다중 주기가 엔진 밸브와 시트 인서트의 마모에 미치는 영향

홍재수(Jae Soo Hong),전경진(Keyoung Jin Chun),윤영한(Young Han Youn) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

The minimization of valve and seat insert wear is a critical factor for consideration in the pursuit of engine performance improvement. This work focuses on the different degrees of wear at three different singular test speeds (10㎐, 25㎐ & multi-㎐). In this study, the seat insert's exterior surface temperature was controlled at 350 ℃, the cycle number was 6.0×10? and the test load was1960N. The wear depth was measured before and after the testing using a confocal laser microscope. It was found that higher speeds cause a greater degree of wear than lower speeds under identical test conditions. It is our intention to use an actual vehicle engine to perform a similar test. For that test, we will apply the multi-㎐ test speed, which is a combination of speeds 10㎐ and 25㎐. In the wear mechanism, adhesive wear, shear strain, abrasive wear and surface fatigue wear were observed.

고령자의 어깨관절 근력 불균형에 대한 연구

홍재수(Jae-Soo Hong),전경진(Keyoung-Jin Chun) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.12

This study examined the muscle imbalance in the cases of isokinetic movement of the shoulder joint, targeting elderly. This experiment was divided into the dominant and non-dominant sides and consisted of flexion, extension, abduction, adduction, external rotation, and internal rotation. Regarding the angular velocity, the peak torque was measured on the equal condition of 30, 60, and 120 degree/s. The concentric and eccentric muscular strengths were measured based on each motion. This study showed that concentric movement tended to decrease the peak torque on the dominant and non-dominant sides alike by increasing the angular velocity, whereas an eccentric movement had a tendency to boost the peak torque by increasing the velocity except for the dominant external rotation. The results from the elderly were different from the young, and the non-dominant side tended to have a higher peak torque than the dominant one regardless of the angular velocity. According to the Antagonistic Strength relationships(Concentric) in old-aged, The data from the elderly showed that the ratio of abduction/adduction under concentric contraction ranged from 20 to 31%, which was higher than that reported previously. The elderly showed an imbalanced muscle tendency. This result is expected to be a useful basic guideline for measuring the shoulder function of the old, and consisted rehabilitation equipment and its programs.

학술 논문 : 차량 개발 단계의 친환경설계 프로세스에 대한 연구

권재수 ( Jae Soo Gwon ),이준하 ( Joon Ha Lee ),홍성준 ( Sung Joon Hong ),조희욱 ( Hee Wook Cho ),홍병권 ( Byoeng Kwon Hong ),홍존희 ( John Hee Hong ) 한국전과정평가학회 2011 한국전과정평가학회지 Vol.12 No.1

Recently the environmental regulations require automobile makers not only to set up the open loop resource recycling system by promoting the material recycling and remanufacturing in disposal phase, hut also to apply Eco-design to their products in design phase. Hyundai Motor Group applies DfD(Design for Disassembly) and DfR(Design for Recycling) from conceptual design stage to production stage with the aspect of concurrent engineering. Eco-design guideline helps engineering designers to understand the necessity of Eco-design. The recyclability check sheets that include detailed design ideas classified by the polymer parts enable each designer to verify the product design by oneself. Furthermore, virtual recyclability inspection is performed in the digital product inspection stage which handles the virtual 3D modeling of products. All these activities became the official procedure in product development process. The DOROSY(Design fOr Recycling Optimizing SYstem) which is developed to help designers evaluate and modify their 3D design to generate the redesign alternatives and finally analyze the effect of environmental design change within a short time. Because DOROSY is based in CATIA which is familiar to engineering designers using the parametric designed template, engineering designer can apply the Eco-friendly idea to product design efficiently.

속도와 주행거리 변화에 따른 엔진 밸브와 시트 인서트의 마모 연구

홍재수(Jae Soo Hong),전경진(Keyoung Jin Chun),김재학(Jae Hak Kim),김양수(Yong Su Kim),김덕영(Deog Yeong Kim),임정규(Jeoung Kiu Im) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.5_1

