• Transactions of the Korean Society of Automotive Engineers
• /
• v.17 no.5
• /
• pp.133-139
• /
• 2009

When two cars impact each other, it is usually known smaller vehicle's passenger likely to be more seriously injured than bigger one's. Generally it is known that SUVs and Light Truck Vehicles (LTVs) are bigger and heavier than passenger vehicles and their drive height such as bumper rail and side member, and front end stiffness are higher than those of passenger vehicles. Because of these characteristics the occupants of passenger vehicle struck by SUVs or LTVs are more likely to experience severe injury or fatal injury. To evaluate SUV and LTV's aggressivity to passenger vehicle, SUV to passenger vehicle and LTV to passenger vehicle head-on crash test have been carried out. And finally the way how to reduce incompatibility between SUV and LTV and passenger vehicles is suggested.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.9 no.5
• /
• pp.62-74
• /
• 2001

In this study, the prediction of performances and emissions of the gasoline engine of a light passenger car has been accomplished. The method of characteristics including friction, heat transfer, area change and entropy gradients was used to analyze the flow in the intake and exhaust systems. For in-cylinder calculation, the single-zone model was adopted for the periods of the intake, exhaust, compression and the expansion of the burnt gas and the 2-zone expansion model was applied to the period of combustion process. The simulation program was verified by comparison with the experimental values both for the naturally aspirated engine and the turbocharged engine showing good agreements. Using the simulation program, multi-valve system and turbocharging were examined as a means of increasing engine Performances.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.6
• /
• pp.40-50
• /
• 2000

In this study, as a means of increasing engine power, turbocharging was applied to the gasoline engine of a light passenger car which was originally naturally aspirated. Also the catalytic convertor was applied to improve the exhaust emission characteristics. The comparison of the performance characteristics between the burbocharged engine with catalytic convertor and the naturally aspirated engine was made over the wide range of operating conditions. The results showed considerable increase of the output performances at full load condition by trubocharging while slight losses were observed at part load conditions.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.19 no.2
• /
• pp.98-104
• /
• 2011

The introduction of a diesel engine into the passenger car and light duty applications in the United States involves significant technical challenges for the automotive makers. This paper describes the SCR System optimization procedure for such a diesel engine application to meet Tier2 Bin5 emission regulation. A urea SCR system, a representative $NO_x$ reduction after-treatment technique, is applied to a 3.0 liter diesel engine. To achieve the maximum $NO_x$ reduction performance, the exhaust system layout was optimized using series of the computational fluid dynamics and the urea distribution uniformity test. Furthermore a comprehensive simulation model for the key factors influencing $NO_x$ reduction performance was developed and embedded in the Simulink/Matlab environment. This model was then applied to the urea SCR system and played a key role to shorten the time needed for SCR control parameter calibration. The potential of a urea SCR system for reducing diesel $NO_x$ emission is shown for FTP75 and US06 emission standard test cycle.

• International Journal of Automotive Technology
• /
• v.8 no.1
• /
• pp.67-73
• /
• 2007

This study analyzes the interior noise that is generated during acceleration of a passenger car in terms of car body structure and panel contribution. According to the transfer method, interior noise is classified into structure-borne noise and air-borne noise. Structure-borne noise is generated when the engine's vibration energy, an excitation source, is transferred to the car body through the engine mount and the driving system and the panel of the car body vibrates. When structure-borne noise resonates in the acoustic cavity of the car interior, acute booming noise is generated. This study describes plans for improving the car body structure and the panel form through a cause analysis of frequency ranges where the sound pressure level of the rear seat relative to the front seat is high. To this end, an analysis of the correlation between body attachment stiffness and acoustic sensitivity as well as a panel sensitive component analysis were conducted through a structural sound field coupled analysis. Through this study, via research on improving the car body structure in terms of reducing rear seat noise, stable performance improvement and light weight design before the proto-car stage can be realized. Reduction of the development period and test car stage is also anticipated.

