http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
전자빔 합성 방식 연료전지 촉매 반응기의 냉각 성능 설계
배석정(Sukjung Bae),허형석(Hyungseok Heo),양대수(Daesoo Yang),윤영철(Yeongcheol Yoon) 한국자동차공학회 2022 한국자동차공학회 부문종합 학술대회 Vol.2022 No.6
For the purpose of reduction of fossil fuel-based energy share and ultimately taking it over, researches on fuel cells that convert chemical energy into electrical energy have been actively conducted over the past few decades. Catalyst used to activate the oxygen reduction reaction in the reduction electrode of the fuel cell is a core material that determines the power generation efficiency by allowing the chemical reaction rate to be adjusted. Hydrated electrons accelerated close to a light speed having a powerful reducing force among various chemical species generated by water decomposition are able to reduce metal ions in a short time by irradiating electron beams to an aqueous solution including a metal precursor, thereby uniformly producing nanometer-sized catalyst particles on the surface of carbon carriers. In this study, reactor cooling performance has been designed to remove the heat generated inside the reactor. Cooling performance characteristics of precursor sample of catalyst have been analyzed according to several reactor models. The performance analysis has been performed according to coolant inlet conditions and mixer geometries.
엔진 냉각수 제어 시스템의 제어 성능 및 연비 배출 가스 성능 평가
배석정(Sukjung Bae),김현철(Hyunchul Kim),김명곤(Myonggon Kim),허형석(Hyungseok Heo),이기수(Geesoo Lee),이헌균(Heonkyun Lee),홍성훈(Sunghoon Hong) 한국자동차공학회 2008 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
To achieve the goal to meet the worldwide demand for the improvement of fuel efficiency and the reduction of exhaust, the thermal management system of vehicle adopts an adjustable electronic thermostat to vary the valve-open temperature and full-open lift with the operating condition of the vehicle in this study. The control temperature of the engine coolant of the system has been lifted 20℃ than conventional mechanical system so as to improve the fuel efficiency 2% or more. This study describes the procedure of assessment of performance of thermal management system and compares the results of CVS-75 chassis dynamometer tests lor the vehicle ill which mechanical or electronic thermal management system installed.
배석정(Sukjung Bae),허형석(Hyungseok Heo),이동혁(Donghyuk Lee),이헌균(Heonkyun Lee),강태구(Taegu Kang),김태진(Taejin Kim) 한국자동차공학회 2011 한국자동차공학회 부문종합 학술대회 Vol.2011 No.5
A waste heat recovery system with Rankine steam cycles for improving the fuel efficiency of gasoline automobiles has been investigated. The system recovers waste heat from engine exhaust gas. The design point and the target heat recovery of an evaporator, which is a core part of the system, have been presented. A prototype evaporator was evaluated by an experiment. The inlet temperature condition of the boiler working fluid was set to a degree of subcool of 5 ℃. The exit condition was the degree of superheat, which was set at 5℃. Heat recovery and pressure drops of fluids were evaluated for varying flow rates and inlet temperatures of the exhaust gas. A prototype boiler was also evaluated in order to set an effective design for the layout of heat recovery system.
전기자동차용 6 ㎾급 CNT 히터의 내열 구조강도 해석 설계
배석정(Sukjung Bae),이현석(Hyunseok Lee),이준용(Junyong Lee),허형석(Hyungseok Heo),이병호(Byongho Lee),김영삼(Youngsam Kim) 한국자동차공학회 2021 한국자동차공학회 부문종합 학술대회 Vol.2021 No.6
Since electric vehicles lack of heat source as engine of internal combustion vehicles, additional electric heaters have to be used for cabin heating in winter. Thus PTC heaters, which heat air entering cabin by electric heating, are generally used in electric vehicles. However, the existing type of heaters require so high power consumption that the mileages of electric vehicles significantly decreases. Carbon nano tube heating elements generates heat to distribute temperature uniformly in their film geometries and improves heat-up rate compared to conventional PTC elements with their high thermal conductivity as described in our previous study dealt with performance assessment of the heaters. In this study, CNT heater alone model and controller integrated model with an additional controller part on the heater have been modeled and thermal stress analysis has been performed to ensure stability against thermal stress caused by temperature differences in comparison. The controller integrated model shows slightly lower maximum stress than heater alone model, which both model have the maximum values within the ranges of yield strength of the materials.
응축기 전면의 유동 불균일도를 고려한 자동차용 에어컨시스템 해석 프로그램 개발
배석정(Sukjung Bae),허형석(Hyungseok Heo),송경석(Kyungsuk Song) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
Recently, circumstances for heat exchanger (condenser) in automotive air conditioning system to work have become worse due to curtailment of engine room to enlarge cabin space, abridgement of grille opening to enhance aerodynamic efficiency and diversification of heat source for future fuel cell vehicles. The periods to develope the new cars have become increasingly shorter. These situations have brought the need of performance prediction technique for air conditioning system on board at design stage. This study has developed simulation program for air conditioning system with inlet air flow maldistribution of condenser. The program takes inputs such as air inlet velocity and temperature distribution of condenser and geometries of system components and gives various outputs such as temperatures, velocities and pressures of both fluids - air and refrigerant. Experiments utilizing environmental wind tunnel have been conducted for various working conditions of air conditioning system. The results from program analyses have good agreements with that from experiments. The flow maldistribution in air temperature and/or velocity deteriorates the system performance up to 5%.
