Prof. Van Thinh Nguyen

Education:

  • Ph.D. (Dr.-Ing.) in Hydraulic and Water Resources Engineering at the University of Karlsruhe (KIT), Germany (summa cum laude).
  • Dipl. Math. (MSc. equivalence) at the University of Karlsruhe (KIT), Germany.

Research Areas:

  •  Hydraulic and Water Resources Engineering: Environmental, turbulent, multiphase and stratified flows and transport processes in water bodies (channels, rivers, lakes, estuaries, oceans and aquifers), hydrological processes, nonlinear internal waves.
  • Computational/Environmental Fluid Dynamics for different length scales from micro- to geophysical fluids: Modeling, algorithm development, numerical analysis and applications in environmental, hydraulic and water resources engineering.
  • Computational Sciences: Computational mathematics, code development, data analysis and hydroinformatics, High Performance Computing (HPC), Geographical Information Systems (GIS), Inverse Problems.

 Employment History:

 Academic Experience

  • 09/2016 – present: Assoc. Professor at the Department of Civil and Environmental Engineering, Seoul National University, South Korea.
  • 10/2009 – present: Adjunct Professor at the School of Engineering, University of Guelph, Canada.
  • 01/2009 – present: Founder and Advisory Board of Institute for Computational Science and Technology (ICST), Vietnam.
  • 09/2019 – present: Distinguished Professor at Thuy Loi University, Vietnam.
  • 07/2017 – 08/2018: Visiting Professor at the Department of Civil and Applied Mechanics, McGill University, Canada.
  • 07/2017 – 08/2018: Visiting Professor at the Department of Applied Mathematics, University of Waterloo, Canada.
  • 05/2018 – 08/2018: Visiting Professor at the Department of Civil and Environmental Engineering, UC Davis, USA.
  • 07/2017 – 08/2018: Visiting Professor at the Department of Mathematics and Statistics, University of Guelph, Canada.
  • 08/2011 – 08/2016: Assist. Professor at the Department of Civil and Environmental Engineering, Seoul National University, Korea.
  • 06/2004 – 06/2008: PDF at Department of Applied Mathematics, University of Waterloo, Canada.
  • 03/2003 – 12/2005: PDF at Department of Mathematics and Statistics, University of Guelph, Canada
  • 01/2000 – 12/2002: PDF at the Institute of Hydraulic Engineering and Water Resources Management, University of Karlsruhe, Germany.

Industrial Experience

  • 08/2008 – 05/2010: Software Architect at the Greenland International Consulting Ltd., Canada.
  • 04/1999 – 09/2001: Research engineer at Federal Waterways and Research Institute of Germany

Awards

  •  10/2014: Visiting Fellowship at the Institute for Mathematics and its Applications (IMA), University of Minnesota, USA.
  • 08/2008: Visiting Fellowship at the Fields Institute, University of Toronto, Canada.
  • 06/2006: Visiting Fellowship at the Institute for Mathematics and its Applications (IMA), University of Minnesota, USA University of Minnesota, USA.
  • 2003-2005: NSERC PDF, National Sciences and Engineering Research Council of Canada.
  • 1994-1999: Scholarships of German Academic Exchange Service (DAAD) for PhD. Research.

Publications:

Books:

  • V. Th. Nguyen, “Three Dimensional Computation of Turbulent Flows in Meandering Channels”, University of Karlsruhe, Germany, ISSN 0176-5078 (2000).

Software Developer:

SNU-Watershed Simulation (SNU-WS) Tool (Copyright protection by Korean Government)

 Keynote and Invited Talks (selected from last 5 years)