• Journal of the korean Society of Automotive Engineers
• /
• v.5 no.2
• /
• pp.15-20
• /
• 1983

The nature and the sources of sound in cars is discussed in the light of many previous works, and the importance of the system resonances inside cars is suggested. An investigation of a 'boom' problem in a small size passenger car is described. It was established that the 'boom' frequencies coincided with engine firing frequency and also with several system resonances. To find out main transmission path of the noise to the car interior, various possible sources were eliminated from the investigation by means of simple modification to the vehicle. Data on the structural modes of the body, and the acoustic modes of the passenger compartment at various forcing cases were obtained to provide better understanding of the problem. It was found that the acoustic resonance responsible for the boom was controlled largely the bending motion of the floor. To investigate the effect of the structural modification to the acoustic response, center floor of the car was reinforced. a great reduction of the noise inside the car especially at the offending speed range, was achieved by this modification.

• Journal of the Korea Safety Management & Science
• /
• v.14 no.2
• /
• pp.35-40
• /
• 2012

The aims of this study are to investigate stereotypes of motion-direction and real motion-directions for seven principal controls in passenger cars, and to compare the stereotypes and real motion-directions for the controls. The stereotypes were obtained by using questionnaire survey, in which 385 subjects participated. The real motion-direction data were gathered for 64 passenger cars including RVs and SUVs. The results showed that while there are dominant motion-directions for head light, door key and door lock controls, dominant motion-directions are not found for other controls investigated in this study. The stereotypes of motion-directions for seven controls obtained in this study were much different from those of the real data. Furthermore, the stereotypes for wiper, head light and high beam controls based on the questionnaire survey were opposite to the real motion-directions.

• Journal of the Korea Safety Management & Science
• /
• v.15 no.2
• /
• pp.63-69
• /
• 2013

The purposes of this study are to survey stereotypes of control-display relationships for seven principal controls in passenger cars using the paper-pencil and hardware tests, and to examine stereotype strength of the paper-pencil test through comparing the stereotypes for the controls derived by the two methods. Ninety two and 60 college-aged students participated in the paper-pencil test and the real car simulation of the hardware test, respectively. There are dominant motion-directions for all controls in the paper-pencil test, while in the hardware test, there are dominant motion-directions for six controls including head light, high beam, door window, ignition key, door key and door lock controls. The stereotypes of motion-directions for six controls obtained by the paper-pencil test were the same as or similar to those by the hardware test. It was inferred from this that the congruence of the stereotypes by the two methods might be attributed to two simple motion-direction principles of 'clockwise for increase' and 'upward for increase.' Although it is known that the hardware test would be best for obtaining accurate stereotypes between controls and displays, this study implies that if the paper-pencil test is well designed, the paper-pencil test can produce the same results as the hardware test at low cost and without consuming time.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2006.11a
• /
• pp.680-685
• /
• 2006

The latest trend in the automotive industry demands the development of high stiffness car bodies and the securement of inter-system performance for low vibration and noise vehicles. This demand, however, conflicts with need for light weight design and greater fuel efficiency, thus raising the importance of optimization design to satisfy both developmental goals. We chose two European medium sedans, which has gasoline engine and diesel one, to elucidate the noise characteristics of diesel passenger cars, whose sales have been increasing in both Korea and Europe. In the present study a systematic experiment was conducted to analyze the noise characteristics in diesel cars. we made it possible for differentiating car management according to customer demand while allowing for improved commercial feasibility. it was possible to improve interior noise by 2 dB(A) on average sound pressure level. As a result, by 4% higher on articulation index(AI).

• Journal of Auto-vehicle Safety Association
• /
• v.3 no.2
• /
• pp.11-16
• /
• 2011

In recent years, rapid-increasing market share of compact cars and SUVs has brought for both consumer and automaker to pay more attention on crash compatibility between the compact passenger vehicles and the light trucks (i.e., Pickups and SUVs). Vehicle compatibility regarding both self and partner protection in frontal crash of different class vehicles is one of hot issues in vehicle safety. Furthermore, it is expected that the amendment of UNECE-Regulation 94 to implement compatibility issues in couple of coming years. In this study, conceptual design of compatibility compliant frontal vehicle structure which subjects to improve? the distribution of frontal crash loading and structural engagement between vehicles is introduced. The effects of proposed vehicle structure on both possible candidates (i.e. FWRB, FWDB and PDB) for a compatibility evaluation test procedure and car-to-car crash are also investigated.