NaC1 수용액과 실리콘 오일에 의한 성층유체의 저온거동에 관한 실험적 연구

장원택,전승배,김병철 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1

To study the influence of phase change of solution and fluid flow on low temperature in thermal storage, solar pond and removal of oil pollution at the sea, an experimental study was carried out in the square cavity filled with stratified fluids of silicone oil and aqueous sodium chloride. In the case of the lower cooling surface, the temperature of the system was dominated by conduction owing to the temperature and concentration fields stabilized by gravity. Liquid superheat influenced less in the lower part and the maximum density of sodium chloride became lower as the salt concentration got higher in the upper part. And the lower the initial temperature in the system the lower the temperature distributions were. When the actual liquid temperature was lower than the liquidus temperature with Ci = 15%, a supercooling phenomenon was observed But with Ci = 5% and Ci = 10% the actual liquid temperature was higher than the liquidus temperature and the temperature of upper fluid also got lower when the concentration of sodium chloride became lower. The influence of latent heat was less in the lower part and the raising ratio in temperature was higher when the initial concentration was lower in the upper part.

축전식 탈염(CDI) 공정의 산업적 전망

소용신,장원택,이윤석,정몽규 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.1

축전식 탈염기술은 에너지 절감형 탈염기술로 최근 연구결과물이 급증하는 추세에 있다. 초기에는 전극 소재개발이 주관심 분야였으나 소규모 제품화 단계에서 적층기술, 이온교환막 응용기술, 스택화 기술을 주로 개발해 왔다. 현재는 소규모 연수기나 정수기 규모로 개발하고 있으나 10,000 ㎥/일 규모의 공정수나 50,000 ㎥/일 규모 이상의 기수 담수화 적용을 위해서는 모듈의 대용량화, 대용량 전력 공급장치개발, 운전 기술 및 제어기술의 확보가 필요한 실정이다. 발전용수 등에서 요구되는 초순수 수질은 전기전도도로써 0.1~0.2 μS/cm 수준이다.

경사진 육면체에서 태양열에 의한 증발 현상에 관한 연구

김병철,장원택,윤재원,박준성 朝鮮大學校 機械技術硏究所 2006 機械技術硏究 Vol.9 No.1

Four solar stills that were fabricated each with cubes and glazing tilted angles of 15°, 30°, 45°, 60°, were compared with the quantities of condensed water. The quantities of condensed water were analysed with the weather conditions and temperatures for three months, On fine days, the quantity of average condensed water was more similar to those of 15° and 30°than to those of 45° and 60°, The quantity of condensed water produced by those of 45° and 60° were very irregular compared to those of 15° and 30", On rainy days, the quantity of condensed water was the most in that of 30° than those of the other angles and in cloudy, rainy and sunny conditions, the condensation quantity was the largest in that of 60°.

냉각면이 있는 정방형내 이종유체의 저온거동에 관한 실험적 연구

전승배,장원택,김병철 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1

Two stratified fluids (water and spindle oil) in aspect ratio of 1 to 1 were studied experimentally with the variation of an initial temperature and a cooling surface temperature in the square cavity with a lower cooling surface. With the initial temperature being varied, a cooling surface temperature were varied. With supercooling phenomenon being processed, a latent heat was emitted. The temperature of the spindle oil was increased with the occurrence of the latent heat. In case of initial temperature was low. the supercooling phenomena were observed and continued up to the end of experimental.

수직 냉각면이 있는 정방형내 성층유체의 열적거동에 관한 실험적 연구

정현철,윤재원,장원택,전승배,이동석,김병철 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1

This study was investigated by experimentals on the thermal behavior of stratified fluids in the square cavity with the vertical cooling surface by variation of initial temperature and cooling surface temperature and concluded as follows: 1. When the cooling surface temperature of the square cavity was -4℃. the supercooling phenomena was occurred every times regardless initial temperature of fluids and when -6℃ freezing was begun with out supercooling phenomena. 2. The higher the initial temperature was, the longer supercooling phenomena duration was, and the longer the supercooling phnomena was, the higher the temperature of the upper fluids was. 3. When the supercooling phenomena of water was occurred, the rate of temperature decrease of silicon oil was higher and when there was no supercooling phenomena, it was almost same the rate of temperature decrease.