  •  Keynote speaker at International Conference on Water Resources and Coastal Engineering 2019 (ICWRCE2019), “Numerical Modeling and Its Applications in Water Resources, Hydraulics and Coastal Engineering”, Danang, Vietnam, April 25-26, 2019.
  • Keynote speaker at Seoul International Conference on Engineering and Applied Science (SICEAS), “Turbulence Flows: Modelling and Application in Engineering” Seoul, Korea, February 7-9, 2017.
  • Keynote speaker at the 4th Asia Symposium on Engineering and Information (ASEAI). “Recent Development and Applications of Computational Fluid Dynamics in Civil and Environmental Engineering” Jeju, Korea, April 19-21, 2016.
  • Keynote speaker at Annual Conference of Vietnamese Young Scientists (ACVYS-2016), Application of Computational Fluid Dynamics in Science and Engineering”, Chung-Ang University, Seoul, Korea, May 29, 2016.
  • Keynote speaker at International Conference on Multiphysical Interaction and Environment. “Recent Development and Application of Computational Fluid Dynamics in Water Resources and Environmental Engineering”, Vinh Long Province, Vietnam, March 9-10, 2015.
  • Invited speaker at the Fourth International Conference on Computational Science and Engineering (ICCSE-4), Introduction to an Effective GIS-Based Watershed Simulation Tool. July 24-27, 2019, Ho Chi Minh City, Vietnam.
  • Invited speaker at Department of Civil and Applied Mechanics, McGill University, Canada; “Numerical Modeling and Its Applications in Water Resources, Hydraulic and Environmental Engineering”; Montreal, Canada, April 17, 2018.
  • Invited speaker at International Conference: The VIEW Infrastructure Performance 2017. “Application of Computational Fluid Dynamics for Design, Safety and Maintenance of Hydraulic Structures”, Nov. 11, Seoul, South Korea.
  • Invited speaker at Int. Symposium on Water, Feedbacks and Complexity, Korea University, South Korea; “Turbulent Flows: Modeling and Application in Hydraulic Engineering”, May 30, 2017.
  • Invited speaker at 9th Joint-Symposium between Hokkaido University and Seoul National University,Turbulence Model and Its Application in Hydraulic Engineering”, Nov. 24-25, 2016, Hokkaido University, Japan.
  • Invited speaker at Institute for Advanced Simulation, Juelich Forchungszentrum, Germany. “HPC, an effective tool for three-dimensional simulations of nonlinear internal waves”, Jun. 30, 2016.
  • Invited speaker at Department of Hydraulic Engineering and Water Resources Engineering, University of Kassel, Germany, “Applications of CFD in Hydraulic and Water Resources Engineering”, July 01, 2016.
  • Invited speaker at 4th International Symposium on Advanced Technology for River Management, SNU, Seoul, “SNU-Watershed Modeling Tool”. April 21-23, 2016.
  • Invited speaker at International Symposium on Clean Water on Demand. “Watershed and Water Quality Modeling”, Ho Chi Minh City, Vietnam, Jan. 20, 2016.
  • Invited speaker at the Department of Mathematics and Statistics, University of Guelph, Canada. “Three-dimensional simulation of nonlinear internal waves in the Great Lakes and St. Lawrence Estuary”, Jan. 6, 2015.
  • Invited speaker at the SMART Water Grid International Conference. “Numerical Simulation of Hydrodynamics and Sediment Transport around a Hydraulic Structure on a River”, Seoul, Nov. 25-27, 2014.
  • Invited speaker at IMA Hot Topics Workshop: Impact of Waves along Coastline. “Numerical Simulation of Tidal Elevation along the West Coast of Korea”. Oct. 14-17, 2014, IMA, Minnesota, USA.
  • Invited speaker at 3rd International Symposium on Advanced Technology for River Management. “Numerical simulation of hydrodynamics and bed morphology around Gangjoeng Weir”, SNU, Seoul, Sept. 14-16, 2014.
  • Invited speaker at Civil Engineering Leader’s Network (CELeN), KSCE 2013 Convention, “Civil Engineering and Sustainable Future: “A Contrast between Developed and Developing Countries”, Oct. 2013, Korea.
  • Invited speaker at the 8th International OpenFOAM Workshop, “Applications of OpenFOAM in Hydraulic Engineering”, June 11-14, 2013, Jeju Island, Korea.

Selected Papers Published in Peer-Reviewed Journals:

