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In this research, a material model was developed that has orthotropic properties with respect to in-plane damage to support finite element strength analysis of components manufactured from a randomly oriented long-fiber thermoplastic composite. This is a composite material with randomly oriented bundles of carbon fibers that are approximately one inch in length. A macroscopic characteristic of the material is isotropic in in-plane terms, but there are differences in the tension and compression damage properties. In consideration of these characteristics, a material model was developed in which the damage evolution rate is correlated with thermodynamic force and stress triaxiality. In-plane damage was assumed to be isotropic with respect to the elements. In order to validate this material model, the results from simulation and three-point bending tests of closed-hat-section beams were compared and found to present a close correlation.

This study developed a material model with a damage function that supports finite element analyses in crash strength analyses of beams manufactured using randomly-oriented long fiber thermoplastics composites. These materials are composites with randomly-oriented carbon tow having a fiber length of approximately one inch, and are isotropic in-plane from a macro perspective, but exhibit different damage properties for tension and compression. In the out-of-plane direction, the influence of the resin matrix properties increases, and the materials properties are similar to those of laminate materials. This means they are anisotropic materials with physical properties that differ from those in the in-plane direction. In order to verify the influence of these characteristics, the damage process was observed by three-point bending of a flat plate, which is a mixed mode that includes tension, compression, and out-of-plane shear.

A Roadside Air Quality Simulation Model (RsAQSM) was developed in Phase II of the Japan Clean Air Program (JCAP II) for use in analyzing and studying strategies to address roadside air quality problems along main roads in urban areas. RsAQSM consists of (1) a micro-scale traffic model, (2) a transient emission estimation model, and a (3) wind and advection/diffusion model. Paramics was used to simulate the transient behavior of vehicles on roads in sub-model (1). Transient vehicular emissions were estimated using a newly developed transient emission database and methodology in sub-model (2). In sub-model (3), Star-CD was used to simulate wind flow and advection/diffusion of emissions, using a calculation mesh representing the detailed shapes of structures such as buildings or elevated roads and micro-scale topography along the roads. Each sub-model was validated in a real-world situation.

Intermittent Dual-fluid Exhaust Burner (IDEB) has been developed to reduce emissions from methanol fueled vehicles during the warm-up period after a cold start. The IDEB does not need any special fuel injector or blower, and has been built mainly through software modification of an ECU. An FTP mode test while operating an IDEB confirmed that the catalyst temperature was rapidly increased to significantly reduce the emissions to meet a level of ULEV standards.