• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.368-373
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• 2001

A major concern on high-energy centrifugal pump is the potential for interaction of two-phase flow phenomena with mechanical response of the pumping elements. The other concern is the pressure pulsations created from trailing edge of the impeller blade and flow separation and recirculation at partial load in centrifugal pumps. These interactions generating between rotor and casing cause dynamic pulsation on pump and exciting pipeline vibration. The higher severity responses, the more lead to failure of pump and system components. Finally, it cause severe axial vibration of single stage pump due to the hydraulic instability in flow condition below BEP.

• 한국항공운항학회지
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• 제23권4호
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• pp.36-41
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• 2015

The cyclone separator is a simple device, which causes the centrifugal separation of materials such as droplets or particles in a fluid stream. The cyclone separator utilizes the energy obtained from fluid pressure and linear motion to create rotational fluid motion. This rotational motion leads the materials suspended in the fluid to separate from the fluid quickly due to the centrifugal force. The rotation is produced by the tangential or involuted introduction of fluid into the vessel. These materials may be droplets of fuel in blow-by gas through an engine. Droplets suspended in the feed liquid may separate according to size, shape, or density. And the change of part dimension in a cyclone separator can yield the its performance variation. The current study shows the influence of design parameters on the performance of a cyclone separator for blow-by gas.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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• pp.259-266
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• 2004

Developed is a sludge treatment system for introducing the waste water mixture with paint sludge from the water bath of paint booth and for recycling cleaned water to paint booth after sludge separation. Floated sludge is introduced from the water surface in the bath by using floating skimmer, and is conveyed by pump to the centrifugal separator where sludge and cleaned water are separated. From the operation results of the present sludge treatment systems applied in actual paint booths, paint sludge can be separated automatically and effectively from water bath with its water content of $60-70\%$, and sludge-free clean water is returned to paint booth.

• International Journal of Fluid Machinery and Systems
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• 제9권1호
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• pp.95-106
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• 2016

A method of optimization design for the blade profile of a centrifugal impeller by controlling velocity distribution is presented, and a plenum fan is successfully designed. This method is based on the inner flow calculation inside the centrifugal impeller, and is related to the distribution of relative velocity. The results show that after optimization, the boundary layer separation on the suction surface has been inhibited and the stability of plenum fan is improved. The flow at the impeller outlet is also studied, and the jet-wake pattern at the impeller outlet is improved obviously by optimization. The calculation result shows that the static pressure and static pressure efficiency can be increased by 15.4% and 21.4% respectively.

• 대한기계학회논문집B
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• 제37권5호
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• pp.531-538
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• 2013

원심압축기에서 볼류트는 임펠러와 디퓨저를 통해 나온 유동을 모아주는 역할을 한다. 압축기의 운전점에 따라 볼류트 내부 발생하는 와류의 세기나 패턴이 달라진다. 압축기 설부에서는 압축기의 운전점에 따라 재유입 유동의 특성이 변화하고, 이러한 특성은 압축기의 성능 및 탈설계점에서의 특성을 이해하는데 중요한 역할을 한다. 본 연구에서는 PIV를 이용하여 압축기의 운전점에 따라 볼류트 내부에 발생하는 스크롤 와류를 측정하였으며, 압축기 설부 근처에서 유동장을 측정한 결과 유량계수가 감소할수록, 설부 측에 발생하는 박리영역이 줄어들고 압축기로 재유입되는 유동이 커지는 것을 알 수 있다.

• 한국염색가공학회지
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• 제35권4호
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• pp.239-245
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• 2023

Cellulose is an abundant biodegradable material in nature with excellent properties, but due to its poor processability, it has been widely studied for processing through modification. Cellulose acetate propionate (CAP) is a cellulose derivative in which the hydroxyl group of cellulose is replaced by acetyl and propionyl groups. CAP has several advantages, such as excellent solubility, structural stability, light and weather resistance, and good transparency. Porous nanofibers with excellent specific surface area, which can be applied in various fields, can be easily formed by the phase separation method using highly volatile solvents. High speed centrifugal spinning is a nano/micro fiber preparation method with advantages such as fast spinning and easy alignment control. In this study, a CAP/polybutylene succinate (PBS) spinning solution with chloroform as solvent was prepared to prepare porous microfibers and the fiber morphology was examined as a function of the disk rotation speed in an high speed centrifugal spinning device.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2002년도 춘계학술대회 논문집
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• pp.301-302
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• 2002

Virtual cyclones have been the subject of aerosol separation studies since they were first developed by Torczynski and Rader (1996). In the virtual cyclone (originally referred to as the anticyclone), the main particle-laden flow follows a wall that curves away from the original flow direction rather than curving into the original direction, as in a cyclone. Although a wall forms the inner boundary of the main flow, its outer boundary is formed by an adjacent flow, often a confined recirculating flow, into which particles are transferred by centrifugal action. (omitted)

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.225-231
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• 1996

The production of recombinant proteins in Escherichia coli often leads to the formation of an intracellular inclusion body. Key process steps that can determine the economics of large-scale protein production from inclusion bodies are fermentation, inclusion body recovery, and protein refolding. Compared with protein refolding and fermentation, inclusion body recovery has received scant research attention. Nevertheless, it can control the final product yield and hence process cost for some products. Optimal separation of inclusion bodies and cell debris can also aid subsequent operations by removing contaminant particulates that foul chromatographic resins and contain antigenic pyrogens. In this review, the properties of inclusion bodies and cellular debris are therefore examined. Attempts to optimise the centrifugal separation of inclusion bodies and debris are also discussed.

• Journal of Microbiology and Biotechnology
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• 제12권3호
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• pp.406-410
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• 2002

A new spin filter consisting of $50{\mu}m$ (nominal pore size) depth fitters rolled on a stainless steel grid was developed, using Saccharomyces cerevisiae as a model suspension cell to evaluate the spin filter performance. In a 1.8-1 fermentor with a rotation speed of 300 rpm and perfusion rate of 4 ml/min, a cell concentration of 49 g/l and ethanol concentration of 45 g/l from 100 g/l glucose could be obtained in a perfusion culture. The major mechanisms for cell separation used by the large-pore spin filter appeared to be centrifugal force and pivotal movement of the cells in the spin filter.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.926-936
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• 1996

Field hulling of high-moisture paddy followed by brown rice drying offers many advantages over the present paddy harvesting and drying offers many advantages over the present paddy harvesting and drying system. We did a preliminary study of the parameters for efficient hulling of high-moisture paddy using the IRRI Centrifugal Huller and two India rice varieties. Hulling capacity , hulling efficiency , brown rice recovery and percent whole bown rice were generally best at the impeller peripheral speed of 44m/s. A second pass through the huller increased hulling capacity , brown rice revery and hulling efficiency, but reduced percent whole brown rice. To solve this , we recommed separation of paddy after hulling and aspiration such that only unhulled and partially -hulled grains will be fed back to the huller. Paddy at even 23% m.c. could be effectively hulled by the impeller-type huller , but the results were generally better at 14 to 17% m.c. Only in percent whole brown rice did the 17 to 23% m.c. range performed better than that of 14% m.c. Difference invarietal response to hulling was observed.