  1. V.T. Nguyen and M. Lee; “Effect of Open Boundary Conditions and Bottom Roughness on Tidal Modeling around the West Coast of Korea”; Water 2020, 12, 1706, pp. 1-26 (DOI:10.3390/w12061706)
  2. D. N. Khoi, V. T. Nguyen, T. T. Sam and P. T. T. Nhi; “Evaluation on Effects of Climate and Land-Use Changes on Streamflow and Water Quality in the La Buong River Basin, Southern Vietnam”, Sustainability 2019, 11, 7221; pp. 1-15 (DOI:10.3390/su11247221).
  3. V. Th. Nguyen, Th. Ch. Nguyen and J. Nguyen, “Numerical Simulation of Turbulent Flow and Pollutant Dispersion in Urban Street Canyon”, Atmosphere 2019, 10, 683, pp. 1-30. (DOI: 10.3390/atmos10110683).
  4. N. Khoi, V. Th. Nguyen, T. Thao Sam, N. Ky Phung and N. T. Bay, “Responses of river discharge and sediment load to climate change in the transboundary Mekong River Basin”; Water and Environment Journal, 2019, pp. 1-14 (DOI: 10.1111/wej.12534).
  5. V.Th. Nguyen and Minjae Lee, “Effect of Open Boundary Conditions on the Tidal Modelling Around the West Coast of Korea”, Springer Nature Singapore, DOI: 10.1007/978-981-15-0291-0_100.
  6. N. Khoi; T. T. Sam; P. T. T. Nhi; N. T. Quan; B.V. Hung; N. K.Phung; and V.Th. Nguyen; “Uncertainty Assessment for Climate Change Impact on Streamflow and Water Quality in Dong Nai River Basin, Vietnam”, World Environmental and Water Resources Congress 2019, ASCE, pp. 366-373 (May 31, 2019) (DOI:10.1061/9780784482377).
  7. Ng. Anh Triet, Ng. Duc Phuong, V. Th. Nguyen, and C. Nguyen H., “Regularization and Error Estimate for the Poisson Equation with Discrete Data”, Mathematics, 2019, 7(5), 442; pp. 1-20 (DOI:10.3390/math7050422).
  8. H.Q. Nguyen, G. Meon, and V.T. Nguyen, “Development of an Event-Based Water Quality Model for Sparsely Gauged Catchments”, Sustainability 2019, 11, 1773; pp. 1-27 (DOI: 10.3390/su11061773).
  9. T. Sam, D.N. Khoi, N. T. Thao, P. T. Nhi, N.T. Quan, N. X. Hoan, and V.Th. Nguyen, “Impact of climate change on meteorological, hydrological and agricultural droughts in the Lower Mekong River Basin: a case study of the Srepok Basin, Vietnam”, Water and Environmental Journal, (2018) (DOI: 10.1111/wej.12424)
  10. T. Nguyen, V. C. H. Luu, H. L. Nguyen, H. T. Nguyen and V. Th. Nguyen, “Identification of source term for the Rayleigh‐Stokes problem with Gaussian random noise”, Mathematical Methods in the Applied Sciences, Vol. 41 (14), pp. 5593-5601, July, 2018 (DOI/10.1002/mma.5101).
  11. V. Th. Nguyen and Carlos Serrano Moreno, “Numerical Simulation of Sediment Transport and Scouring around Hydraulic Structures on Rivers”. Wold Environmental and Water Resources Congress 2018, ASCE, pp. 263-271 (May 31, 2018) (DOI:10.1061/9780784481424.027).
  12. V. Th. Nguyen and H. H. Nguyen, “Development of a Modeling Tool for Watershed Systems”. World Environmental and Water Resources Congress 2017, ASCE, pp. 373-383 (May 18, 2017) (DOI:10.1061/9780784480601.033).
  13. V. Tran, M. Kirane, H.T. Nguyen and V. Th. Nguyen, “Analysis and Numerical Simulation of the Three-Dimensional Cauchy Problem for Quasi-Linear Eliptic Equations” Journal of Mathematical Analysis and Applications, Vol. 446 (2017), pp. 470-492, Elsevier Ltd. (DOI: 10.1016/j.jmaa.2016.08.045).
  14. H. Tuan, M. Kirane, L.D. Long and V. Th. Nguyen, “On an Inverse Problem for a Fractional Evolution Equation” Evolution Equations and Control Theory, American Institute of Mathematical Sciences. Evolution Equations and Control Theory, Vol. 6, Nr. 1 (2017), pp. 111-134. (DOI:10.3934/eect.2017007).
  15. H. Tuan, L.D. Long, V. Th. Nguyen and Th. Tran “On a Final Value Problem for the Time-Fractional Diffusion Equation with Inhomogeneous Source “Journal of Inverse Problems in Science and Engineering, Taylor & Francis, pp. 1-29. (DOI: 10.1080/17415977.2016.1259316).
  16. Hoi Hyun Choi, V. Th. Nguyen and John Nguyen, “Numerical Investigation of Backward Facing Step over Various Step Angles”. Journal of Procedia Engineering, Vol. 154 (2016), pp. 420-425 (DOI: 10.1016/j.proeng.2016.07.508).
