• Journal of Advanced Marine Engineering and Technology
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• 제29권2호
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• pp.177-184
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• 2005

Experimental studies on the characteristics of ice slurry flows in a circular pipe is rare due to the deficiency of conventional measurement techniques. In this report the flow characteristics are quantitatively investigated by the use of PIV technique concerning the Ice Packing Factor(IPF) and the power changes of pump motor It was experimentally verified that the power loss does not increase any more at a certain IPF value.

• 대한기계학회논문집B
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• 제34권8호
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• pp.775-782
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• 2010

본 연구는 대형 석탄 화력 발전소 탈황설비 내 흡수탑의 성능향상을 위하여 Tray 설치 가능성을 검토하기 위한 연구로 전산 유체역학(CFD) 기법을 이용하여 탈황설비 내 흡수탑의 내부유동을 전산해석 하였다. 흡수탑 내의 Gas와 Slurry의 거동에 대한 사실적 묘사를 위해 Euler-Lagrangian 기법을 이용한 전산해석을 수행하였다. 기존 흡수탑 내에 Tray를 설치함에 따라 탈황설비 내에서 Slurry의 체공시간 증가로 인한 펌프동력 절감과 압력강하 증가로 인한 Fan의 소요동력 증가에 대하여 중점적으로 비교 및 고찰하였다. 그 결과 Tray를 설치함에 따라 흡수탑 내에 Slurry의 체공시간과 배기가스의 압력강하가 증가되는 것을 확인할 수 있었다. 체공시간 증가로 인하여 절약된 동력이 압력강하에 의한 동력 소모량 증가보다 더 큰 것으로 확인되었다.

• Journal of Advanced Marine Engineering and Technology
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• 제27권2호
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• pp.272-279
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• 2003

This study aimed to understand the effects of transporting ice slurry Particles through Pipes with branches. The experimental apparatus was constructed as ice slurry mixing tank. vortex pump, manometers for differential pressure measuring. IPF(ice packing factor) measuring instruments and branches as test sections. The experiments were carried out under various conditions. with concentration of water solution ranging between 0∼20wt% and velocity of water solution at the entry ranging between 1.5∼2.5m/s. The differential Pressure and IPF between the pipe entry and exit were measured. and flowing form was checked throughout the experiment. The pressure loss in 3d branches appeared compared with 6d branches so that it was very high. In the pressure loss of the inside and outside of branches. 6d branches was showed the difference. but was agreed in 3d branches The pressure loss according to concentration of water solution, low value appeared at 10wt% in 6d branches, at 20wt% in 3d branches. The pressure loss according to velocity, did not show large difference. The change of IPF at outlet, appeared +15∼-25% in 6d branches and 0∼-20% in 3d branches. The difference of IPF at the inside and outside of branches. appeared 10∼15% in 6d branches and maximum 5% in 3d branches.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.856-860
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• 2000

Liquid ejector is widely used for power plant water pump, marine pump and transportation of solid materials. It has high working confidence and simple configuration. However, It is not easy to know performance degradation of ejectors in field. When the geometry of ejector is complicate, the diagnosis of faults is required more skillful method without disassemble. This paper gives numerical method to predict cause of $45^{\circ}$ slurry suction ejector performance degradation.

• 상하수도학회지
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• 제18권4호
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• pp.486-492
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• 2004

CMP (Chemical mechanical polishing) is inevitable process to overcome $0.2{\mu}m$ wire thickness in semiconductor industry. In this study, effect of pressure to separate used CMP slurry into solid and liquid for recycle and reuse by ultrafiltration was investigated. Also, water quality after the ultrafiltration such as turbidity and TDS was evaluated. The material of membrane used in the study was PVDF. The used CMP contained 0.5% of solid content and then concentrated up to 18% by weight. The used CMP can not be concentrated higher than 18% because of viscosity and abrasion of pump. The tested feed pressures were 22.1, 29.4 and 36.8 psi. The results have shown that operating at 36.8 psi has advantages on operation time and total flux. The specific flux showed some variation at 1 to 15 of concentration factor but no difference after 15 of concentration factor. Mass balance of solid at initial stage of the operation showed some unbalance because of deposition of solid on the membrane, which was main reason to reduce flux. Turbidity was very stable at lower than 0.2NTU for 22.1 and 36.8 psi of feed pressure.

