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Numerical simulations are widely used to predict the performance of products in the automotive development process. In particular, ventilation and defrost performances of automotive HVAC system are developed according to design variables and environmental conditions based on CFD (Computational Fluid Dynamics). Recently, as improvement on both computer hardware performance and analysis technology continues, the usage of simulation has been increasing accordingly. However, the cost of software license also increases in such development environments. In this paper, we introduce our CFD program with OpenFOAM, which is the free, open source CFD software, to simulate flow characteristics of ventilation and defrost in automobile. This program includes self-developed GUI similar to commercial CFD code, two-layer realizable κ-ε turbulence model to secure numerical stability, and fluid film model to check the defrost phenomena with time dependence from OpenFOAM libraries.

The role of CAB is protecting the passenger's head during rollover and side crash accidents. However, the performance of HIC and ejection mitigation has trade-off relation, so analytical method to satisfy the HIC and ejection mitigation performance are required. In this study, 3 types of CAB were used for ejection mitigation analysis, drop tower analysis and SINCAP MDB analysis. Impactor which has 18kg mass is impacting the CAB as 20KPH velocity at six impact positions for ejection mitigation analysis. In drop tower analysis, impactor which has 9kg mass is impacting the CAB as 17.7KPH velocity. Acceleration value was derived by drop tower analysis and the tendency of HIC was estimated. Motion data of a vehicle structure was inserted to substructure model and the SID-IIS 5%ile female dummy was used for SINCAP MDB analysis. As a result, HIC and acceleration values were derived by MDB analysis.

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%.

Shape optimization is one of methods to reduce the vehicle weight, however the method is not used widely because the definition method of shape basis vector is too difficult. In this study, shape optimization and newly shaped FE model generation with morphing technique is investigated. First the advantage and disadvantage have been compared between commercial software, Hyper Morph and DEP Morpher. Second, morphing technique is applied to several automotive components. The research results show that newly shaped FE model generation with morphing technique is successful and very efficient to reduce the time of product development.

We performed numerical analyses using an explicit code to evaluate the cumulative impact damage of an automotive front-end bumper during low-speed crash events, as described by CMVSS215. The CMVSS215 regulation consists of a series of test cases for the same parts. To evaluate the crash performance of a bumper, we used a coupled numerical analysis scheme and considered several matters such as the removal of residual vibrations and the evaluation of the bumper back beam recovery. We also used an EWK rupture model in the PAM-CRASH code to improve our damage and fracture estimates. Tensile test experiments were conducted to tune the performance of the EWK rupture model; the resulting material properties and fracture criterion were incorporated into the numerical analyses of the low-speed frontal crash events. The coupled analysis scheme was verified by comparing the output with bumper impact test data.

Many automotive companies have recently introduced Virtual Product Development (VPD) techniques. The VPD helps engineers to reduce the number of design changes, speed up development time and improve product quality by utilizing CAE early in the design cycle before prototypes are ever created. In the VPD environment, however, simulation engineers inevitably perform a large number of analyses due to a number of design changes and validations of performance and reliability. In effect, the engineers have to follow many steps of analysis processes when using various kinds of simulation applications, which may require repetitious manual works such that it is easy to make mistakes. In an effort to solve these problems, automation software incorporating various types of analysis processes for automotive suspension components, DAAS (Durability Analysis Automation System) has been developed.

This paper is intended to find out the optimized restraint system for various crash conditions and to analyze the characteristics of those conditions numerically. 40km/h FF (Full Frontal crash), 56km/h FF and 64km/h ODB (Offset Deformable Barrier crash) conditions have been considered with 5th%ile female, 50th%ile male and 95th%ile male dummies on driver side. The vehicle lay out and crash pulses came from a compact passenger car. The restraint system was focused on the driver side airbag and seat belt. MADYMO 3D was used in this study for simulation.