  17. V.Th. Nguyen and Noah Yun, “Numerical Investigation of Sediment Transport and Bedmorphology on a Stretch of Nakdong River”. Journal of Procedia Engineering, Vol. 154 (2016), pp. 550-556 (DOI: 10.1016/j.proeng.2016.07.551).
  18. T. Nguyen, D. L. Le and V. Th. Nguyen, “Regularized solution of an inverse source problem for a time fractional diffusion equation”, Journal of Applied Mathematical Modeling. Vol. 40 (2016), pp. 8244-8264 (DOI: 10.1016/j.apm.2016.04.009).
  19. V. Th. Nguyen, “Three-Dimensional Numerical Simulation of Nonlinear Internal Waves in the St. Lawrence Estuary, Canada”, Journal of Coastal Research, Special Issue No. 75, pp. 902-906, 2016. (DOI 10.2112/SI75-181.1).
  20. T. Nguyen, M. Kirane, D. L. Le and V. Th. Nguyen, “Filter regularization for an inverse parabolic problem in several variables”, Electronic Journal of Differential Equations, Vol. 2016, No. 24, pp 1-13.
  21. T. Nguyen, D.N.D. Hai, D. L. Le, V. Th. Nguyen and M. Kirane, “On a Riesz – Feller space fractional backward diffusion problem with a nonlinear source”, Journal of Computational and Applied Mathematics, Vol 312 (2017), pp. 103-126 (DOI 10.1016/j.cam.2016.01.003).
  22. N. Nguyen, T. C. Nguyen and V. Th. Nguyen. “Numerical Simulation of Wind Flow and Pollution Transport in Urban Street Canyons”, Advanced Science and Technology Letters, Vol. 120, 2015, pp. 770-777. (DOI: 10.14257/astl.2015.120.152).
  23. V. Th. Nguyen, H. T. Nguyen, Th. B. Tran and A. K. Vo, “On an inverse problem in the parabolic equation arising from groundwater pollution problem”, Boundary Value Problem, Springer, 2015:67, 23 pages. (DOI 10.1186/s13661-015-0319-3).
  24. V. Th. Nguyen, “3D Numerical Computation of Free Surface Flows over Hydraulic Structures in Natural Channels and Rivers”, Journal of Applied Mathematical Modeling, Vol. 39 (2015), pp. 6285-6306. (DOI 10.1016/j.apm.2015.01.046).
  25. V. Th. Nguyen, C.S. Moreno and S. Lyu, “Numerical Simulation of Sediment Transport and Bedmorphology around Gangjeong Weir in Nakdong River”, KSCE Journal of Civil Engineering, 19(7), pp. 2291-2297, Springer (DOI 10.1007/s12205-014-1255-y).
  26. Quoc Viet Tran, Huy Tuan Nguyen, V. Th. Nguyen and Duc Trong Dang, “A general filter regularization method to solve the three-dimensional Cauchy problem for inhomogeneous Helmholtz equations: Theory and Numerical Simulation”. Journal of Applied Mathematical Modeling, Vol. 38 (2014), pp. 4460-4479 (DOI 10.1016/j.apm.2014.03.001).
  27. Huy Tuan Nguyen, Quoc Viet Tran and V. Th. Nguyen, “Some remarks on modified Helmholtz equation with inhomogeneous source”. Journal of Applied Mathematical Modeling, Vol. 37 (2013), pp. 793-814 (DOI 10.1016/j.apm.2012.03.014).
  28. V. Th. Nguyen, Lian Zhao and R.G. Zytner, “Three-Dimensional Numerical Model for Soil Vapour Extraction”. Journal of Contaminant Hydrology, Vol. 147 (2013), pp. 82-95 (DOI 10.1016/j.jconhyd.2013.02.008).
  29. Myung Eun Lee, Gunwoo Kim and V.Th. Nguyen, “Effect of local refinement of unstructured grid on the tidal modeling in the south-western coast of Korea”. Journal of Coastal Research, Special Issue No. 65, 2013, (DOI 10.2112/SI65-341.1).
  30. K.G. Lamb and V.Th. Nguyen, “Calculating energy flux in internal solitary waves with an application to reflectance”, Journal of Physical Oceanography 39 (3), 2009, p. 559-580 (DOI 10.1175/2008JPO3882.1).
  31. V. Th. Nguyen, F. Nestmann and H. Scheuerlein, “Three–dimensional computation of turbulent flow in meandering channels and rivers”, Journal of Hydraulic Research (IAHR), 45(5), 2007, p.595-609 (DOI: 10.1080/00221686.2007.9521796)
  32. V. Th. Nguyen and F. Nestmann, “Applications of CFD in hydraulics and river engineering”, International Journal of Computational Fluid Dynamics, Vol. 18(12), 2004, p.165-174 (DOI: 10.1080/10618560310001634186).
  33. V. Th Nguyen, E Morgenroth, HJ Eberl, “A mesoscale model for hydrodynamics in biofilms that takes microscopic flow effects into account”, J. Water Science and Tecchnology (IWA), 52(7), 2005, p. 167-172. (DOI: 10.2166/wst.2005.0197).

