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Requirements of side curtain airbag have continued to increase. The revised SINCAP, FMVSS-226 ejection mitigation and small overlap of IIHS had added these requirements. To meet all the requirements, high inflator energy and complex cushion shape became necessary. Such situations increased possibility of cushion failure while deploying. Unfortunately, all the design verification tests are usually completed in a relatively latter stage of development and repetitive testing is needed to consider large dispersion of failure probability distribution. Therefore, verification and design improvement by numerical simulation in an early stage are desirable. A simulation method which can verify CAB deployment was developed in this study. The developed method has three distinct features. Firstly, nonlinear fabric materials and membrane finite elements are used to consider fracture of cushion fabric. Secondly, a pre-simulation procedure had been established.

In current inflatable curtain airbag development process, the curtain airbag performance is developed sequentially for the airbag coverage, FMVSS 226, FMVSS 214 and NCAP. Because the FMVSS 226 for the ejection mitigation and the NCAP side impact test require the opposite characteristics in terms of the dynamic stiffness of the inflatable curtain airbag, the sequential development process cannot avoid the iteration for dynamic stiffness optimization. Airbag internal pressure characteristics are can be used to evaluate the airbag performance in early stage of the development process, but they cannot predict dynamic energy absorption capability. In order to meet the opposite requirements for both FMVSS 226 and NCAP side impact test, a test and CAE simulation method for the inflatable curtain airbag was developed.

In recent years, products that make use of integrated safety that use the environmental data to optimize occupant restraints have been on the market. Pre-safe system in the integrated safety category is an adaptive and smart protection system that utilizes the occupant information and the monitoring information on the accident prediction. These pre-safe systems need the proper algorithm corresponding to the crash scenario for the crash unavoidable state. Due to the crash scenario categories for the real world accidents is quite various, the development of the algorithm and the occupant protection system to reduce the injury is quite complex and costly. For this reason, a development process for pre-safe related integrated safety systems demands new tools based on the biomechanics to help design and assessment. The virtual development and assessment process with a viewpoint on the efficiency of the restraint development has been developed.

The main role of CAB(side curtain airbag) is to protect the occupant's head in the event of side crash. The updated US NCAP for model year 2010 requires more extended coverage of CAB. It is not only required to cover the 50th%ile driver but also the 5th%ile driver and rear passenger. Although the general safety analysis model using only concerned sub-structure of the vehicle and prescribed structural motion is sufficient to handle frequent jobs, the analysis model with increased efficiency is needed when optimization is to be studied as it requires more runs and the model gets enlarged to consider extended sub-structure. In this study, three types of simplified analysis models are introduced. The first has an impactor which is composed of the head and neck with prescribed translational motions. It only uses the upper parts of the original sub-structure hence the run time is saved by 60∼70%.

A three-dimensional numerical method for the prediction of transient temperature of various brake components including brake fluid reached during the ALPINE braking mode in a ventilated disc brake assembly is presented in this paper. The ALPINE braking mode is the representative mountain descent simulation mode. For this precise analytical prediction of each brake component temperature during a repeated braking and heat soaking, a specified disc brake system is modeled including the brake disc, pad assembly consist of lining and back plate, piston and caliper body. Through this three-dimensional numerical method, a correlativity of the brake assembly geometry and the brake fluid temperature could be expected. Analytical results are compared with measured data with a good correlation. The effects of the various system parameters on the brake fluid temperature are also investigated with a three-dimensional computation.

A three-dimensional computational fluid dynamics(3-D CFD) model of the proton exchange membrane fuel cell(PEMFC) is presented to explain the characteristic of its behavior. Many researchers have numerically studied small(~10–50cm2) single cell PEMFC systems. But 3-D numerical model of the commercial-sized PEMFC with reacting area on the order of 200~ cm2 is still hard to perform effectively. This study applies 3-D CFD model to a commercial-sized(250cm2) PEMFC selected from research models to show its usefulness. Various types of bi-polar plate channel including standard serpentine shaped gas flow channel are proposed and examined. The model results indicate that forced gas flow induced by the modified gas channel improves mass transport of oxygen to, and water removal from, the catalyst layer, thus producing higher current density as compared with the initial shape. The effects of operating conditions like humidity, including temperature effect, and gas flow rates are also studied.