다구찌 기법을 이용한 FCM 가스켓의 강건 설계에 관한 연구

정진은(Chung, Jin-Eun),안중규(Ahn, Jueng-Kyu) 한국산학기술학회 2013 한국산학기술학회논문지 Vol.14 No.7

본 연구에서는 비석면 FCM(Fiber-elastomer Coated Metal) 가스켓의 강건 설계를 수행하였다. 이를 위하여 직교배열표를 사용한 실험계획법에 따라 전단력을 측정하는 실험을 수행하고 다구찌 기법을 사용하여 망대 SN비를 산출하여 영향을 미치는 제어인자를 파악하고 분산 분석을 수행하였다. 전단력에 영향을 미치는 제어인자로 온도, 압 력, 시간 및 습도를 선택하였으며 각 제어인자에 대하여 3수준을 고려하여 L<sub>9</sub(3⁴)> 직교배열표를 작성하였고, 이에 근거하여 측정 실험을 수행하였다. 다구찌 기법을 사용하여 망대 SN비를 산출하고 델타 통계량을 계산하였다. 시간의 델타 통계량이 0.93으로, 시간이 전단력에 가장 큰 영향을 미치는 결과를 얻었다. 다음으로 온도, 압력, 습도 순으로 영향을 미쳤다. 또한 시간 80초, 온도 200 oC, 압력 90 kgf/cm² 습도 60 %RH의 조건에서 전단력이 최대가 됨을 보 였다. 이에 대한 분산 분석을 수행한 결과 시간과 온도는 각각 p값 0.037, 0.098을 보여 신뢰수준 95%와 90%에서 유 의함을 밝혔다. This paper deals with the robust design of the non-asbestos FCM(Fiber-elastomer Coated Metal) gasket. In order to this, the measurement of the shear stress based on the design of experimet using the orthogonal table was carried out and the control factors for shear stress using the larger-the-better SN ratios with the Taguchi method were evaluated. In addition, the analysis of variance for SN ratios was conducted. The temperature, pressure, duration time and humidity were selected as the control factors. The orthogonal table L<sub>9</sub(3⁴)> was made of 3 levels for each factor and the measurement of shear stress was acomplished on the base of the table. Delta statistics of time is the highest value 0.93 and therefore the time affect the largest effect on the shear stress of gasket. Also from the analysis, the shear stress shows maximun at the duration time 80 sec, temeratue 200 oC, pressure 90 kgf/cm2, humidity 60 %RH. P values of duration time and temperature as a results of the analysis of variance are 0.037 and 0.098. Therefore the analysis has significant each with 95% and 90% confidence level.

[디젤엔진] 코히어런트 화염면 모델을 이용한 스트레치 층류 확산 화염의 수치 계산

정진은(Jin-Eun Chung),진영욱(Young-Wook Chin) 한국자동차공학회 1999 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

The transient process being experienced by the 1-D stretched laminar diffusion name initiated at the fuel-oxidizer interface was investigated using the coherent name sheet model. Under the diesel-engine combustion environment the results show that the time to steady state was pretty short compared to the inverse of strain rate, and hence the employment of tabulation of precalculated steady-name results in the calculation of turbulent diffusion names<br/> using the coherent name sheet model is concluded valid. Also upstream temperatures was found to have only a minor effect on the nondimensional name temperature and nondimensional fuel consumption nux even though the latter is sensitive to pressure changes.

[論文] 모델엔진 실린더내의 유동에 대한 다차원 수치해석

정진은(Jin Eun Chung),김응서(Eung Seo Kim) 한국자동차공학회 1989 오토저널 Vol.11 No.3

A multidimensional numerical simulation for flows in an engine with axisymmetric geometry was performed.<br/> Three kinds of differencing schemes, namely, skew upwind differencing scheme (SUDS), interpolated upwind differencing scheme (IUDS), upwind differencing scheme (UDS), are used in a comparative study. Simultaneously, the effects of the artificial dampings and the grids on numerical results are estimated.<br/> Compared with the measurements, the calculations with SUDS and proper artificial damping show very similar qualitative tendency with observed results. But there are some discrepancies due to numerical errors and unclear boundary conditions.