Papers in Proceedings (selected from last 6 years):

  1.  V.T. Nguyen, H. H. Nguyen, H.Q. Nguyen, D. N. Khoi; “An Estimation of the Responses of Hydrology and Water Quality to Climate Change for Catchment Scale in Vietnam”, World Environmental and Water Resources Congress 2019, ASCE, May 31, 2019.
  2. Taeyoon Lee and V. Th. Nguyen, “Numerical investigation of the relationship between flow characteristics and DO concentration in a water aeration system”, The 6th International Conference of Euro Asia Civil Engineering Forum, Aug. 22-25, 2017, Seoul, South Korea.
  3. Taeyoon Lee and V. Th. Nguyen, “2D Numerical Simulation of Fine Bubble Flow in Straight Pipes”. The Third Int. Conference on Computational Science and Engineering, Nov. 28-30, 2016, Ho Chi Minh City, Vietnam.
  4. Thanh Chuyen Nguyen, V. Th. Nguyen, “Using Various RANS Models to Evaluate the Impact of Building Roof Shape on the Airflow and Pollution Transport in Street Canyon”, The Third Int. Conference on Computational Science and Engineering, Nov. 28-30, 2016, Ho Chi Minh City, Vietnam.
  5. Hong Ha Nguyen,  V. Th. Nguyen, “SNU Watershed Modelling Tool: A Case Study in Vietnam”, The Third Int. Conference on Computational Science and Engineering, Nov. 28-30, 2016, Ho Chi Minh City, Vietnam.
  6. Nguyen, Thanh C. Nguyen, V. Th. Nguyen, “Effect of architectural roof design and building height on flow field and pollution transport in street canyon”, 2015 Asian Conference on Civil Material and Environmental Sciences, Aug. 25-27, 2015, Osaka, Japan (ISBN 978-986-89298-0-7).
  7. V. Th. Nguyen and Donghae Baek, “3D Numerical Simulation of Turbulent Flow and Pollutant Transport in Meandering Channels”, 22nd Canadian Hydrotechnical Conference, Montreal, Quebec, Canada, April 29 – May 2, 2015.
  8. V. Th. Nguyen and C. Serrano Moreno, “Numerical simulation of sediment transport and bedmorphology around a hydraulic structure on a river”. 11th International Conference on Hydroinformatics. August 17-21, 2014, New York, USA, 8p.
  9. V. Th. Nguyen and Hong Ha Nguyen, “Development of a GIS-based watershed modeling tool”, 11th International Conference on Hydroinformatics. August 17-21, 2014, New York, USA, 8p.
  10. Serrano Moreno, C., and V. Th. Nguyen, “Numerical simulation of sediment transport and scour holes evolution around Gangjeong weir in Nakdong River”. 2nd International Symposium on Advanced Technology for River Management. November 7-9, 2013, Seoul, Korea.
  11. Serrano Moreno, C., and V.Th. Nguyen, 2013: An application of sediment transport model to assess operations of Gangjeon weir in Nakdong River. Smart Water Grid International Conference. November 12-14, 2013, Incheon, Korea.
  12. Serrano Moreno Carlos and V. Th. Nguyen, “Numerical simulation of sediment transport and bedmorphology around Gangjeong weir in Nakdong River”. Korean Society of Civil Engineering 2013 Convention. October 24-25, 2013, Korea.
  13. V.Th. Nguyen, Alexey Matveichev, “3D Numerical Simulation of Turbulent Flows over Hydraulic Structures in Rivers”, 8th International OpenFOAM Workshop, June 11-14, 2013, Jeju, Korea.
  14. V.Th. Nguyen, Alexey Matveichev, “3D Numerical Simulation of Turbulent Flows in Meandering Channels”, 8th International OpenFOAM Workshop, June 11-14, 2013, Jeju, Korea.
  15. V.Th. Nguyen, Alexey Matveichev, “3D Numerical Simulation of Turbulent Flows at Confluence of Channels”, 8th International OpenFOAM Workshop, June 11-14, 2013, Jeju, Korea.
  16. V.Th. Nguyen, Hong Ha Nguyen and Vui Nguyen, “Development of a GIS-based numerical model for watershed and water quality studies” The 10th Int. Conf. on Hydroscience and Engineering (ICHE-2012), Nov. 4 – Nov. 7, Orlando, USA.
  17. V.Th. Nguyen, “3D numerical simulation of nonlinear internal waves in stratified flows” 18th Congress of the Asia and Pacific Division (IAHR-APD2012), August 19-23, 2012; Jeju Island, Korea.
  18. V.Th. Nguyen, Alexey Matveichev, “3D Numerical Simulation of Free Surface Flows over Hydraulic Structures in Open Channels and Rivers”. 18th Congress of the Asia and Pacific Division (IAHR-APD2012), August 19-23, 2012; Jeju Island, Korea.
  19. Myung Eun Lee, Gunwoo Kim and V.Th. Nguyen, “Tidal Modeling of the Yellow Sea using 3D Finite Volume Coastal Ocean Model (FVCOM)”, 2012 Conference of KAOSTS (The Korean Association of Ocean Science and Technology Societies).

