http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
수리구조 개선을 통한 분배수로 균등분배 성능 향상에 관한 연구(II): Pilot plant 실험을 통한 최적화
박노석,김성수,황준식,임재림,김충환,Park, No-Suk,Kim, Seong-Su,Hwang, Jun-Sick,Im, Jae-Rim,Kim, Chung-Hwan 대한상하수도학회 2007 상하수도학회지 Vol.21 No.5
In order to suggest the methodology for improving the equality of flow distribution in a distribution channel, wet tests were carried out for pilot plant which was scaled down to 1/8 of full scale distribution channel being operated in domestic K_water treatment plant. The correlation between various hydraulic variables and their effects on the equality of flow distribution was evaluated through wet tests using pilot plant. From the results of wet tests, the longitudinal baffle with orifices was installed in the distribution channel, the equality of flow distribution was improved on the condition that the Froude number in pilot plant was similar with that in the full scale channel. Also, the opening ratio of the orifices on the longitudinal baffled did not have influence on the performance of the equality of flow distribution when the average flow velocity and Froud number were relatively low (Froude number ${\fallingdotseq} 0.01$). In the other hand, the performance of the equality of flow distribution was improved with increasing the opening ration of on the longitudinal baffle under conditions of relatively high average flow velocity and high Froud number(${\gtrsim}0.1$)
CFD를 이용한 병열 배열형 상향류식 침전지 수리해석에 관한 연구(I) - 침전지 내 유입유량 불균등 영향 조사 -
박노석,김성수,최종웅,성열붕,강문선,Park, No-Suk,Kim, Seong-Su,Choi, Jong-Woong,Sung, Youl-Boong,Kang, Moon-Sun 대한상하수도학회 2013 상하수도학회지 Vol.27 No.4
In order to investigate the influence of feed water inequity on the settling performance for parallel arranged upflow sedimentation basin in domestic G_WTP(Water Treatment Plant), CFD(Computational Fluid Dynamics) simulation were employed and ADV(Acoustic Doppler Velocimeter) measurements were carried out. From the results of both CFD simulations and ADV measurements, the differences among inlet flow rates to each inlet structure make turbulent energy dissipation uneven overall sedimentation basin. Especially local velocities in the near of both side wall were observed over the design overflow rate(74.4 mm/min). Also, it was confirmed that this inequity of inlet flow would exert an serious influence on the turbidity of settled water which is out from 8 troughs. Even though experimental velocities in full scale basin about 20% higher than the simulated, the results of ADV measurement were in good accordance with those of CFD simulations.
The optimal composition of the filter-media for coping with daily flow-rate fluctuation
박노석,Seong-Su Kim,Dong-Hark Park,Sangyoung Park,최승일 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.5
The fluctuation of inlet flow in a water treatment plant can change the filtration rate abruptly and ultimately reduce the filtration performance by leaking the detained particles in filter media. The surface wave, occurring in the intake well by the fluctuation of inlet flow, reaches the filtration process in a very short time (about 10 minutes), which makes it impossible to control the filtration rate stably. In this study the authors evaluated the effect of daily flow-rate fluctuation on the performance of sand filtration process, and the dual media composition was proposed to improve the filtration performance. Comparative column tests were carried out for the various dual media, such as sand and anthracite compositions. From the results of column tests, dual media with the composition of sand 45 cm and anthracite 30 cm is more effective than the single media with sand in filtration process. In addition, irrespective of dual media composition, the managing ability to cope with that fluctuation tends to be weak at the end of allowable filtration duration time.
박노석,Seong-Su Kim,Kwan-Yeop Kim,Sangyoung Park 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.2
This study was conducted to evaluate the ratio of the pressurized flow to the main inlet flow, which has been considered one of the most important parameters for operating the pump diffusion mixer (PDM). Computational fluid dynamics (CFD) simulation was employed to evaluate the conventional operation rule of PDM and to propose a supplementary operating parameter and criterion. Test simulation of CFD was carried out for the 21 cases of flow ratio in a full scale PDM. The values of local velocity gradient were calculated in each case to analyze the simulation results in more detail. A wet test was conducted to verify CFD simulation results, which measures the factual coagulant dispersion distribution at a distance of 5.4 m from deflector. From results of both CFD simulation and wet test, the flow ratio was adequate as an operating parameter or criterion; also, the velocity ratio (dimensionless) of the pressurized flow to the main inlet was useful in predicting the performance of PDM. In addition, the injected coagulant could be dispersed evenly in overall cross section on the condition that the velocity ratio is at least over 20.
지진에 대한 안전성 평가를 위한 깎기비탈면의 취약도 곡선 작성
박노석,조성은,Park, Noh-Seok,Cho, Sung-Eun 한국지반공학회 2017 한국지반공학회논문집 Vol.33 No.7
지진파로 인하여 발생되는 지진하중은 발생 특성상 예측이 불가능한 불확실성이 존재한다. 또한 비탈면과 같은 지반구조물에는 지반정수의 불확실성이 존재한다. 따라서 이러한 불확실성들을 확률론적 해석으로 고려할 필요가 있다. 본 연구에서는 깎기비탈면에 대하여 확률론적 해석으로 구조물의 안전성을 평가하는 대표적인 방법인 취약도 곡선을 작성하는 방법을 제시하였다. 지반정수의 불확실성을 고려한 취약도 곡선은 Monte Carlo Simulation 기법을 이용해 유사정적 해석으로 작성하였다. 지진파의 불확실성을 고려한 취약도 곡선은 30개의 실제 발생한 지진파로 시간이력해석을 실시하여 Newmark-Type 변위 해석으로 작성하였으며, 취약도 곡선은 최대 우도 추정법을 이용하여 대수정규분포를 갖는 누적 확률분포 함수로 나타내었다. There are uncertainties about the seismic load caused by seismic waves, which cannot be predicted due to the characteristics of the earthquake occurrence. Therefore, it is necessary to consider these uncertainties by probabilistic analysis. In this paper, procedures to develop a fragility curve that is a representative method to evaluate the safety of a structure by stochastic analysis were proposed for cut slopes. Fragility curve that considers uncertainties of soil shear strength parameters was prepared by Monte Carlo Simulation using pseudo static analysis. The fragility curve considering the uncertainty of the input ground motion was developed by performing time-history seismic analysis using selected 30 real ground input motions and the Newmark type displacement evaluation analysis. Fragility curves are represented as the cumulative probability distribution function with lognormal distribution by using the maximum likelihood estimation method.
CFD를 이용한 병열 배열형 상향류식 침전지 수리해석에 관한 연구(II) - 침전지 내 유입유량 균등성 향상을 위한 유입 분배수로 개선 -
박노석,김성수,최종웅,왕창근,Park, No-Suk,Kim, Seong-Su,Choi, Jong-Woong,Wang, Chang-Keun 대한상하수도학회 2014 상하수도학회지 Vol.28 No.2
In order to suggest the methodology for improving the equity of flow distribution in open channel with multiple outlet, CFD simulations were carried out for actual scale distribution channel being operated in domestic G_WTP(Water Treatment Plant). Also, before and after installing the longitudinal multi hole(diameter=250 mm, 116 holes) baffle suggested by this research, turbidity measurements data were collected for evaluating the effects of hydraulic modification for inlet flow equity. From the both results, total turbidity of settled water was lowered by 30 % and equity of flow distribution was improved about 60 % compared with before hydraulic structure modification.