열교환기 배치 구조에 따른 냉각 시스템 성능 시뮬레이션
배석정(Sukjung Bae),허형석(Hyungseok Heo),김현철(Hyunchul Kim),이기수(Geesoo Lee),이헌균(Heonkyun Lee) 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
This study has developed a simulation program for an engine cooling system considering the arrangement and configuration of air side heat exchangers such as air-cooled transmission oil cooler, condenser, and radiator. The program may be also used for the system performance analysis according to the configuration of the coolant side heat exchangers such as water-cooled transmission oil cooler, EGR cooler, and heater core. An experiment utilizing environmental wind tunnel has been conducted for the performance of the system according to the arrangement of air side heat exchangers in front of the radiator. An adjustment of the coolant loop can enhance the heat core performance up to 4%.
배석정(Sukjung Bae),이준용(Junyong Lee),허형석(Hyungseok Heo),이병호(Byungho Lee),김영삼(Youngsam Kim) 한국자동차공학회 2018 한국자동차공학회 학술대회 및 전시회 Vol.2018 No.11
Cabin heating of electric vehicles is supplied electricity from limited electrical energy as there is no heat source unlike one of conventional internal combustion vehicles. In the winter season with use of electric heaters, the one-time charging range is reduced by 20 to 50 percent, which is a major factor in the delayed expansion of the electric vehicle market. General requirements for electric vehicles should be low energy consumption, rapid heat generation to implement defrosting function, light, compact, etc. In order to develop an innovative cabin heater for electric vehicle, the carbon materials is employed in this study. Carbon film heaters have a stable resistance, and can operate normally except in the area if part of it is open circuit. In this study, the design of the air side heat transfer fins has been carried out for the development of CNT heater. Models based on the fin pitch has been constructed to design the optimum geometry, and the pressure drop characteristics was predicted according to air flow rate.
엔진 배기 폐열 회수 시스템 사이클 해석 프로그램 개발
배석정(Sukjung Bae),허형석(Hyungseok Heo),이헌균(Heonkyun Lee),이동혁(Donghyuk Lee),정영대(Youngdae Choung),황재순(Jaesoon Hwang) 한국자동차공학회 2010 한국자동차공학회 부문종합 학술대회 Vol.2010 No.5
The environment surrounding us reinforces gradually to meet exhaust regulations side and fuel efficiency side. The application of waste heat recovery system to recover waste heat from vehicle engine exhaust has been a part of enormous technical efforts to cope with the situation that have been carried out. A cycle analysis program has been produced for calculation of total performance of a wast heat recovery system for a vehicle engine in the previous study. Water has been selected for the working fluid suitable to the purpose of wast heat recovery from engine exhaust gas. This study discusses the development of a cycle analysis program linked with design programs of kernel components of Rankine cycle, i.e., a boiler and a condenser. This program is expected to predict the system cycle performance and characteristics of the components at design stage or in case of design modification.
배석정(Sukjung Bae),허형석(Hyungseok Heo),유한성(Hanseong Yoo) 한국자동차공학회 2015 한국자동차공학회 학술대회 및 전시회 Vol.2015 No.11
A construction equipment such as an excavator wastes about 90% energy out of the fuel. The annual fuel cost of an excavator is comparable to the price of the equipment. Application of a waste heat recovery system on an excavator is attractive and of high return by fuel saving considering the system cost and additional weight. A remarkable feature of the excavator is that the heat source for the waste heat recovery includes the hydraulic fluid in addition to the engine exhaust gas and the engine coolant. It is advantageous to choose a refrigerant in order to recover wast heat at relatively low temperatures. In this study, cycle analysis has been conducted to derive a schematic outline of the system layout and the performance specifications of the core parts of the waste heat recovery system for a 20-ton class excavator. From the cycle analysis, the adequate working fluid has been chosen from the refrigerant group. The cycle analysis has been performed via Refprop 8, which can calculate the properties at any temperature and pressure of refrigerants.
가솔린 엔진용 배기 폐열 회수 시스템의 작동 유체 선정
배석정(Sukjung Bae),허형석(Hyungseok Heo),이헌균(Heonkyun Lee),정영대(Youngdae Choung),황재순(Jaesoon Hwang),이춘범(Chunbeom Lee) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11
Waste heat recovery from exhaust gas of vehicle engine is one of the most effective technology to enhance the fuel energy efficiency. There are a variety of working fluids in the stationary waste heat recovery system of industrial field. However, the investigations for the waste heat recovery of vehicle engine are now forthcoming, in which the engine load of a vehicle varies with time and environmental conditions. This study focuses to select the working fluid for an exhaust waste heat recovery system of a gasoline engine regarding to maximization of cycle efficiency on exhaust conditions. To calculate the cycle performance and thermodynamic properties more efficiently, we produced a cycle analysis program via Refprop 8.