장방형내 저온 단일 수평 원관 주위의 동결현상에 관한 실험적 연구

정현철,윤재원,장원택,전승배,이동석,김병철 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1

An experimental study on water in a rectangular cavity with a horizontal cooling tube was carried out to investigate the flow character and thermal behavior in the system. Each experiment was performed with variation of initial temperature and cooling tube temperature. When the cooling tube temperature was -4℃, the supercooling phenomenon was observed regardless of the initial water temperature. And the case of cooling tube temperature was -6℃ with initial temperature was below 4℃, the supercooling phenomenon was also observedin the large region of the test section. When the cooling tube temperature was -10℃, the local region of supercooling phenomenon was observed during the freezing process. And the higher initial temperature was, the higher supercooling degree and the less difference of the ice thickness between upward and downward was observed. It is shown that by controllingthe supercooling phenomena and the cooling tube temperature, it would lead to an increase efficiency of ice making.

수직 원호 용접을 위한 메커니즘 구현에 관한 연구

노태양(Tae-yang Noh),장원택(Won-tek Jang),김재권(Jaek-won Kim),박종연(Jong-yoen Park) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11

One of the primary concerns for welding device design is how to reduce the distance error between welding path and a torch, especially in case that the path is composed of circular and linear combination. This study deals with a mechanism in order to reduce the tracking error at the tangent area of circular and linear path. A portable welding device, called a carriage, has designed for a specific welding path through the comparison of distance error deviation. The welding carriage for a vertical cover plate welding consists of a set of rail, a welding torch and carriage body itself.

수직 원호 용접을 위한 메커니즘 구현에 관한 연구

노태양(Tae Yang Noh),장원택(Won Tek Jang),김재권(Jae Kwon Kim),박종연(Jong Yoen Park) 대한기계학회 2011 大韓機械學會論文集A Vol.35 No.11

용접 장치 설계 시 고려해야 할 중요한 요소 중의 하나는 용접 궤적과 토치의 간격 오차를 줄이는 것이다. 특히 원호와 직선이 결합된 용접 궤적의 경우는 변곡점에서 오차의 영향이 크게 작용한다. 본 연구의 대상은 선체 블록 내부 탱크와 탱크 사이의 유체(물, 기름 등) 이동을 방지하기 위하여 설치되는 커버플레이트(Cover Plate) 용접으로서, 커버플레이트 원호용접은 위보기, 수직, 아래보기의 3 가지 자세를 동시에 포함한다. 본 연구는 작업 궤적의 각 구간 사이에서 발생하는 토치의 궤적 오차를 최소화할 수 있는 2 축 소형 용접 장치 개발에 관한 것으로서, 원호와 직선 부 사이의 변곡점에서 발생하는 토치 궤적 오차를 최소화하기 위한 구동 메커니즘 도출 과정에 대하여 기술하였다. One of the primary concerns in the design of welding devices is how to reduce the distance error between the welding path and the torch, especially when the path has a combination of circular and linear parts. This study investigated a mechanism for reducing the tracking error in the tangent area of a circular and linear path. A portable welding device, called a carriage, has been designed for a specific welding path by considering the distance error deviation. This welding carriage for vertical cover plate welding consists of a rail, a welding torch and the carriage body itself.

경사진 육면체에서 태양열에 의한 증발현상

김병철(Byung-Chul Kim),장원택(Won-Taek Chang),박준성(Jun-Sung Park),윤재원(Jae-Won Yoon) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.9

Solar still was fabricated with glazing titled angles of 15°, 30°, 45°, 60°, water bath and hose for the water feeding and drain. All the data was analysed with weather condition and temperature of the day. In fine days the quantity of average condensed water was almost same between 15° and 30°, which was larger than those of 45° and 60°. The quantity of condensed water produced by those of 45° and 60° were very irregular compared with those of 15° and 30°. In the rainy the quantity of condensation water was the largest for that of ; 30° than those of other angles. In cloudy days and rain with sunny days, the condensation quantity was the largest for those of 60°.