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Vehicles are required durability in various environments all over the world. Especially water resistance on flooded roads is one of the important issues. To solve this kind of problem, a CFD technology was established in order to predict the water resistance performance of the vehicle at the early development stage. By comparison with vehicle tests on flooded roads, it is clarified the following key factors are required for accurate prediction; the vehicle velocity change, the vehicle height change and the air intake flow rate. Moreover, these three key factors should be appropriately determined from vehicle and engine specification to predict water intrusion for flooded roads at the early stage of development. In this paper, a methodology which determines appropriate analysis conditions mentioned above for flooding simulation from vehicle and engine specification is described. The methodology enables us to determine whether the vehicle provides sufficient waterproofness.

Into the early-part of the next century, automotive emission standards are becoming stricter around the world. The electrically-heated catalyst (EHC) is well known as an effective technology for the reduction of cold-start hydrocarbon emissions without a significant increase in back pressure. Our extruded, alternator powered EHC (APEHC) manufactured with a unique canning method and equipped with a reliable, water proof electrode has demonstrated excellent durability and reliability, as stated in our previous SAE paper (#960340). The APEHC system discussed in this paper has achieved the Ultra-Low-Emission Vehicle (ULEV) standards, after 100,000 miles of fleet testing, without any failure. This is the final milestone in addressing the EHC as a realistic-production technology for ULEV. With the ability to meet ULEV/Stage III emission targets without a significant increase in back pressure, the EHC will be applied to an especially high performance vehicle with a large displacement engine.

The use of waste heat for automobile engine that applied Rankine cycle from the viewpoint of exergy (available energy) was researched. In order to recover heat to high quality energy, a heat-management engine whose exhaust port was replaced with an innovative evaporation device was developed. With this engine, high temperature and high pressure steam (400 degree C, 8MPa) could be generated from a large amount of the exhaust loss. In addition, high temperature water (189 degree C) was obtained from cooling loss. Consequently, the system that recovered more exergy from waste heat was established. To verify the system, the Rankine cycle system was installed in a hybrid vehicle and the automatic control system to change steam temperature and pressure according to the load variation was constructed. As the result of vehicle testing, thermal efficiency was increased from 28.9% to 32.7% (by 13.2% increase) at 100km/h constant vehicle speed.

High-tensile steel plates and lightweight aluminum are being employed as materials in order to achieve weight savings in automotive subframe. Closed-section structures are also in general use today in order to efficiently increase parts stiffness in comparison to open sections. Aluminum hollow-cast subframe have also been brought into practical use. Hollow-cast subframe are manufactured using sand cores in gravity die casting (GDC) or low-pressure die casting (LPDC) processes. Using these manufacturing methods, it is difficult to reduce product thickness, and the limitations of the methods therefore make the achievement of weight reductions a challenge. The research discussed in this paper developed a lightweight, hollow subframe technology employing high-pressure die casting (HPDC), a method well-suited to reducing wall thickness, as the manufacturing method. Hollow-casting using HPDC was developed as a method of forming water jackets for water-cooled automotive engines.

In order to reduce emissions and enhance energy security, renewable power sources are being introduced proactively. As the fraction of these sources on a power grid grows, it will become more difficult to maintain balance between renewable power supply and coincident demand, because renewable power generation changes frequently and significantly, depending on weather conditions. As a means of resolving this imbalance between supply and demand, vehicle-to-grid (V2G) technology is being discussed, because it enables vehicles to contribute to stabilizing the power grid by utilizing on-board batteries as a distributed energy resource as well as an energy storage for propulsion. The authors have built a plug-in vehicle with a capability of backfeeding to the power grid, by integrating a bi-directional on-board AC/DC and DC/AC converter (on-board charger) and a digital communication device into the vehicle. The vehicle is interconnected to a power regulation market in the United States.

Water management is one of the key factors to ensure high performance, cold start and durability of polymer electrolyte fuel cells (PEFCs), and it is important to understand the behavior of liquid water in PEFCs. X-ray computed tomography (X-ray CT) imaging and the two-phase lattice Boltzmann method (two-phase LBM) are applied to analyze the mechanism of water transport in the gas diffusion layers (GDLs) and the gas channels in generating PEFCs. The results of the two-phase LBM are compared with those of X-ray CT imaging, and are found to agree qualitatively in that water is discharged along the hydrophilic channel wall and accumulated in the GDL, especially under the rib. The effects of the wettability of the GDLs, and of the gas channels, the diameter of the carbon fibers, and the porosity of the GDLs on water discharge from the GDLs and gas channels are also investigated.

This paper introduces the newly developed super sports car engine mounted in the new model NSX. A super sports car engine was newly developed to satisfy the high power performance required by the body package. Higher power and compactness were simultaneously achieved by selecting an engine displacement of 3.5 L and by using a V6 layout and a turbocharger. This enabled to mount a power train that combines a hybrid motor with a newly developed transmission in the rear of the body. The lubrication system uses a dry sump system capable of maintaining reliable lubrication in all possible super sports car driving scenarios. The combustion system uses high tumble-flow ports, a direct injection and a port injection system that increase power performance and thermal efficiency, emission reduction. To support the increased heat load due to higher power, a 3-piece water jacket is used around the combustion chamber and the exhaust ports.

In conventional CAE (Computer Aided Engineering), methods using grids, such as the finite element method and the finite volume method, are commonly used. However grids are sometimes problematic in cases of dynamic free surface flows, with large deformation or breaking. In this study, a novel three-dimensional fluid, structural analysis simulation program to reproduce the dynamic behavior of water or soil in the mechanical parts of a product equipped with a small engine was developed. This simulation program expresses water or soil as particles within boundaries having complicated configuration. These particles are then replaced with a polygon model to lower calculation load and to improve accuracy of configuration reproducibility. In the structural analysis, a breaking condition which considers the effect of soil compaction was designed to reproduce the break up of material with special characteristics such as soil.