http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
장석형,박경석 경희대학교 산학협력기술연구원 1999 산학협력기술연구논문집 Vol.5 No.-
In this study, the temperature distribution of the boundary layer for two injection modeling parts are investigated numerically. The parts are assembled by pressure-jointing procedure after ejecting molding, machine. The temperature of the contact surface is simulated during pass through the pre-heating furnace The characteristics of material for the molding parts are examined by heat analysis. After the modeling the design conditions of the furnace are decided and manufactured. As the result of the modeling, the adequate temperature of the contact surface is about 60℃ after heat treatment To maintain the temperature the furnace should control the inside air temperature up to 80℃ and equip air curtain at inlet and outlet for sustain the temperature.
장석형,박경석 慶熙大學校 大學院 1993 高凰論集 Vol.12 No.-
The main goal of development for an automotive spark ignition engine is to reduce emission, fuel consumption rate and increase engine power. But these cause conflecting techanical problems. So an electronic control engine is practically used to solve those problems. In the engine, compression ratio should be improved and multi-valve system and super charger system should be used to improve engine power. In this case, the mixture in combustion chamber easily causes abnormal combustion: autoignition and knocking produced by improving intake pressure and volumetirc efficiency. By continuous abnormal combustion, heat boundary layers break down and heat loss becomes improving. Therefore an electronic control fuel injection system should be used to improve power and the control system which is for keeping optimum combustion condition by sensing abnormal combustion should be selected. In this study, a main goal is to develop a knock sensor for a high power engine. Knock sensor detects cylinder wall vibration and estimates pressure vibration in a combustion chamber, design parameter of knock sensor is determined by these analysed data.
장석형,홍익표,박경석 경희대학교 산학협력기술연구원 1995 산학협력기술연구논문집 Vol.1 No.-
It is widely recognized that exhaust emissions,fuel economy and engine torque are affected by the coolant temperature of the engine, and logic would suggest that a cooling system offering a better compromise of coolant temperature of the engine would improve both overall engine power and economy. Coolant temperature and intake air temperature near cooling parts is measured CAMS(Computer Aided Measuring System) with K-type thermocouple and A/D converter.
스파크 점화기관의 연소 퇴적물 생성에 관한 연구 (Ⅰ)
장석형(S.H.JANG),박경석(K.S.PARK) 한국자동차공학회 1995 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1995 No.6_1
A spark ignition engine was used to correct engine combustion chamber deposit(C.C.D.), intake valve deposit(I.V.D.), and piston top deposit(P.T.D.). In this study, the effect of gasoline additive on I.V.D. was investigated. Compared with base gasoline and additive mixed gasoline showed a remarkable deposit-forming tendency. And an test procedure has been developed employing a 1.5L P.F.I. (port fuel injection) engine on an engine dynamometer.<br/>
고출력 엔진에서 연소실 내의 노킹음에 의한 공진현상 분석
이두곤,장석형,이종호,박경석,전계석,Lee, Du-Gon,Jang, Seok-Hyung,Yi, Chong-Ho,Park, Kyung-Suk,Jun, Kye-Suk 한국음향학회 1992 韓國音響學會誌 Vol.11 No.4
고출력 가솔린 엔진에서 연소실 내의 급격한 압력 변화에 의해 노킹음이 발생되는데 이로 인하여 공진현상이 일어난다. 일반적으로 이러한 공진음은 5KHz 이상에서 발생되고 이 현상에 대한 고출력 가솔린 엔진의 노킹제어 시스템을 설계하는데 매우 중요하다. 본 논문에서는 고출력으로 설계된 엔진에서 사용되는 노킹 제어시스템을 설게하기 위해 연소실에서 발생되는 노킹현상을 이론적으로 분석하여 노킹음의 모드별 공진 주파수를 예측하였다. 또한 스쿠프 알파 엔진과 독일 보슈사의 비공진형 노킹센서를 시용하여 실험을 수행하였고, 그 결과 이론과 실험이 잘 일치함을 알 수 있었다. Cavity resonances are caused by combustion such as the rapid of pressure rise that occurs from knock in high power gasoline engines. These resonances generally occur at frequencies greater than 5KHz. Analysis of these resonances is important for knock control system design in high power gasoline engines. In this paper, in order to design knock control system for the high power gasoline engine, knock phenomena that occur in chamber were analized theoretically and resonance frequencies of knock signals were predicted. Also, experiments were performed using Soupe x-engine and non-resonance type knock sensor of Bosch co. in Germany. In the result, good agreement was obtained between theoretical prediction and experimental observation.
심창열,장석형,박경석 경희대학교 산학협력기술연구원 1996 산학협력기술연구논문집 Vol.2 No.-
The main goal of development for an automotive spark ignition engine is to reduce emission, fuel consumption rate and increase engine power. But these cause conflecting technical problems. In an engine, compression ratio should be improved and multivalve system and super charge system should be used to improve engine power. In this case, the mixture in combustion chamber easily causes abnormal combustion: autoignition and knocking produced by improving intake pressure. Therefore electronic control fuel injection system should be used to improve power and the control system which is made for keeping optimum combustion condition by sensing abnormal combustion should be selected. In this study, a main goal is to develop knock sensor for a high power engine. By selecting spark timing as a parameter causing knock, let an engine knock artificially. Knocking occurrence crank angle, knocking pressure and knocking intensity are measured by a statistical method in which 10 data per 1 crank degree for 120 cycle are selected. Generally, knock sensor detects cylinder wall vibration and estimate pressure vibration in a combustion chamber. So combustion pressure detected by pressure transducer and cylinder wall vibration detected by knock sensor, accelerometer are estimated and the difference of those three signals are analyzed. These three signals are analyzed by frequency analysis method(Fast Fourier Transformation) and compared with theoretical knock mode in the combustion chamber. A design parameter of knock sensor is determined by these analysed data.
스파크 점화기관의 연소실 형상에 따른 공진현상 해석에 관한 연구
박경석,장석형,Park, Gyeong-Seok,Jang, Seok-Hyeong 대한기계학회 2001 大韓機械學會論文集B Vol.25 No.12
Pressure resonance frequency that is caused in the combustion chamber can be interpreted by acoustic analysis. Until now the pressure resonance has been assumed and calculated to a disc type combustion chamber that neglected the combustion chamber height because the knock occurs near the TDC(top dead center). In this research FEM(finite element method) has been used to calculate the pressure resonance frequency inside the experimental engine combustion. The error of the resonance frequency obtained by FEM has decreased about 50% compared to the calculation of Draper's equation. Due to the asymmetry in the shape of the combustion chamber that was neglected in Draper's equation we could find out that a new resonance frequency could be generated. To match the experimental results, the speed of sound that satisfies Draper's equation is selected 13% higher than the value for pent-roof type combustion chamber.
S.I. 기관 밸브시스템에서의 이상연소에 관한 실험적 연구
박경석,한성철,장석형,손성만 경희대학교 산학협력기술연구원 2002 산학협력기술연구논문집 Vol.8 No.-
The suction pressure of an abnormal condition spark ignition engine which has non adjusting intake valves becomes reduced and residual gas increases at a greater rate than under normal combustions. This reduction in suction pressure is caused by the distribution of in equalable air in a cylinder leading to abnormal combustion. If this condition continues, the engine ceases due to an increase in engine heat loss. In this study, we conducted tests to determine the combustion characteristics of a spark ignition engine under both norman and abnormal conditions. The results of this study will establish basic data analysis for developing an automotive diagnosis system by analyzing some of the factors including pressure in the cylinder, output signal of the MAP Sensor and Exhaust gases.