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The spray characteristics and inside flow of a marine diesel injector were investigated both experimentally and numerically. From the experiments, we observed that the penetration of the sprays in the early injection stage gradually increases. This phenomenon differs significantly from that of the small automobile diesel injector, in which penetration increases linearly with time. Using the momentum method to obtain injection rate measurements, we observed an injection rate spike at each injection event just after the injection began. The observed spray results show that the small portion of fuel remaining inside the nozzle from the previous injection event is ejected first, and then the main volume of fuel is ejected. Both fuels accumulate as spray droplets and gradually accelerate after the early injection stage. Numerical simulations of the injector's inside flow show that the fuel injection rate becomes saturated in needle lifts larger than 0.3 mm.

Customer's expectations are increasing in the competitive automotive market. In an effort to enhance marketability, interior and exterior trim parts that are comprised of plastic, paints, and films are being assessed for scratch and scuff durability. There are many different methods used inside and outside the automotive industry to determine the performance of these materials. However, the majority of these methods do not correlate the performance of the material to the customer's expectations. This paper reviews existing scratch/scuff methods and advancements in scratch/scuff performance test methodology from analyzing driver and passenger zones, customer expectations, and part design.

Understanding of the oil film formation mechanism around a piston skirt is very important to reduce the friction loss at piston skirt. We have investigated lubricant oil film behavior around piston skirt which is affected by piston slap under motoring condition. In this study, a cylinder liner of a commercial engine is displaced with a quartz cylinder. Photographic observations of oil film behavior between the cylinder liner and the piston skirt were performed with two kinds of methods; direct monochromatic photography and LIF (Laser Induced Fluorescence) image using a high speed camera. The oil film distributions were determined from oil boundary observed by the direct photography, and oil film thickness was estimated from the LIF intensity. Differences of the oil film distributions and the oil film thickness depending on piston shapes were investigated for four types of pistons.

Due to the progression of environmental regulations, as they pertain to interior air quality, automakers and their respective supply-chain are considering current and future volatile organic compound (VOC) requirements of the vehicle cabin. Currently, initiative is being taken in order to attempt to reduce the VOC levels associated with these and other products sold around the world. This paper will include an overview of existing regulations throughout the world and advancement in the reduction of VOC levels, including the methodology used to measure VOC content and specific technologies used to reduce VOC levels.

Mono-materials are utilized in soft pads for automotive interior components to ease recycling efforts. Olefin is an example of a mono-material, and olefin instrument panels (I/P) are produced using a vacuum forming method. To simplify the production process for these parts, adhesive spray coating on the surface of the plastic foundation has been replaced by pre-coating on the reverse surface of the laminated skin, enabling the reduction of both adhesive spraying and drying procedures in the forming process. Development of an adhesive with excellent high temperature adhesion performance on olefin has eliminated the necessity for pretreatment of the olefin foundation and the skin (primer treatment and flame treatment). This has enabled a significant reduction in the forming procedures and has rationalized the process.

This paper describes the investigation into the contact pressure and incidental deformation on the contact surface of the piston skirt which comes in contact with the cylinder bore in operation. Focused on the single piston static tests in the first place, relationship between the contact pressure on said skirt and the strains developed inside the skirt, and the relationship between the deformation of skirt face and the strains inside the skirt were studied. Then, the dynamic contact pressure onto the skirt in operation and the amount of deformation were calculated based on the relationships mentioned above using the factor of dynamic strains measured on an engine in operation. The deformation of skirt calculated using said dynamic strains was verified by the direct measurement of the skirt deformation. It was demonstrated that the thrust side of a piston skirt was largely deformed due to enlarged contact pressure caused by the piston slap subsequent to firing top dead center.

Two-part water-based adhesive for instrument crash pad vacuum forming was developed. It uses a self-emulsification type of urethane emulsion which does not contain any organic solvents as its main ingredient. And, a number of additives which are effective in improving adhesion to both an injection molded acrylonitrile-butadiene-styrene (ABS) foundation and the PVC/PPF skin have been blended in this urethane emulsion. So, this water-based adhesive has excellent initial adhesive properties, reliable durability and mass productivity which are all required of adhesives for instrument crash pad applications.