• Proceedings of the ESK Conference
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• 1995.10a
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• pp.91-100
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• 1995

자동차의 안전도는 전통적으로 정면 충돌시 승객의 보호 정도를 가지고 비 교 된다. 그러나 근래에 와서는 다양한 사고에 의한 승객의 피해를 볼 때 정면 과 더불어 측면 충돌시의 피해를 무시할 수 없는 상태에 이르렀다. sled tests 등을 통해서 정면 뿐만 아니라 측면 충돌의 영향도 파악하고 있으나 정면 충돌보다 측면 충돌에 대해 승개 보호 장치의 개발이 미흡한 것이 현실이다. 본 연구에서는 현실적으로 보다 효과적인 occupant (운전자 및 승객) restraint system을 computer 모의 실험을 통해서 제안하고자 하였다. 기존의 안전시스템인 lap/shoulder belt system과 Air cushion에 의한 실험은 다각도로 연구되었다. 그러나 측면 충돌에서 Air Bag에 의한 충돌 감소 영향은 정면 충돌에 비해 적어지게 되어 상체 측면 보호 장치가 필요하게 된다. 본 연구에서는 운전자의 lap/shoulder belt system과 Air Bag에 의해 구속되는 dummy를 가지고 다양한 측면 충돌 각도 (0 .deg. , 15 .deg. , 30 .deg. , 45 .deg. , 70 .deg. )에서 실험이 수행되었다. 또한 각 충돌각에 대해 기존 Restraint System에 상체 측면 보호 장치(seat wing)를 포함하여 실험을 수행 하였다. 이에 대한 각각의 영향, 그리고 승객 손상도 분석 및 평가를 통하여 보안된 측면 충돌 보호 restraint system의 필요성과 그 효과를 제시하고자 한다. 실험결과 에 의하면 정면보다 측면에서 충돌하였을 경우 보조 구속 시스템인 seat wing으로 인 해 측면보호는 물론 occupant는 정면으로 나가게 개선되어 구속 시스템으로써의 이점이 확대되고 shoulder blet 또는 dummy의 감속을 통제하는 Air Bag의 잠재적인 이점이 더욱 확대되었음을 보여주고 있다. 그러나 design 단계에서 편안함, 안락감 등의 문제들과, 다른 실용적인 면에 대한 계속적인 연구가 필요하다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.4
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• pp.353-360
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• 2011

The prediction of binary droplet collisions is important in the formation of falling drops and the evolution of sprays. The droplet velocity, impact parameter, and drop-size ratio influence the interaction between the droplets. The effect of these parameters results in complicated collision phenomena. Droplet collisions can be classified into four types of interactions: bouncing, coalescence, reflexive separation, and stretching separation. In the present study, the interfacial flow problem of the droplet collision was numerically simulated by using the level set method. 2D axisymmetric simulations on the head-on collisions and 3D simulation on the off-center collisions were performed. The numerical results of droplet behavior after the collision agreed well with the experimental and analytical results. The mixing of the mass of the initial droplets after the collision was also predicted by using different species index of colliding droplets.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.530-537
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• 2016

This study investigates frontal crashes, analyzes the driver's action related to the change of the collision direction and determines the severity of (bodily injury). This study was conducted from August, 2013, to January, 2014, and the data for the car damage and human body damage were collected by emergency medical teams. In terms of data collection, we collected the accident vehicle, crash direction, body damage, etc., based on the Korea In-depth Accident Study (KIDAS) and Injury Severity Score (ISS). We used Minitab 17 and SPSS 22.0 to do the frequency analysis and ANOVA. In the analysis results, the prevalence of frontal collisions was 55.8% and mostly occurred in the 12 o'clock direction. In the analysis of the frontal crash direction according to age, the average ages for the 11, 12 and 1 o'clock directions were $46.46{\pm}13.47$, $44.43{\pm}13.40$ and $52.46{\pm}12.04$, respectively, so the older age drivers had a high probability of the accident occurring in the 1 o'clock direction. In the analysis of men's frontal collision direction according to age, the average ages in the 11, 12 and 1 o'clock directions were $47.10{\pm}13.88$, $45.24{\pm}13.78$ and $55.73{\pm}13.38$, respectively, so older aged men had a high probability of having collisions in the 1 o'clock direction. However, the statistical analysis of the frontal crash direction according to age in women didn't show any meaningful trend. When comparing the ISS according to age of the men and women in the collision direction, the men were less likely to have a 12 o'clock collision when $ISS{\geq}9$ and more likely to have a 1 o'clock collision when ISS<9. As a result, frontal crashes are more likely to occur in the 12 o'clock direction and the ISS decreases because the likelihood of frontal crashes in the 1 o'clock direction increases with increasing age. Therefore, when men recognize that they are heading for a 12 o'clock direction collision, they try to steer to the left to reduce the body damage.