HIL을 이용한 터보과급기 승용 디젤 엔진의 과도 성능 예측

정진은(Jin-Eun Chung),진영욱(Youngwook Jin),정동영(Dong-young Jeong),정재우(Jae-Woo Chung) 한국자동차공학회 2009 한국 자동차공학회논문집 Vol.17 No.5

The transient performance of the passenger diesel engine equipped with the variable geometry turbocharger was simulated using HIL(hardware-in-the-loop) system. The system consists of engine model as software, and the turbocharger test bench as hardware. The engine model is mean value model which is programmed by the Simulink of the Mathworks. The turbocharger test bench is composed of a blower, some sensors, and DAQ boards. A real time simulation is possible since the operating system based on the real time is included. The results show the good response for the transient characteristics. Therefore this HIL system can be used for development of the new turbocharger effectively.

소형 디젤엔진용 가변 과급기 특성에 관한 연구

정진은(Jin-Eun Chung),진영욱(Youngwook Jin),조훈기(Hunki Cho),강우(Woo Kang),정재우(Jae-Woo Chung),강정호(Jeong-Ho Kang) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

A test bench which is consisted of roots blower, air flow meter, driving unit for VGT actuator, transmitters for temperature and pressure, and the rotational speed sensor was developed to evaluate the characteristics of the VGT system. Measurements using VGT of the 2.0 L diesel engine were carried out. The corrected mass flow rate and the pressure ratio for the compressor of the VGT are related directly with the rotational speed, but they are independent of the rack position of the VGT. The pressure ratio and the corrected mass flow rate of the turbine of the VGT are related directly with the rack position of the VGT, but they don't have any relation with the rotational speed. The mechanical efficiency of the VGT is higher than the conventional turbocharger in the wide range. The efficiency of the VGT at the 0.03 ㎏/s of the mass flow rate is 4.36 times as high as that of the conventional turbocharger. These data will be used to develop the new engine equipped with the VGT system.

승용차용 터보과급기의 마찰손실 측정에 관한 연구(Ⅰ)

정진은(Jin Eun Chung),이상운(Sang woon Lee),전세훈(Se Hun Jeon),정재우(Jae Woo Chung),김기용(Ji Young Kim) 한국자동차공학회 2016 한국자동차공학회 지부 학술대회 논문집 Vol.2016 No.5

The turbocharger is essential to realize the engine down-sizing. The engine down-sizing with turbocharging is an effective way to reduce engine consumption and become widespread engine performance over the whole operating range. The turbocharger has a turbo-lag due to mechanical friction losses. Current turbocharger is mostly equipped with oil bearings: two journal bearings and one thrust bearing. In this study, we are focused on the bearing friction and the experimental equipment was made using a drive-motor, load-cell, magnetic coupling, thrust-load device and oil control system. This experimental equipment imitated the mainly three parameter that is rotating speed, oil condition and thrust load. Finally, in this study, we developed the device for measuring friction losses of turbocharger as the influence of rotating speed, thrust load, oil temperature and pressure.

다구찌 기법을 이용한 FCM 가스켓의 강건 설계에 관한 연구

정진은(Jin Eun Chung),안중규(Juengkyu Ahn),양정모(Jeongmo Yang) 한국자동차공학회 2013 한국자동차공학회 지부 학술대회 논문집 Vol.2013 No.5-2

This paper deals with the robust design of the non-asbestos FCM gasket. In order to this, the measurement of the shear based on the design of experiment using the orthogonal table was carried out and the control factors for shear stress using the larger-the-better SN ratios with the Taguchi method were evaluated. In addition, the analysis of variance for SN ratios was conducted. The temperature, pressure, duration time and humidity were selected as the control factors. The orthogonal table L?(3⁴) was made of 3 levels for each factor and the measurement of shear stress was accomplished on the base of the table. Delta statistics of time is the highest value 0.93 and therefore the time affect the largest effect on the shear stress of gasket. Also from the analysis, the shear stress shows maximum at the duration time 80 sec, temperature 200℃, pressure 90kgf/cm2, humidity 60%RH. P values of duration time and temperature as a results of the analysis of variance are 0.037 and 0.098. Therefore the analysis has significant each with 95% and 90% confidence level.

