• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.209-211
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• 2008

In this paper, a segregated finite element program for the analysis of an axisymmetric steady flow has been developed in order to investigate the flow inside an annular pipe with a periodic obstacle. For the verification of the developed code, a developing pipe flow has been solved and the solution is in a good agreement with the existing results. For the analysis of the flow inside an annular pipe with a periodic obstacle, three types of periodic obstacle are considered. From the present numerical analysis, various physical variables including flow pattern, pressure distribution and residence time are investigated as a preliminary study to the heat transfer analysis of an annular pipe flow with a periodic obstacle.

• 한국항해항만학회지
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• 제29권6호
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• pp.523-528
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• 2005

장애물이 있는 배관속의 점성유동을 다양한 난류모형을 적용하여 해석하였다. 적용한 난류모형은 k-$\epsilon$, k-$\omega$, Spalart-Allmaras, Reynolds stress 이고, 배관내의 격자는 구조격자(structured grid) 이다. 속도벡터, 압력분포 반복계산(iteration)에 의한 잔류치(residual), 양정(dynamic head) 등을 모사하였다. 4개의 난류모형을 배관유동에 적용하였고 상용 프로그램을 사용하여 해석을 수행하였다.

• 한국유체기계학회 논문집
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• 제18권6호
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• pp.57-62
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• 2015

The test of comparing liquid flow calibration system (approved by KOLAS) for accuracy and structure change test was performed in the test bed in order to evaluate the typical characteristics of the electromagnetic flow meters and parshall flume that are generally used in the water discharging facilities. The results of the accuracy comparing test with liquid flow calibration system showed the error of less than 2%. Pharshall plume got error up to -8.3% (low flow) from the flow rate test, but less than 4% from the accumulated flow test because of offset error at high flow rate and low flow rate. Evaluation of structual change test was tested with only parshall flume using structure and it consisted of installation angle (parshall flume and level sensor) and position change. Installation angle, water level sensor angle and position changing test for parshall flume had errors of 3.1%~-9.2%, 0.4%~-5.6% and 0.2%~1.3% respectively. Especially, the error showed the largest increase when the water level sensor measured the point of decreased flow by the structure change. Therefore, error factors (change of straight pipe length, installation of obstacle or effect of foreign substances on water level sensor) that can often occur in the field should be derived and the research for optimized installation method should be carried out continuously.