• 제목/요약/키워드: vehicle impact

검색결과 944건 처리시간 0.027초

Vehicle-induced aerodynamic loads on highway sound barriers part1: field experiment

  • Wang, Dalei;Wang, Benjin;Chen, Airong
    • Wind and Structures
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    • 제17권4호
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    • pp.435-449
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    • 2013
  • The vehicle-induced aerodynamic loads bring vibrations to some of the highway sound barriers, for they are designed in consideration of natural wind loads only. A field experiment is carried out with respect to three important factors: vehicle type, vehicle speed and the vehicle-barrier separation distance. Based on the results, the time-history of pressures is given, showing identical characteristics in all cases. Therefore, the vehicle-induced aerodynamic loads acting on the highway sound barrier are summarized as the combination of "head impact" and "wake impact". The head impact appears to have potential features, while the wake impact is influenced by the rotational flow. Then parameters in the experiment are analyzed, showing that the head impact varies with vehicle speed, vehicle-barrier separation distance, vehicle shape and cross-sectional area, while the wake impact is mainly about vehicle-barrier separation distance and vehicle length.

자동차 측면 충돌 안전도 평가 분석 (Safety Evaluation of Korean New Car Assessment Program - Side Impact)

  • 신재호;용기중
    • 자동차안전학회지
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    • 제6권2호
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    • pp.12-17
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    • 2014
  • The number of vehicle accidents related to the side impact has increased since 1990 in Korea, thus the side impact test has been performed as one of the major vehicle evaluations of the Korean New Car Assessment Program(KNCAP) in 2003. A total of 77 vehicles of eight different types(compact, small, semi-midsize, midsize, and large sedans and small, midsize, and large sports utility vehicles) were tested in side impact and side pole impact conditions. In this study, the head and thorax injury values(HICs and chest deflections) of the side impact tests performed between 2003 and 2013 were investigated in terms of vehicle type, test year, and test condition. The recent vehicles showed better safety performances(lower injury values) and similar injury patterns were obtained between side impact and pole side impact tests.

충돌시 3차원 거동특성 해석을 위한 모델링 (Three-Dimensional Modeling for Impact Behavior Analysis)

  • 하정섭;이승종
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 춘계학술대회 논문집
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    • pp.353-356
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    • 2002
  • In vehicle accidents, the rolling, pitching, and yawing which are produced by collisions affect the motions of vehicle. Therefore, vehicle behavior under impact situation should be analyzed in three-dimension. In this study, three-dimensional vehicle dynamic equations based on impulse-momentum conservation principles under vehicle impact are introduced for simulation. This analysis has been performed by the real vehicle impact data from JARI and RICSAC. This study suggested each system modeling such as suspension, steering, brake and tire as well as the appropriate vehicle behavior simulation model with respect to pre and post impact.

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차량용 MR충격댐퍼의 동특성 해석 (Dynamic Characteristic Analysis of MR Impact Damper for Vehicle System)

  • 송현정;우다윗;최승복
    • 한국소음진동공학회논문집
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    • 제16권7호
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    • pp.754-761
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    • 2006
  • This paper presents the dynamic characteristics of MR impact damper for vehicle collision system. Various types of mechanism have been proposed to reduce force transmitted to the vehicle chassis and finally to protect occupants from injury. In the case of head-on collision, the bumper makes main role of isolation material for collision attenuation. In this study, the proposed bumper system consists of MR impact damper and structures. The MR impact damper utilizes MR fluid which has reversible properties with applied magnetic field. The MR fluid operates under flow mode. The bellows is used for generation of fluid flow. A mathematical model of the MR impact damper is derived incorporating with Bingham model of the MR fluid. Field dependent damping force is investigated with time and frequency domain. The MR impact damper is then incorporated with vehicle crash system. The governing equation of motion of vehicle model is formulated considering occupant model. Dynamic characteristics of vehicle collision system investigated with computer simulation.

차량용 MR 충격댐퍼의 동특성 해석 (Dynamic Characteristic Analysis of MR Impact Damper for Vehicle System)

  • 송현정;우다윗;최승복
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.147-152
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    • 2006
  • This paper presents the dynamic characteristics of MR impact damper for vehicle collision system. Various types of mechanism have been proposed for reduce transmitted force to vehicle chassis and finally protect occupants from injury. In the case of frontal collision, the bumper make main role of isolation material for collision attenuation. In this study, proposed bumper system composed of MR impact damper and structures. The MR impact damper is to adopted MR fluid which has reversible properties with applied magnetic field. MR fluid operates under flow mode with Bingham flow and bellows is used for generation of fluid flow. Mathematical model of MR impact damper incorporated with MR fluid is established. Field dependent damping force is investigated with time and frequency domain. The MR impact damper is then incorporated with vehicle crash system. The governing equation of motion of vehicle model is formulated considering occupant model. Dynamic characteristics of vehicle collision system investigated with computer simulation.