소형 디젤엔진용 전자식 EGR 밸브 특성에 관한 연구

정진은(Jin-Eun Chung),진영욱(Youngwook Jin),강우(Woo Kang),정재우(Jae-Woo Chung),강정호(Jeong-Ho Kang) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.11_1

A test bench which is consisted of blower, heater, air flow meter, driving unit for electric EGR valve, and cooling system for EGR cooler was developed to evaluate the characteristics of the modulated EGR valve. Measurements using EGR valve of the 2.0 L diesel engine were carried out. For this valve, the relation between duty signal and valve lift shows non-linearity and hysteresis phenomenon, and the response time at opening is 84.2 ms. The mass flow rate through the valve is almost zero under 40% duty and is increased according to the duty signal between 40% to 60% duty. For more than 60% duty, the mass flow rate is dependent only the pressure difference. The maximum ratio of the effective area is 0.55. For the over 60% duty the effective area is almost constant and independent of the mass flow rate, but it is decreased as the mass flow rate increases for between 40% and 60% duty. These data will be used to develop the new engine using the modulated EGR and VGT system.

소형 터보과급기 로터의 관성모멘트 측정

정진은(Jin-Eun Chung),전세훈(Se-Hun Jeon),이상운(Sang-Woon Lee) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.3

본 논문은 엔진 다운사이징의 관점에서 널리 사용되는 터보과급기 로터의 관성모멘트 측정에 관한 연구이다. Trifilar 방법을 이용하여 관성모멘트를 측정하기 위한 장치를 설계 제작한 후, 장치를 검증하기 위하여 교정로터의 관성모멘트를 측정하였다. 측정의 변동계수는 0.43%, CAD 도면의 관성모멘트와 비교하여 0.75% 오차를 보여 개발된 측정장치가 로터의 관성모멘트 측정에 적합함을 확인하였다. 소형 터보과급기의 터빈 로터와 압축기 휠 각 2개에 대한 관성모멘트 측정을 수행하여 1.0% 미만의 변동계수를 보여 정밀한 측정이 가능함을 보였다. 그러나 CAD 도면의 관성모멘트와 비교한 오차는 터빈 로터는 2.76%와 1.30%로 양호하였으나, 압축기 휠의 경우 27.6%와 24.4%로 상당히 크게 나타났다. 연구에 사용된 압축기 휠은 질량이 소형으로 상대적으로 공기저항이 크고 정확한 주기 측정의 어려움으로 큰 오차를 보였다. 따라서 터빈 로터와 압축기 휠을 결합한 상태에서 측정한 값에서 터빈 로터의 관성모멘트를 빼는 간접 방법으로 측정을 수행하였다. 이때 압축기 휠의 관성모멘트 측정에서 1.2% 미만의 변동계수를 보이고 오차는 5.68%, 7.88%의 값을 보였다. Measurements of the moment of inertia of a small turbocharger rotor were studied. A measuring device was manufactured using the trifilar method and the moment of inertia of the calibration rotor was measured to verify the device. The coefficient of variation was 0.43% and the error was 0.75%. The results showed that the device is suitable for measuring the moment of inertia of a turbocharger rotor. Next, the moment of inertia for two turbine rotors and compressor wheels was measured. Those for the turbine rotors showed precise and accurate results in that the coefficients were under 1.0% and the errors were under 3.0%. On the other hand, those for the compressor wheel were precise but inaccurate in that the coefficients were under 1.0% and the errors were over 24.4%. Therefore an indirect method for the compressor wheel was suggested. The results showed that the coefficients were under 1.2% and the errors were under 7.88%.

가변형 터보과급기의 맥동 유동 성능 측정 시스템 개발

정진은(Jin Eun Chung),진영욱(Youngwook Jin),조훈기(Hungi-Cho),강우(Woo Kang),정재우(Jae Woo Chung) 한국자동차공학회 2007 한국자동차공학회 지부 학술대회 논문집 Vol.- No.-

A test bench which is consisted of roots blower, pulsator, air flow meter, driving unit for VGT actuator, transmitters for temperature and pressure, and the rotational speed sensor was developed to evaluate the characteristics of the VGT system. Measurements using VGT of the 2.0 L diesel engine were carried out. The corrected mass flow rate and the pressure ratio for the compressor of the VGT are related directly with the rotational speed, but they are independent of the rack position of the VGT. The pressure ratio and the corrected mass flow rate of the turbine of the VGT are related directly with the rack position of the VGT, but they don’t have any relation with the rotational speed. The mechanical efficiency of the VGT is higher than the conventional turbocharger in the wide range. The efficiency at the 0.03 kg/s of the mass flow rate is 4.36 times as high as that of the conventional turbocharger. These data will be used to develop the new engine equipped with the VGT system.