• 한국분무공학회지
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• 제25권1호
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• pp.34-39
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• 2020

Automotive manufacturers are applying technologies for greenhouse gas reduction such as vehicle weight reduction, engine downsizing, direct injection technology, variable valves and transmission performance improvement to achieve the targets for enhanced greenhouse gas and fuel consumption efficiency. In this paper, compared and analyzed greenhouse emissions according to engine capacity, engine displacement, curb weight and sales volume of hybrid and internal combustion engine passenger vehicles. Hybrid emit 32~39% less greenhouse gas than internal combustion engines through the combined mode test method. Hybrid electric vehicle's curb weight was about 7% heavier on average for the same engine displacement, while greenhouse gas was about 36% lower. It was confirmed that in order to reduce the emission of pollutants of greenhouse gases as well as the air pollutants, it is necessary to expand the supply of eco-friendly vehicles.

• 한국전산구조공학회논문집
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• 제30권4호
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• pp.297-306
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• 2017

국내 고속도로 콘크리트 중앙분리대는 SB5-B(270kJ)의 충돌등급에 저항하도록 설계되어 있다. 그러나 최근 대형 화물차량의 충돌사고가 지속적으로 증가하는 경향을 보이고 있어 SB6(420kJ) 등급으로의 상향이 필요하다. 충돌등급 상향을 위한 새로운 중앙분리대 단면을 제시하기 위해서는 실제 충돌시험을 수행하여 기준 통과여부를 결정하며, 충돌시험 수행을 위한 적정 단면을 제시하기 위해서는 충돌해석을 통해 선정한다. 이러한 충돌해석의 정확도 향상을 위해서는 차량 모델, 콘크리트 단면 열화상태, 콘크리트 피복 두께 등 다양한 변수에 대한 정확한 변수 선정이 필요하다. 따라서 본 연구에서는 공차 중량, 단면 열화, 콘크리트 피복 두께에 대한 변수연구를 수행하여 충돌저항성능 저감을 확인하였다. 전체 중량뿐만 아닌 공차 중량에 따라 중앙분리대의 충돌저항성능에 차이가 있는 것으로 확인되었으며, 10cm 이하의 콘크리트 피복 두께에서는 충돌저항성능이 민감하게 증가 또는 감소한다. 단면 열화가 발생할 경우 중앙분리대의 충돌저항성능의 감소가 발생하여 열화정도에 따른 보수 및 보강이 이루어져야 하는 것으로 판단된다. 따라서 콘크리트 구조물과 차량의 충돌해석을 수행할 경우 트럭의 공차중량 비율, 콘크리트의 피복두께 및 열화에 대한 영향이 상세하게 고려될 필요가 있음을 확인하였다.

• 한국수소및신에너지학회논문집
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• 제29권5호
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• pp.497-502
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• 2018

In Korea, passenger car and van using LPG fuel including taxi constantly increased due to the high cost of fuel. Recently, the emission standard has continuously tightened in the world. In this investigation was conducted the greenhouse gas emission characteristics of LPG vehicles according to the displacement and weight. Exhaust emission characteristics of 13 test LPG vehicles from about 1.0 L to 3.0 L displacements were measured and analyzed by using chassis dynamometer and emission analyzer. It is revealed that the greenhouse gas emission was showed the increasing tendency as the displacement and curb weight increased. Also, greenhouse gas emission of SC03 driving cycle has highest value and that of HWFET driving cycle shows the lowest value.

• 한국산학기술학회논문지
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• 제17권9호
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• pp.133-140
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• 2016

국토교통부에서는 교통약자의 이동 편의 증진을 위하여 승하차에 편리한 저상버스를 도입하였다. 표준모델로 고시된 저상버스는 11 m 급, 압축천연가스(CNG, Compressed Natural Gas)를 사용하는 차량으로 개발되었다. 11 m 급 저상버스는 길이 좁은 농어촌 및 산간지역 도로여건에서의 운행과, CNG 연료의 특성상 충전시설의 한계로 인하여 연료보급의 단점을 가지고 있다. 본 연구에서는 국토교통부에서 교통약자의 이동편의 증진을 위해 진행하는 중형저상버스 표준모델 기술개발 과제의 일환으로 (주)타타대우상용차에서 제작한 LF-40을 대상으로 공차(CVW, Curb Vehicle Weight), 반적차(HVW, Half Vehicle Weight), 적차(GVW, Gross Vehicle Weight) 3가지 중량조건으로 실도로 타행주행을 통하여 주행저항 값을 취득하였고, WHVC, NIER-06, 복합 에너지 소비효율 측정 대상차량 외 차량의 에너지 소비 효율을 측정하기 위한 시험 방법인 정속주행 (60 km/h)모드를 사용하였다. 시험 결과 공차상태의 연비가 가장 좋았으며, 대표적으로 WHVC 모드에서는 공차대비 반적차는 3.5 %, 공차대비 적차는 12 % 연비소모율의 차이를 보였다. 60 km/h 정속 주행모드에서는 다른 시험모드와 다르게 공차보다 반적차의 연비가 높은 것으로 측정되었다. 추후 배출가스 데이터의 분석이 필요할 것으로 판단된다.