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머리모형 충돌에 의한 자동차 접합유리의 실험적 연구 및 유한요소해석 (Experimental Study and Finite Element Analysis about Vehicle Laminated Glass Subject to Headform Impact)

  • 최지훈;오원택;김종혁;박종찬
    • 한국자동차공학회논문집
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    • 제25권3호
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    • pp.374-379
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    • 2017
  • In vehicle to pedestrian accidents, cracks occur in the vehicle laminated glass due to impact of a pedestrian's head. In this study, FMH(Free Motion Headform) was used to experiment on and analyze the crack patterns on a vehicle laminated glass that collides with an adult headform at speeds of 20 km/h, 30 km/h, and 40 km/h, respectively. Applying the acquired experimental data and material property of the vehicle laminated glass to the structural analysis program LS-Dyna, we could develop the FE model of vehicle laminated glass similar to real vehicle laminated glass. We could estimate the head impact velocity and pedestrian's vehicle impact velocity using the Madymo program.

차량 측면도어 임팩트 빔의 최적설계 및 측면도어 충돌실험에 관한 연구 (Study on the Optimization Design and Impact Experiment of Side Door for Impact Beam in the Vehicle Side Door)

  • 김재열;최순호
    • Tribology and Lubricants
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    • 제31권1호
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    • pp.13-20
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    • 2015
  • The impact beam, a beam-shaped reinforcement installed horizontally between the inside and outside panels of car doors, is gaining importance as a solution to meet the regulations on side collision of vehicles. In order to minimize pelvis injury which is the biggest injury happening to the driver and passengers when a vehicle is subject to side collision, energy absorption at the door impact beam should be maximized. For the inner panel, the thrust into the inside of the vehicle must be minimized. The impact beam should be as light as possible so that the extent of pelvis injury to the driver and passenger during side collision of the vehicle is minimal. To achieve this, the weight of the impact beam, has to be optimized. In this study, we perform a design analysis with a goal to reduce the weight of the current impact design by 30% while ensuring stability, reliability, and comparison data of the impact beam for mass production. We conduct three-point bending stress experiments on conventional impact beams and analyze the results. In addition, we use a side-door collision test apparatus to test the performance of beams made of three (different materials: steel, aluminum, and composite beams).

차량의 임팩트하쉬니스 성능 예측 연구 (A Study on the Prediction of the Impact Harshness for a Passenger Vehicle)

  • 김진홍;정일수;김명규;심정수;이상우
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 추계학술대회 논문집
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    • pp.613-616
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    • 2012
  • A multi body simulation (MBS) model is developed for predicting the impact harshness of the vehicle. Impact harshness is the vehicle performance to evaluate the impulsive vibration behavior during driving over an obstacle of the road. Thus, the approach is simulated on the time domain for considering the transient behavior of the vehicle. The validity of vehicle component modeling of bushes, dampers and structure flexibilities is verified. The simulations are compared with the test results in both of vertical and longitudinal directions. In particular, the vertical vibration of the vehicle is significantly affected by the body flexibility. Through the sensitivity analysis, main factors for the impact harshness performance are investigated.

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선행 차량의 후진에 의한 저속 충돌 시 탑승자 경추 상해에 대한 연구 (Occupant Neck Injury Assessment Caused by Backward Movement of a Preceding Vehicle at a Low Impact Velocity)

  • 김성진;전우정;박우식;서영일;손권
    • 한국자동차공학회논문집
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    • 제21권3호
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    • pp.66-73
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    • 2013
  • This study assesses neck injury of occupants in a real traffic accident case that a preceding vehicle moved backward and impacted a parked vehicle at a low velocity. This case is different from a case of whiplash injury caused by rear impact on vehicle. The impact velocity was estimated from damages of the two vehicle bumpers and the displacement of the parked vehicle was also estimated from CCTV images. MADYMO simulation was performed based on the vehicle specifications and investigation report. The comparison of neck flexion moments with the corresponding injury criteria revealed that occupants of the parked vehicle might have hardly neck injury.

주퇴충격하중을 받는 궤도차량 구조물의 천이응력해석 (Transient stress analysis of tracked vehicle structures under recoil impact load)

  • 이영신;김용환;김영완;김동수;성낙훈
    • 오토저널
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    • 제15권3호
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    • pp.111-119
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    • 1993
  • In this study, the transient impact structural stress analysis of tracked vehicle structures under recoil impact load is investigated. ANSYS, ABAQUS Code are used for modelling and analytical procedures. The highest maximum Tresca stress occurs on race ring portion and its stress level is (.sigma.$_{T}$)$_{max}$ =20-40kgf/m $m^{2}$. The second highest stress occurs on upper plate of chassis and down plate of turret. The maximum stress level increases with loading direction and elevation angle. The results from liner static load analysis are very much different with impact analysis. Therefore, the practical solutions of structures under impact load can be obtained by only nonlinear transient impact analysis. The impact stress analysis of the steel vehicle structures is conducted. The maximum stress level is less than (.sigma.$_T/)$_{max}$m $m^{2}$. So, the design concept of steel structures can be adapted for new alternatives.s.s.s..s.

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