• Proceedings of the KSR Conference
• /
• 2009.05a
• /
• pp.1624-1633
• /
• 2009

Brake system in railway train operates to reduce the speed of the train or to stop the train via changing the kinematic energy into heat energy for emission and so brake system makes an important rule to transport passenger and cargo for safety operation. Recently operators have a matter of grave concern for the verification of performance in brake system. To verify the exact performance of brake system, most of brake test has been carried out on real operating track condition. Therefore we will determine the braked weight of indirect brake system applied in Iran DMU(Diesel Multiple Unit) in accordance with mc leaflet 544-1, which is to enable Iran DMU to achieve the required braking distances in defined situation.

• Journal of the korean Society of Automotive Engineers
• /
• v.23 no.3
• /
• pp.38-42
• /
• 2001

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.2
• /
• pp.666-671
• /
• 2014

Using positive temperature coefficient (PTC) heater as supplementary heating for diesel engine vehicles with low heat source is a good method to enhance the heating performance during cold start. In this study, the PTC elements were made by using screen printing process for forming ohmic contact layer, and prototype of PTC heater was designed and made for a diesel engine vehicle. In process of designing the PTC heater, the thermal flow analysis of PTC element modules was conducted for verifying the effect of the shapes of contact surface between each of the components (cooling fin, insulator, ceramic element). We also investigated the performance characteristic (heating capacity, energy efficiency, pressure drop) of the PTC heater through the experiments. Therefore, the experimental results indicated that prototype of PTC heater had satisfactory performance. This study will be basis for improving the manufacturing process and increasing the performance of the PTC element and heater.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.3
• /
• pp.373-378
• /
• 2013

The speed change performance of transmissions has become a serious issue because of the increase in the inertia moment that has accompanied increases in engine output and transmission size. Therefore, it is necessary to develop better wear resistant friction materials. In this study, an appropriate sintered friction component for the synchronizer ring of a diesel manual transmission was developed, and its bonding characteristics were analyzed. That is, a process for bonding an Fe-based base material and Cu-based sintered friction material was developed. BSE and EDX analyses of this bonding layer were conducted, along with a shear strength test, to determine the bonding characteristics.

• Journal of the Korea Convergence Society
• /
• v.10 no.3
• /
• pp.177-184
• /
• 2019

The Defense Technology Security Act was enacted in 2015 to protect the defense industrial technology from being duplicated or interfering technologies being developed, which prevents its value and utility from deterioration and prevents inappropriate export. Defense industrial technology refers to technology that should be protected for national security among the national defense science and technology related to the defense industry. However, technical identification criteria of identification and management system of protection technology are not regulated. Therefore, in this study, through the Delphi survey, diesel engine core technology identification criteria related to the high efficiency internal combustion engine propulsion technology among the 141 defense industrial technologies is established to improve the identification and management system of the technology to be protected among the defense industrial technology protection system. As a result of the study, operational operability, durability, safety, sequencing and modularization were established as diesel engine core technology identification criteria.

• Journal of Energy Engineering
• /
• v.24 no.2
• /
• pp.144-153
• /
• 2015

At low temperature, Wax build-up and settling can affect adversely the cold weather performance of the diesel vehicle. In this study, we test the cold properties of diesel by blending ratio of biodiesel, kerosene and WAFI. Also, we test the cold weather performance for diesel vehicle by fuel cold properties. Cold properties of diesel are improved by adding the WAFI, kerosene and get worse by adding the biodiesel. WAFI is effective to improve a cold filter plugging point(CFPP) and Kerosene is effective to improve a cloud point(CP). CFPP and pour point(PP) are related to cold weather performance of diesel vehicle but CP is unrelated. CFPP indicate a limit temperature of vehicle driving possibility.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2003.05b
• /
• pp.109-110
• /
• 2003

우리나라에서의 철도는 도로교통에 비해 수송분담율이 상대적으로 낮지만, 2001년을 기준으로 1년 동안 824만 명을 수송하여 전체 여객 수송량의 약 6.2 %를 차지하고 있다. 최근 연구결과 비도로용으로 사용되고 있는 디젤엔진이 NOx와 입자상 오염물질 배출의 주요한 오염원으로 밝혀졌다. 국내외적으로 대기오염원 중 자동차나 트럭 등 도로용 차량에서 배출되는 오염물질에 대해서는 오래 전부터 관심을 기울여 왔지만, 디젤기관차, 선박 및 경작, 건설, 벌목, 채굴 장비 등을 포함하는 비도로용 이동오염원에 의한 오염물질 배출제어에 관해서는 논의가 거의 이루어진 적이 없었다. (중략)

• Journal of Power System Engineering
• /
• v.13 no.4
• /
• pp.5-10
• /
• 2009

Urea-SCR system, the selective catalytic reduction using urea as reducing agent, is a powerful technique to reduce nitrogen oxides(NOx) emitted from diesel engines. However, a tank of urea(32.5 wt%)-water solution can be frozen in low ambient temperature levels of below $-11^{\circ}C$. The purpose of this study is to understand freezing and melting phenomena of the urea-water solution, and its can be applied to get the urea-water solution from frozen it within 5 minutes after cold start. Factors considered were the type of heater and the urea tank shape. From the results, it was found that melting volume of cartridge heater B during 5 minutes of heating period was 83ml when supplying electric power of 150W. Horizontal heater B, which was put in the narrow bottom space of the tank T1, had fast melting characteristics.

• Tribology and Lubricants
• /
• v.11 no.1
• /
• pp.1-4
• /
• 1995

각 나라 자동차 엔진메이커들은 그 나라의 기후, 환경, 도로사정 등 그 중요도에 따라 독자적인 성능규격을 실시하고 있으며 특히 우리나라도 기후, 지형 및 사용연료인 디젤유황함량 등의 조건에 맞는 공동의 독자적인 엔진 test method 및 규격제정이 필요한 시기가 도래하였다고 보며, 국내 자동차 메이커들이 전 세계로 수출하는 과정에서 그 해당나라의 엔진요구 규격을 잘 인식하고 자동차수출에 따른 AS 및 오일추천을 정립하여, 오일에 의한 엔진트러블 등을 방지해야 할 것이며, 국내에 유럽 및 일본식 엔진이 70~80% 시장성을 갖고 운행되고 있다는 점을 인식하여 그 적합한 유럽의 CCMC 규격과 유럽의 유명 자동차메이커의 규격에 대해 잘 알아야 할 것이며, 엔진오일의 성능등급에 대한 잘못된 인식과 오일선택으로 고가 차량의 엔진트러블 및 잦은 수리로 소비자나 국가적으로 경제적 손실의 발생을 방지하는 디젤엔진오일의 올바른 선택과 요령을 정리하였다.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.20 no.5
• /
• pp.36-43
• /
• 2012

In this work the mixing and flow characteristics of a vane-type static mixer were investigated numerically for the reduction of NOx in the SCR-system of the diesel engines. The mixer was located in the 57 times pipe diameter away from the inlet. The analysis were performed by changing such various parameters as vane shape, angles, blockage ratio and location of the vane. The flow structure through the mixer was characterized by uniformity index and pressure drop. The results show that uniformity index and pressure coefficient are substantially influenced by the vane shape, angle, blockage ratio and position of the vane of the mixer.