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Two or more aftertreatment systems will be required for diesel vehicles to reduce PM and NOx, simultaneously and achieve the same levels of exhaust emissions as gasoline vehicles. Thus, aftertreatment devices such as the DPF and DeNOx catalyst need to be compact and less restrictive to exhaust gas flow. An IP Filter for removing particulate in exhaust gas has been developed to reduce both unit size and pressure drop and structured to integrate the DOC and DPF functions into one unit. A conventional wall-flow DPF has a cellular structure with either individual open-end or closed-end channels on both the inlet and outlet sides. The IP Filter has no plugs on the front end but has plugs at the interface of the DOC and DPF parts (internal plugs) in addition to the plugs at the rear end. Several test IP Filters that were made of highly porous cordierite material were prepared for testing to evaluate their performance characteristics.

It is said that rollforming technology is one of the most effective uses of Ultra High Strength Steel (UHSS). The method by which a new vehicle side structure concept can satisfy IIHS (Insurance Institute for Highway Safety) side impact test criteria was studied by utilizing IIHS’s technologies. First of all, the best structural ideas for each part (e.g. B-pillar, side sill, roof cross member and floor cross member, etc.) based on the closed sections utilizing the rollforming technology and UHSS were studied using the crash CAE of each part. The best solutions for each part were assembled on the vehicle side structure CAE model, and the crash performance of the IIHS side impact test was confirmed using the module part of the crash CAE model. The great weight saving possibility of the new vehicle side structure concept was proven by comparing it to the conventional structure concept based on the stamped parts.

Tubular hydroforming is being used extensively for manufacturing various automotive structural parts due to its weight reduction and cost saving potentials. The use of a thin wall advanced high strength steel (AHSS) tube offers great potential to further expand hydroforming applications to upper body components. In this study, numerical and experimental investigations are conducted on a free expansion hydroforming case using various AHSS thin wall tubes. The results are also compared with tubes made from conventional steels and different tubing processes. The appropriate use of the forming limit in hydroforming is also discussed. In numerical study, a new simulation method is developed and validated to handle tube material properties input. Good correlations to the experimental data have been obtained. The new method only requires the flat sheet stress–strain curves as the basic material property. Tube and weld properties are modeled as a pre-strained tubular blank.

Advanced high strength steels (AHSS), such as dual phase (DP) and transformation induced plasticity (TRIP) steels, have been increasingly used in automotive industry. One of the major advantages of AHSS is the excellent crash energy absorption capability. In this study, crash performances were evaluated for four AHSS including DP980, DP780, TRIP780 (780T), and TRIP590 (590T). Axial crush and bending crush tests were performed to evaluate the material crush performance. High strain rate tension test results for those materials were also presented. FEA analyses with parameter sensitivity studies were conducted including strain rate sensitivity effect, part geometry effects, welding models and forming effects. Good correlations between simulation and experimental data were achieved.

This newly developed 1.6L engine achieves, in comparison with a conventional engine, an 7% reduction in fuel consumption in stoichiometric operation, by improving combustion through modification of the shape of the intake port and combustion chambers, and by adopting friction-reducing technologies. Also, the adoption of a high-density, thin-walled catalyst (900 cells, 2.5 mil unit) and early activation of the catalyst through catalyst quick warm-up control, makes it possible to comply with Euro4 gas emission standards by reducing emissions in cold start and immediately thereafter.

A four-track steering vehicle(4TS) is a new concept of off-road vehicles the tires of which have been replaced with tracks to improve mobility on a soft terrain. In this paper, a theoretical model to predict the steerability and mobility of the vehicles has been developed and the validity of the theoretical model is verified by the scale model and real vehicle tests. From the results of numerical analysis and experiments, it is found that the required driving force and track slip sinkage for steering are small noticeably as compared with those existing tracked vehicles, and so the mobility of a four tracked steering vehicle will be improved on soft terrain, especially, on snow surface.

A side impact study using eight impact configurations was conducted in conformity with a test method proposed by the U.S. (NHTSA) and another method currently under study in Europe (EEVC). On the basis of the data obtained, parameters possibly influencing the injury value of a dummy were examined. Also, the possibility of developing an alternative test in which the MDB (moving deformable barrier) is replaced by an MRB (moving rigid barrier) was considered. The results are as follows: (1) Comparison of NHTSA and EEVC Test Methods 1) Difference Between NHTSA and EEVC Methods The U.S. NHTSA and European EEVC test methods caused widely different dummy injury values due to the different test conditions of the MDB, the crabbed angle, and the dummy.