• International Journal of Automotive Technology
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• 제7권4호
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• pp.459-468
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• 2006

The objective of this paper is the development of the forward-looking dynamic simulation model of a hybrid electric vehicle(HEV) for a fuel economy study. The specification of the vehicle is determined based on two factors, engine peak power to curb weight ratio and specific engine power. The steady state efficiency models of the powertrain components are explained in detail. These include a spark ignition direct injection(SIDI) engine, an integrated starter alternator(ISA), and an infinitely variable transmission(IVT). The paper describes the integration of these models into a forward facing dynamic simulation diagram using the AMESim environment. Appropriate vehicle and driver models have been added and described. The controller was designed in Simulink and was combined with the physical powertrain model by the co-simulation interface. Finally, the simulation results of the HEV are compared with those of a baseline vehicle in order to demonstrate the fuel economy potential. Results for the vehicle speed error and the fuel economy over standard driving cycles are illustrated.

• International Journal of Automotive Technology
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• 제7권6호
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• pp.715-720
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• 2006

This research investigates injury values and vehicle deformation for vehicle frontal crash compatibility. To investigate compatibility in an individual case, it is possible to impact two vehicles and evaluate the injury values and deformations in both vehicles. In this study, four tests were conducted to evaluate compatibility. A large and mini vehicle were subjected to a frontal car-to-car crash test at a speed of 48.3 km/h with an offset of 40%. An inclination car-to-car crash test using the large and small vehicle were conducted at 30 km/h at a $30^{\circ}$ angle. The results of the 48.3 km/h, car-to-car frontal crash revealed extremely high injury values on the chest and upper leg of the Hybrid III 50% driver dummy with seatbelt in the mini vehicle compared to the large vehicle. For the 30 km/h, car-to-car inclination crash, however, injury values in the small vehicle were 1.5 times higher compared to the large vehicle.

• 한국자동차공학회논문집
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• 제14권6호
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• pp.190-194
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• 2006

This research investigates vehicle structure acceleration and vehicle deformation with RCAR crash test. To investigate vehicle damage characteristics in an individual case, it is possible to RCAR low speed crash test. In this study, two tests were conducted to evaluate difference between RCAR new condition and RCAR old condition. A two large vehicles were subjected to a frontal crash test at a speed of 15km/h with an offset of 40% $10^{\circ}$ angle barrier and flat barrier. The results of the 15km/h with an offset of 40% $10^{\circ}$ angle barrier revealed high acceleration value on the vehicle structure and high repair cost compared to the RCAR 15km/h with an offset of 40% flat barrier. So in order to improve damage characteristics in low speed crash of vehicle structure and body component of the monocoque type passenger vehicles, the end of front side member and front back beam should be designed with optimum level and to supply the end of front side member as a partial condition approx 300mm.

• 융복합기술연구소 논문집
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• 제8권1호
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• pp.5-8
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• 2018

Emissions of diesel vehicles have been regulated by NEDC mode for a long time. However, the NEDC mode has been known the control of emission reduction is not reflected properly on actual road conditions. For these reasons, diesel vehicle emissions are regulated in both NEDC mode and WLTC mode from 2017 to 2020, from 2020 onwards, the emissions of diesel vehicles will measure in WLTC mode only and will not be able to exceed 1.5 times the regulated value. The purpose of this study is to analyze the development trend of diesel vehicle after-treatment system in order to comply with the future regulations on diesel vehicle. As a result, it is essential to reduce the NOx emissions of diesel vehicles for Euro 6, the NOx emissions of the test vehicle equipped with SCR were 30% to 50% loss than the test vehicle equipped with LNT despite the higher curb weight and engine displacement.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1658-1662
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• 2007

The tire uneven wear has been an ongoing concern for a long time, and one of customer's complaints too. This paper deals with uneven wear improvement of passenger car tires, to have tested the tire wear levels by each wheel alignment set (according to changing toe and camber) using taxis. The pre-set wheel alignments on test vehicle were gained by energy friction simulation of tire. The result of this experiment was as follows : First, verified the effects of initial wheel alignment (adjusted at Curb Vehicle Weight) to minimize tire uneven wear. Second, tire uneven wear makes tire life much shorter than even wear does.

• 한국자동차공학회논문집
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• 제13권6호
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• pp.135-141
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• 2005

Currently many safety assessment tests are conducted by crashing a vehicle against a rigid or deformable barrier. It is quite rational to evaluate crash performance of a vehicle in a barrier test in terms of vehicle stiffness and strength. However, there has been a lot of debate on whether barrier testing is a duplicate of real world crash collisions. One of the issues is car to car compatability. There are two essential subjects in compatability. One is partner-protection when crashing into another vehicle and the other is self-protection when struck by another vehicle. When considering a car to car frontal crash between a mini car and a large heavy car, it is necessary to evaluate human body stiffness of each vehicle. In this study, in order to evaluate the compatability of cars in car-to-car crashes, four tests were conducted. Test speed of each car is 48.3km/h, and the overlap of the mini and large car is $40\%$, and the overlap of the small cars is $100\%$. In all tests, only a drive dummy is used. The test results of the car to car crash test show that vehicle safety standard of mini car is not satisfied compared with large heavy car and HIC value of mini car is higher than large car. In this case observed that the relatively lower stiffness and weight of the mini car resulted in absorbing a large share of the total input energy of the system when crashed into the large heavy car.