• 대한기계학회논문집B
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• 제36권12호
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• pp.1201-1207
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• 2012

본 연구에서는 15kW 모터로 구동되는 $5m^3$/min의 유량을 고효율로 공급할 수 있는 2엽 비막힘형 수중 펌프의 임펠러를 설계하는 것을 목표로 임펠러 출구 위치 변화($h_I$), 출구 폭($b_2$) 및 허브 프로파일이 펌프 성능에 미치는 영향을 상용 해석용 프로그램 ANSYS CFX를 사용한 전산해석을 통해 수행하였다. 해석 결과, 임펠러 출구 위치 변화($h_I$) 및 출구 폭($b_2$)이 증가하면 양정 및 축동력의 경우는 $h_I$, $b_2$와 함께 지속적으로 증가하지만 효율의 경우는 $h_I$=38 mm, $b_2$=55 mm 까지만 증가하며, 그 이상의 값에서는 일정한 값을 가짐을 보여준다. 그리고 허브 프로파일의 변화는 상대적으로 임펠러 성능에 큰 영향을 미치지는 않는다.

• 한국지반신소재학회논문집
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• 제15권1호
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• pp.71-81
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• 2016

준설토 이송 시 윤활층에 전자기장을 인가하여 이송 동력을 절감하고, 송토량을 증가시키는 연구의 일환으로, 이런 전자기장 장치의 실제 적용성을 검증하고자 실현장 8.5km의 이송거리의 준설현장에 전자기장 장치를 설치하여 그 효과를 검증하였다. 이송 유속에 관계되는 운전 조건 및 토질상태와 유동상태를 모니터링하고, 획득한 데이터를 송토량과 동력 사이의 관계로 정리하여 전자기장 인가 후 약 30%의 동력대비 이송량 증가가 있음을 확인하였고, 이를 통해 전자기장 인가가 준설토 이송 시 동력절감에 효과가 있음을 확인하였다.

• 한국태양에너지학회 논문집
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• 제33권1호
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• pp.66-72
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• 2013

In this study, the thermal conductive characteristics and basic properties of the nine commercial products of bentonite grouts were studied. Six of the nine products for ground heat exchanger systems are imported and others for civil engineering are domestic. The thermal conductivities of all bentonite products are nearly similar among products. The free swell indexes, viscosities and filter losses of the ground heat exchanger grouts are lower than those of the civil engineering ones. These characteristics seem to increase of the fluidity to fill the bentonite slurry to bore-hall perfectly, rather than to prevent underground water penetration. Thus, the mixtures of bentonites and sands are recommended for high thermal conduction grouts.

• 한국지반신소재학회논문집
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• 제13권1호
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• pp.53-61
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• 2014

준설매립지반은 준설토에 의해 매립되어 지반이 매우 연약한 상태이며, 설계시 정확한 지지력을 예측하는 것은 더욱 힘들다. 실제 준설매립지를 대상으로 여러 가지 연약지반처리공법을 설계하고 있지만, 특히 준설토지반의 특성에 기인한 장비진입 즉 표층처리공법 또한 문제점을 안고 있다. 이러한 문제점을 개선하고자 연약지반에서 적용 할 수 있는 평판재하시험장치를 개발하게 되었다. 본 연구에서는 준설매립현장을 대상으로 현장에서 개발된 평판재하시험을 이용하여 현장시험을 실시하였으며, 아울러 콘테스트만의 결과를 가지고 준설토지반의 지지력을 구하는 실험식을 제안하고자 하였다. 대부분 준설매립지반은 매립경과시간에 따라 표면건조층의 두께가 달라지게 되므로 본 연구에서 제안한 실험식이 매우 효과적인 방법이라 판단되며, 향후 준설토 매립지반의 공법설계시 기초자료로 활용될 수 있을 것이다.

• Journal of Biosystems Engineering
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• 제31권3호
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• pp.161-167
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• 2006

The purpose of this study is to find the optimal conditions of PCM slurry manufacturing equipment for saving the marketing cost and keeping the original quality of products. In addition, the characteristics of the movable container for shipping or distributing products is analysed. The major results are as follows. 1. PCM thermal storage system is designed with the conditions of temperature($-5{\sim}10^{\circ}C$), cold chain time(30 minutes), and one time usage(50 liter). This system includes tank, freezer, circulating pump, cycle type heat exchanger, swelling tank, equipment of supplying PCM supplying unit includes cold tank, cycle type heat exchanger, suction unit and control equipments, etc. 2. After ability test of PCM thermal storage system, it shows that the required freezing time of PCM thermal storage system is less than one of the previous system. The reason is that churn (top and bottom) and compulsion circulation are occurred simultaneously and unit cooler type method is better than chiller type method. 3. By the experiment of transportation latent heat container, it is decided that the best container is $K_1$ with latent heat temperature($0{\sim}5^{\circ}C$) and density(0.15%). However, for $K_l\;and\;K_2$, it is necessary more studies on latent heat thermal conditions and conditions of making method.