating, secure electrical connections, and standard circuit color coding.

This SAE Recommended Practice covers the details, dimensions, and design of the parts of both plug and receptacle which must mate properly to permit interchangeable use of different makes of connectors. It provides the auxiliary starting circuit of the machine with a universal connecting device, fool-proof polarity, standard circuit coding, and protection for the wiring and equipment from electrical shorts.

This SAE Standard defines the requirements for a plug and receptacle used in an auxiliary starting system. The connector facilitates the application of supplemental electrical power for starting or charging a machine from another machine or suitable external source. This system provides: proper polarity during connector mating, secure electrical connections, and standard circuit color coding.

The first single-piece, injection-molded, thermoplastic, front bumper for a light truck provides improved performance and reduced cost for the 1997 MY Explorer® Ltd. and 1988 MY Mountaineer® truck from Ford Motor Company. Additionally, the system provides improved impact performance, including the ability to pass 5.6 km/hr barrier impact tests without damage. Further, the advanced, 1-piece design integrates fascia attachments, reducing assembly time, and weighs 8.76 kg/bumper less than a baseline steel design. The complete system provides a cost savings vs. extruded aluminum and is competitive with steel bumpers.

The 1997 F-Series and Expedition Instrument Panel programs were initially launched with steering column and glove compartment knee bolsters constructed of compression molded, glass filled polypropylene. First run capability of the material at production speeds was only 65 percent due primarily to dimensional stability (warp), paint adhesion, and excessive rework issues. A Ford APO (now Visteon) / Dow Automotive† team was formed to seek a replacement material / design for the glass filled polypropylene material which would solve the problems. The new material system had to meet or exceed current FMVSS 208 crash performance standards, provide improved quality and reduce variable and scrap costs all with a minimum tooling investment. Using Dow PULSE™ PC/ABS resin, the team designed / implemented a new knee bolster system in 12 months.

How shall we improve the quality and reliability of the software we produce? We believe that the critical factor is an understanding how software is constructed, and why it is constructed in that way. Once something is understood, we can begin to build better tools to support and mold the process. This paper outlines a view of how the software process proceeds, why it proceeds that way, and how we can use this perspective to build better tools.

In the past there has been a concentration on performing LCAs of car components. Based on the increasing experience and know-how gained in the past by performing LCAs of car components truck designers get the chance to make a statement about the ecological impact of each alternative. The most significant difference between LCAs of car and truck components is the use phase. This paper describes a Life-Cycle-Assessment (LCA) of different air deflection systems made of composite materials. The actually used system is produced by Resin Transfer Molding (RTM) while a possible alternative could be made out of Sheet Molding Compound (SMC). The calculations have shown that there exists a potential to improve the ecological profiles of composite components by replacing glass fibers with natural fibers.

Western Canada has large acreage of oilseed flax, but unfortunately a small percentage of total crop residue (flax straw) produced annually is being commercially used. Therefore, farmers are still burning the flax straw. Flax fiber and straw has highest strength amongst the different natural fibers, therefore, the prospect of using them as biorenewable reinforcement in recycled/ virgin polymer matrices has gained attention in recent years. Flax strawboard has a potential to replace the currently used wood and other crop like wheat/barley straw boards for different industrial application. In this research Oilseed flax straw reinforced composite boards were developed using flax shives with biopolymer binder made out of recycled/ pure thermo plastic and flax fiber. Some advantages of such materials are high strength, low density, good insulation capacity against heat and moisture transfer, and biodegradability.

Objective of this study was to develop basic techniques in order to apply aluminum sandwich sheets for an automotive hood part. The aluminum sandwich sheet is the material fabricated by adhering two aluminum skins to one polypropylene core. When it has the same bending stiffness as a steel sheet, it is 65% lighter than the steel sheet and 30% lighter than an aluminum alloy sheet. Therefore, it is notified exclusively as good substitutive materials for a steel body to improve the fuel efficiency. Through aluminum sandwich sheet, however, it has relatively lower formability than that of the steel sheet for automotive application. In this study, we fabricated a prototype of the automotive hood panel to develop application techniques of the aluminum sandwich sheet.

A vehicle cooling system development and optimization success is strongly dependent on the prevention of recirculation zones and other areas of heat transfer and air flow concerns generated by underhood components. Traditionally, noise insulation package is defined without considering its impact on the thermal environment surrounding it. However, the airflow restriction created by the noise shields surfaces may become a huge air flow issue. This situation is usually verified on trucks designed for tropical markets and submitted to severe environments. This paper presents a development strategy coupling cooling and underhood air flow management package specification with pass-by-noise insulators design. The interaction between cooling and pass-by-noise developments must avoid the necessity of a later redesign phase. A CFD software, lab sound intensity noise source ranking tests as well as vehicle cooling testing are suggested as development tools.

Multiwall carbon nanotubes are an extremely small conductive additive for plastics. They are about 10 nanometers in diameter and 10 or more microns long. Their high aspect ratio (1000:1) allows equivalent conductivity at lower loading compared to carbon black, chopped carbon fiber or stainless steel fiber. The advantage of a lower additive loading is a greater retention of the inherent ductility of the resin. Additionally, the small size of the nanotubes, coupled with the low loading, results in a much smoother molded part surfaces than when larger additives are used. In this paper, we will present comparative data of physical properties, surface smoothness, moldability and electrical conductivity for compounds containing different conductive additives. Finally, existing and evolving commercial applications will be reviewed.