Engine valve and seat insert wear is one of the most important factors affecting engine performance. Due to higher demands on performance and the increasing use of alternative fuel, engine valves and seat inserts are challenged with wear problems of more significant magnitude than in the past. In order to overcome such problems, a simulator has been developed to generate and control high temperatures and various speeds during motion. The wear simulator is considered to be a valid simulation of the engine valve and seat insert wear process with various speeds during engine activity.<br/> This work focuses on the various degrees of wear at three different singular test speeds (10㎐, 25㎐ & multi-㎐) as well astwo different cycle numbers (2.1×10^6 & 6.0×10^6). Throughout all tests performed in this study, the temperature of the outer surface of the seat insert was controlled at 350℃ and the test load was 1960N. It was found that higher speeds(25㎐) cause a greater degree of wear than lower speeds (10㎐) under identical test conditions (temperature, valve displacement, cycle number and test load). Although test cycle numbers were increased three times, the wear depths were not proportionally increased. Wear occurred rapidly in the initial stages of the test and the wear depths increased less significantly with each cycle number. It is shown that the wear depth of the 2.1×10^6 cycle number test at 25㎐ is much larger than that of the 6.0×106 cycle number test at 10Hz in both the valve and seat insert. Therefore, this result shows that speed (㎐) might affect wear to a greater extent than mileage (cycle number) in the valve and seat insert while the engine is running. Adhesive wear, shear strain and abrasive wear could be observed in the wear mechanisms of valves. Furthermore, adhesive wear, surface fatigue wear and abrasive wear could be observed in the wear mechanisms of seat insert.

인체 동작 분석을 위한 관성센서 비교 검증에 관한 연구

홍재수(Jae Soo Hong),전경진(Keyoung Jin Chun),임도형(Dohyung Lim),고주원(JuWon Ko) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.12

This study was conducted to evaluate a depth sensor based Kinect camera which can be utilized to evaluate a subject’s kinetic and kinematic data during motion. To fulfil our purpose, a manufactured dummy, which is an adapted shoulder to make abduction and adduction motion, were used. And seven healthy male adults with no musculoskeletal or nervous system disorders selected to participate in experiments. Dynamic movement of the dummy and humans were induced by shoulder motion of abduction and adduction up to maximum angle of 60˚. The dummy and human’s motion of shoulder were measured simultaneously using ten infrared camera based three-dimensional (3D) motion capture system, two depth sensor based Kinect camera and IMU sensor. In the test results, phase difference between VICON and IMU had no significantly differences for all of the standing anges and showed maximum angle differences of 3.37~6.35˚ in dummy, and 2.27~5.20˚ in human. In the case of VICON and KINECT, the phase differences were shown that no significantly differences and its maximum angle difference were 2.89~4.14˚ in dummy, and 2.94~5.65˚ in human at the standing angle of 0˚, 30˚, 60˚ and 90˚. However, the phase difference of the dual Kinect camera had significantly diffrences of 8.10±0.59˚ in dummy, and 6.46±0.96˚ in human at the standing angle of 45˚. These results showed that the dual Kinect camera could provide measureing accuracy about maximum 9% of error at 0˚, 30 ˚, 60˚ and 90˚, and maximum 14.5% error at 45˚.

고성능 디젤 엔진 밸브 개발을 위한 마모 시험

홍재수(Hong, Jae-Soo),전경진(Chun, Keyoung-Jin),허용정(Huh Yong-Jeong) 한국산학기술학회 2006 한국산학기술학회 학술대회 Vol.- No.-

엔진 밸브와 밸브시트의 마모는 엔진 성능에 영향을 미치는 가장 중요한 요소 중에 하나이다. 엔진 밸브와 밸브시트는 엔진 구동 과정에서 발생하는 고온의 배기가스, 밸브 스프링의 빠른 움직임, 엔진 폭발 과정의 고압, 균일하지 못한 냉각시스템으로 발생하는 실린더 헤드의 뒤틀림이 만들어 내는 극한 환경을 이겨내야 한다. 본 연구에서는 밸브 및 밸브시트의 마모율과 마모 메카니즘을 명확하게 규명하기 위해서 실제 자동차 엔진 내부의 조건인 온도, 밸브와 밸브시트간의 충돌, 스라이딩 등에 관한 것들을 고려하여 밸브 및 밸브시트가 충돌 시험할 수 있는 전용마모 시험기를 사용하였다. 본 연구에 사용된 시편은 현재 실차에 사용되고 있는 밸브와 밸브시트를 사용하였다. 그 종류는 STR35 밸브, STL #6 및 STL #32이다. 밸브시트는 HVS1-2 재질을 사용하였다.

