• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.63-71
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• 1998

In a diesel engine the phenomenon of spray impaction on a combustion chamber wall has been taken as an undesirable matter because of the deposition of fuel on the surfaces, and the subsequent slow evaporation and mixing with air resulting in unburned hydrocarbons. Therefore many researches have concentrated on avoiding fuel impaction on surfaces. On the contrary done a number of studies using spray wall impactions in a positive way, which makes the droplets smaller, changes the direction into free spaces far from the wall and also improves mixing with air. In this paper the angle variations of the impaction land sufrace prepared for the injection spray is analysed as a simulative manner. The spray dispersions, vapor distributions and flow fields are compared with impacting angle variation. The results show more angle give more vapor distribution until $15^{\circ}$.

• Composites Research
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• v.22 no.4
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• pp.27-32
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• 2009

Characterisation of the stress-strain relationship as well as crashworthiness of cellular polymer was investigated under constant impact energy with different velocities, considering inertia and strain rate effects simultaneously during the impact testing. Quasi-static and impact tests were carried out for two different density (64 $kg/m^3$, 89 $kg/m^3$) cellular polymer specimens. Also, the equations, coupled with the Sherwood-Frost model and the Impulse-Momentum theory, were employed to build the constitutive relation of the cellular polymer. The nominal stress-strain curves obtained from the constitutive relation were compared with results from impact tests and showed to be in good agreement.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.1
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• pp.171-180
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• 2001

Collision accident reconstruction algorithm are developed based on the deformation shape and severity of a car body. At first, the body stiffness equation representing the force-deformation relationship is derived using finite element analysis for head on collision of two cars. The database of deformation shapes and energies is constructed for five different collision configurations; each configuration contains three velocity conditions. Deformation shapes are obtained using a curve fitting method and result in cubic polynomials. Deformation energies are calculated using a stiffness equation and deformation data. Three algorithms are developed to reconstruct collision configuration compared with constructed database. The developed algorithms show reasonably good performance to find collisions conditions for some test problems.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.2
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• pp.189-197
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• 1996

In this study, the crashworthiness analysis was carried out for the hat type section side rails which had an important role of absorbing the impact energy during frontal crash. In case of a tapered hat type section model, numerical simulation models and test models were designed with varing design variables; welding pitch, taper angle, initiator shape, initiator location. The effect of variation of the design variables was investigated by quasi-static and dynamic test and numerical simulation.

• Journal of Auto-vehicle Safety Association
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• v.6 no.2
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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.

• 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)

• Journal of the korean Society of Automotive Engineers
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• v.18 no.4
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• pp.50-67
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• 1996

• Journal of the korean Society of Automotive Engineers
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• v.16 no.5
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• pp.30-40
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• 1994

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1122-1127
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• 2011

A bumper beam plays the important role of absorbing the bulk of bumper impact energy, so it is extremely important to determine the bumper beam section during the initial stage of car development process. This paper uses the Intermediate Response Surface Models (IRSM) technique for the bumper beam section optimization. By using this method, the nonlinear impact force-deflection curve is changed to an approximated curve. This can avoid the excessive 3D nonlinear FEM analysis during the optimization process. Then, the accuracy of the IRSM models is examined by comparing their results with those of the 3D nonlinear FEM. Finally it is shown that the proposed approach is effective to design the 2.5mph vehicle bumper section.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.2
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• pp.49-56
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• 2009

In this study, a side collision accident reconstruction using database based on the deformed shape information from the collision test using model cars is suggested. A deformation index and angle index related to the deformed shape is developed to set the database for the collision accident reconstruction algorithm. Two small size RC cars are developed to carry out the side collision test. Several side collision tests according to the velocity and collision angles are performed for establishing the side collision database. A high speed camera with 1000fps is used to capture the motion of the car. A side collision accident reconstruction algorithm is developed and applied to find the collision conditions before the accident occurs. Two collision cases are tested to validate the database and the algorithm. The results obtained by the reconstruction algorithm show good match with original conditions with regard to the velocity and angle.