http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
고선호(S.H. Ko),최학규(H.K. Choi),이희범(H.B. Lee),이신형(S.H. Rhee) 한국전산유체공학회 2015 한국전산유체공학회지 Vol.20 No.3
A fishway is a structure on or around artificial and natural barriers, such as dams, locks and waterfalls, to help fishes natural migration. In this paper, a computational fluid dynamics (CFD) code, termed SNUFOAM is used to analyze vertical hydraulic characteristic of rollway of fishway. Volume-of-fluid (VOF) method was used to handle free-surface. It is important to determine the factors influencing flow characteristics in fishway because fish use directional information from the flow characteristics to navigate through fishway. Fishway was modeled in 2-D and the influence of the stream velocity, slope, and weir height of fishway was tested. In results, the transition Reynolds number was 2×10<SUP>5</SUP> ~ 3×10<SUP>5</SUP>.
자유수면의 경계면에서 해의 번짐을 줄이기 위한 경계면 압축 기법 및 주상체에의 적용
이희범(H. Lee),이신형(S. H. Rhee),김동진(D. J. Kim),김선영(S. Y. Kim),박선호(S. Park) 한국전산유체공학회 2014 한국전산유체공학회 학술대회논문집 Vol.2014 No.5
A high speed planing hull is mostly supported by hydrodynamic lift force rather than buoyancy force. The lift force directly influences the running attitude of the planing hull such as trim and sinkage. And the pressure distribution is strongly related to the solution of a free-surface flow around a planing hull. To handle free-surface flow volume-of-fluid (VOF) method have been widely used even it has a disadvantages of interface smearing. In the present study, a new dynamic interface compression method were introduced to reduce interface smearing and avoid unphysical solution. The dynamic compression consists of a function of angle of the flow direction and free-surface. The method was implemented and validated by prismatic body problem.
박선호(S.H. Park),이신형(S.H. Rhee) 한국전산유체공학회 2012 한국전산유체공학회 학술대회논문집 Vol.2012 No.5
Cavitation erosion can be observed on hydraulic mechanical devices and has long been studied, yet a difficult research subject for many years. In the present study, the practical formula to predict the cavitation erosion was developed, and the CFD analyses were performed to determine the cavitation erosion coefficient. Cavitating flows were studied using an Reynolds-averaged Navier-Stokes solver based on a cell-centered finite volume method. To verify and validate cavitating flows, sheet, cloud and super cavitating flows were simulated and compared against existing experimental data. Through the simulations, the computational methods were studied carefully and the simulation of cavitating flows was validated. The cavity length and surface pressure distribution were compared with experimental data and analytic solutions. To develop the cavitation erosion coefficient, cavitating flows in a converging and diverging nozzle and around a hydrofoil were simulated. Cavitation erosion extents were studied for various cavitating flow conditions including various cavitation and Reynolds numbers. By comparison with, existing experimental data, a practical equation for the prediction of cavitation erosion, which is a function of the cavitation number, was developed. The developed practical formula helps predict cavitation erosion observed on the blades of pumps, turbines, and marine propellers.
조류발전용 수평축터빈의 단독성능 평가를 위한 수치 해석법
이주현(J.H. Lee),김동환(D.J. Kim),이신형(S.H. Rhee),김문찬(M.C. Kim),현범수(B.S. Hyun),남종호(J.H. Nam) 한국전산유체공학회 2010 한국전산유체공학회 학술대회논문집 Vol.2010 No.5
Recently, due to high oil prices and environmental pollution issues, interest of alternative energy development increases and the related research is widely conducted. Among those research activities, the tidal stream power generation utilizes the tidal flow as its mechanical power resource and less depends on the environmental condition for installation and operation than other renewable energy resources. Therefore the amount of power generated is quite consistent and straightforward to predict. However, research on the tidal stream energy conversion turbine is rarely found. In the present study, two numerical methods were developed and compared for the open water Momentum Theory, which is widely used for wind turbines, was adopted. The moving reference frame method for Computational Fluid Dynamis solver were also used. Hybrid meshing was used for the complex geometry of turbines. The analysis results using each method were compared to figure out a better method for the performance prediction.