어깨 관절 마커셋 개발을 위한 3D 동작분석

홍재수(Jae-Soo Hong) 한국산학기술학회 2014 한국산학기술학회 학술대회 Vol.- No.-

어깨 관절은 정형학적 차원에서 가동성이 큰 관절이고, 안정성을 유지하기 주변의 근육과 연부조직에 의존하는 특성을 가지고 있다. 본 연구에서는 Vicon Motion Systems Inc. UK 의 NEXUS와 Body Builder를 활용하여 어깨 동작모델을 개발하였다. 동작모델의 변수는 Humeral Head Center(HHC)를 중심으로 한 어깨 관절의 3가지 동작(Flexion-Extension, Abduction-Adduction, Internal-External rotation)에 대한 각도변화 값으로 설정하였다. 본 연구에서 개발한 어깨 동작모델을 구성하는 Segment 개수는 3개, 마커 개수는 총 9개이다. 실제마커는 5개(GCS: 3개, 팔꿈치: 2개)이고, 가상마커 는 4(HHC: 3개, 팔꿈치: 1개)로 구성되었다. 본 연구에서는 개발된 모델을 활용하여 어깨동작의 근육 기여도 분석을 위한 예비실험을 수행하였다. 향후 반복된 실험과 기존 선행연구들과의 비교를 통해 가 상 마커의 위치를 수정하여 어깨동작모델을 최적화할 계획이다.

엔진스피드가 25㎐일 때 사이클 수에 따른 배기밸브와 시트인서트 마모연구

김재학(Jae Hak Kim),전경진(Keyoung Jin Chun),홍재수(Jae Soo Hong),김양수(Yang Soo Kim),윤영한(Young Han Youn),이원식(Won Sik Lee) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

Wear of seating face of exhaust valve and seat insert are important for the performance and reliability of engine. To improve the quality of engine valve and seat insert, the wears of those seating face have to be inspected. A wear test machine of the engine valve and seat insert was used to study them. Test variable was cycle numbers which is a very important factor for wears of the two faces. Cycle numbers tested were 2.0? 0?, 4.0? 0?, 6.0? 0? and 8.0? 0?. Test speed was 25㎐, test temperature was 350℃, load was 1960N and fuel was LPG. Average Rmax of exhaust valve when cycle number is 2.0? 0? was 74.7㎛, and the average Rmax was increased by 1.5㎛/10?cycle. Average Rmax of seat insert when cycle number is 2.0? 0? was 82.9㎛ and the average Rmax was increased by 1.3㎛/10?cycle. Wear mechanisms of the two faces were tribochemical reaction. Reaction product was covered the faces and protected the wears of the two matrixes. O, C, V, Ca and N were observed in the reaction product.

사이클 수 증가에 따른 엔진밸브 및 시트인서트 착좌면 마모

김재희,전경진,홍재수,윤영한,Kim, Jae-Hak,Chun, Keyoung-Jin,Hong, Jae-Soo,Youn, Young-Han 한국자동차공학회 2007 한국 자동차공학회논문집 Vol.15 No.4

This study investigated the wear of the valve and seat insert seating faces. A tester, an exhaust valve and a seat insert were used. Test variables were cycle numbers ($2{\times}10^6,\;4{\times}10^6,\;6{\times}10^6\;and\;8{\times}10^6$) and Hz (10Hz and 25Hz). The other test conditions such as temperature ($350^{\circ}C$), fuel (LPG) and load (1960N) were fixed. The 10Hz tests indicated that the average Rmax of the valve increased at the rate of $7.76{\mu}m/10^6$ cycles starting from $29.42{\mu}m$ at the $2{\times}10^6$ cycles and that of the seat insert increased at the rate of $8.57{\mu}m/10^6$ cycles starting from $34.19{\mu}m$ at the $2{\times}10^6$ cycles. The 25Hz tests indicated that the average Rmax of the valve increased at the rate of $1.58{\mu}m/10^6$ cycles starting from $74.2{\mu}m$ at the $2{\times}10^6$ cycles and that of the seat insert increased at the rate of $1.25{\mu}m/10^6$ cycles starting from $83.95{\mu}m$ at the $2{\times}10^6$ cycles. The tribochemical reaction product covered the two seating faces, preventing the wear of the seating faces. As cycle numbers became greater, the average Rmax of the seating faces became greater, but the increase rate varied significantly depending on the Hz. The wear mechanism of the two faces was investigated through the tribochemical reaction.

디젤엔진 배기밸브와 시트 인서트의 밸브 재질에 따른 마모 및 매칭성 연구

김양수(Yang Soo Kim),전경진(Keyoung Jin Chun),홍재수(Jae Soo Hong),정동택(Dong Teak Chung) Korean Society for Precision Engineering 2008 한국정밀공학회지 Vol.25 No.6