• Journal of the korean Society of Automotive Engineers
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• v.18 no.4
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• pp.36-49
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• 1996

본 고에서는 정면충돌.측면충돌 등과 같은 각종 충돌상황시의 승객보호기준과 모델링 및 해석결과 등을 승객거동해석결과와 차체충돌해석결과를 연계하여 이를 초기설계에 이용할 수 있는 방안을 제시하고자 한다. 차체충돌해석 소프트웨어 개발에 관해서는 계속되는 글에서 설명될 것이다.

• Journal of Auto-vehicle Safety Association
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• v.8 no.3
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• pp.33-38
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• 2016

Recently, development in vehicle safety could increase interest in children's safety in vehicle collisions. But the research of children safety in vehicle collisions is not being conducted as many as that of adult's. Especially the study for the vehicle crash was not much. This study focused on the comparison of child safety between test protocols to evaluate children's safety in crash test. Injuries of Q6 and Q10 dummy were evaluated using FFRB (Full frontal rigid barrier) test and 40% ODB (Offset deformable barrier) test with one model vehicle. Even though the limit number of test, the tendency of injury criteria of Q6 and Q10 dummy between the test protocols was not conformed but injury criteria of Q6 and Q10 were not same between FFRB and 40% ODB.

• Composites Research
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• v.21 no.1
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• pp.22-29
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• 2008

This paper presents the evaluation of crashworthiness and rollover characteristics of low-floor bus vehicles made of aluminum honeycomb sandwich composites with glass-fabric epoxy laminate facesheets. Crashworthiness and rollover analysis of low-floor bus was carried out using explicit finite element analysis code LS-DYNA3D with the lapse of time. Material testing was conducted to determine the input parameters for the composite laminate facesheet model, and the effective equivalent damage model for the orthotropic honeycomb core material. The crash conditions of low-floor bus were frontal accident with speed of 60km/h. Rollover analysis were conducted according to the safety rules of European standard (ECE-R66). The results showed that the survival space for driver and passengers was secured against frontal crashworthiness and rollover of low-floor bus. Also, The modified Chang-Chang failure criterion is recommended to predict the failure mode of composite structures for crashworthiness and rollover analysis.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.197-202
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• 2010

Post release mechanism is generally used to reduce the severity of the occupant of an errant vehicle impacting a roadside posts. The 820kg-50km/h head-on impact simulations were made using LS-DYNA program for the posts of 101.6mm Dia(t=4.0mm) with and without clip-type release mechanism. The simulation result was compared with impact test result to enhance the credibility of simulation model. The study shows that the high impact severity (THIV, PHD) and excessive deformation threatens the safety of the occupant when a car impacts a rigidly connected posts, while a post with clip-type slip base reduce the impact severity to a safe level.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1999.06a
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• pp.25-30
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• 1999

자동차의 정면 충돌시 발생하는 충돌에너지를 흡수하여 인명을 보호하기 위한 장비중 구조 역학적 관점에서 고려될 수 있는 것으로 범퍼와 사이드멤버(Side Member)가 있다. 이들중 범퍼는 시속 8km/hr 이하의 저속 충돌시에 탄성 변형에너지로서 충돌에너지를 흡수하는 역할을 하나, 그 이상의 고속 정면 충돌시에는 일반적으로 사이드멤버가 충돌에너지의 60∼70%를 부재의 연속적인 대변형에 의한 소성에너지에 의해 흡수하고 있다. (중략)

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.175-186
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• 2010

When a rigid post is exposed to traffic, it is hazardous not only to head-on impacts but also to side impacts. Clip-type slip base is an effective measure to reduce the severity of head-on impacts and side impacts as well because of its multi-directional release mechanism. Side impact tests were conducted and the results were analysed to demonstrate the hazardousness of a rigid post to a side impact and the crash worthiness of a post having clip-type slip base. For that, side impact test standard was made adapting the NCHRP Report 350, and 820kg-50km/h side impact tests were made for posts of D101.6mm(t=4.2mm) with and without slip base. Additionally, 35km/h side impact to the same post with slip base was conducted to check whether the clip-type slip base release mechanism works properly to the low impact speed. The tests revealed that the rigidly connected post was very hazardous to side impact while the post with the clip-type slip base reduced the impact severity tremendously.

• Journal of Auto-vehicle Safety Association
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• v.14 no.1
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• pp.62-67
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• 2022

This study is to construct the simple estimating model for the HIC15 of the driver dummy using the frontal impact test results. Test results of 9 vehicles of Hyundai Sonata from the MY2002~MY2020 USNCAP are utilized for constructing the linear regression model. The average accelerations extracted from the vehicle crash pulses are handled as the main factors. The average accelerations of 10 ms interval within 0~100 ms are calculated from the crash pulse data of 9 vehicles. The present estimating model of the HIC15 using the average accelerations of 10 ms interval in the 0~80 ms range shows good agreement with the tested value within 2.4% maximum error.