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Around the world, the major automakers are developing their strategies for conductive and wireless charging technologies, with concerted efforts to establish technical standards on wireless electric vehicle charging, mainly focused on the safety considerations and inter-operability. Wireless Charging Technology and the Future of Electric Transportation covers the current status of wireless power transfer (WPT) technology and its potential applications to the future road and rail transportation systems. Focusing on the applications of WPT technology to electric vehicle charging and the future green transportation field, Wireless Charging Technology and the Future of Electric Transportation was written collaboratively by nine experts in the field, led by Dr. In-Soo Suh, a professor and researcher from the Korean Advanced Institute of Technology (KAIST).

Optimizing base engine design in view of performance, emission requirement, durability, and lighter weight has been a challenging work in automotive industry for a last couple of decades. While those functional requirements are designed and developed to be met, NVH requirement has been one of difficult objectives to be optimized in the design and development process, not only because of technical difficulties, but of the lesser degree of settlement of development process in a vehicle program. The combustion characteristic of an engine plays an important role in the performance, emission, and NVH development. In this paper, the engine radiation sound and mounting vibration have been measured simultaneously with the combustion pressure from each cylinder of a V8 engine while varying the engine speed under wide open throttle condition and spark timing.

The dynamic behavior of an OHC valve train system of a spark ignition engine is investigated to characterize the source and transmission of the valve train (VT) vibration and noise and to improve the VT design for better sound quality. The spectral properties of vibration caused by highly transient dynamics of VT system are characterized for the high frequency ranges over 3 kHz, although the overall sound pressure level due to the VT is negligible [1, 2]. For the analysis of valve train a lumped parameter model with 4 d.o.f.'s is developed and validated with the experimental results from a test rig. Experiments are performed on the test rig to measure the valve acceleration, the surface vibration of cylinder head during the operation, and the transfer functions. Also a measurement of cylinder head vibration in a real vehicle has been performed to correlate with the rig test results.

Many kinds of additives such as viscosity index (VI) improvers, anti-wear additives, rust-corrosion inhibitors, antioxides, etc. are added in the lubricant for modern engines. In particular, VI improvers of high molecular weight polymer content are added to base oils to give multigrade oil characteristics against temperature-viscosity sensitivity. However, the incorporation of polymeric additives produces significant decrease of thickening effect by the polymeric additives even at normal operating speed (106s-1) of engine components as well as boundary film formation by the sticking layer of polymeric additives on the solid surfaces. The shear thinning effect of polymeric additives causes serious wear due to reduced film thickness while it may reduces friction forces and the sticky-absorbed polymeric layer protects the surfaces. Abnormally thin film thickness (0.01∼0.1μm) can frequently happen in cam and follower contacts under high fluctuating concentrated loading condition.

Local transient heat-flux measurements and heat-release analyses were employed to investigate the effects of introducing swirl or tumble fluid motion during the intake stroke on the combustion and heat-transfer characteristics of a single-cylinder spark-ignition engine. In general, swirl or tumble motion decreased the period of flame development and increased the peak rate of heat release, but, surprisingly, it increased the period of combustion. The latter increase was the result of comparatively low rates of fuel burning during the last stages of combustion. Swirl or tumble motion also significantly increased the local heat flux on the cylinder head. The highest peak heat flux was obtained for tumble motion. The observed increase in heat flux is attributed to the resultant increase in the mean velocity and in the turbulent intensity of the gases in the combustion chamber, which, in turn, augment the rate of heat release and the effective convective heat-transfer coefficient.