Ocean Modeling

 Western Ocean of the Korean Peninsula
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Current Around SW-Coast by M2 Tide
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  • The speed of the tidal current is generally less than 1.6 km/h in the middle of YS, it may increase to more than 5.6 km/h near the coast.
  • The fastest tides reaching 20 km/h occur in the Uldolmok Channel between the Jindo Island and Korean Peninsula.
  • The fastest current provided by numerical results was reaching 3 m/s for M2 in this region.

Numerical Modeling for Stratified Flows, Internal Waves and Mixing Processes in Great Lakes, Estuaries and Oceans

Internal waves (IWs) in stratified flows propagate along the interface separating waters, usually where a layer of warmer water lies over a layer of colder water (although differences in salinity may also give rise to the density difference). In thermally stratified waters the thermocline, where the temperature changes rapidly with depth, separates warmer surface waters from the colder deeper water. IWs represent an important mechanism for mixing surface and deeper water, and for the transport of organisms, sediments and pollutants. The mixing and the vertical displacement of the thermocline associated with IWs play an important role in the stratified flows in lakes, estuaries and oceans. Given the need to understand the processes of IW generation, propagation, and interaction with boundaries, we have carried out some three-dimensional numerical simulations to understand the mechanism of these processes for Lake Erie and St. Lawrence Estuary in Canada.

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Internal Waves Interacting and Shoaling on a Slope
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 Bathymetry of Lake Erie (Great Lakes in Canada)
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 Free Surface Elevation
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Internal Waves

3D Numerical Simulation of Turbulent Flow in Open Channels & Rivers

The flow in rivers, the flow over man-made hydraulic structures such as spillways, weirs, sluices, fluvial works, etc. are very complicated, because they are not only turbulent and highly three-dimensional, but also have irregular boundaries of a natural river bed and complex manmade structures and free surfaces. Among the important physical phenomena characterizing these flows are the generation of secondary currents, flow separation, reattachment and interaction of the flow with movable river boundaries and hydraulic structures. For such flows it is very difficult to accurately calculate the free surface positions, secondary currents and turbulent structures. The secondary currents and turbulent flows play an important role in nautical problems, sediment transports, bed and bank erosions. Thus the ability to accurately predict the three-dimensional flow in rivers, the flow over hydraulic structures, the associated sediment transport and morphological changes is crucial in the practice of hydraulic and river engineering.

1. Turbulent Flows over Hydraulic Structures

1.1 Flow over Weirs

1. Turbulent Flows over Hydraulic Structure

Application: Gangjeong Weir in Nakdong River
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 Turbulent Flow over Kostheim Weir in Main River
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  Turbulent Flow over Lisdorf Flood Gate in Main River
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 Water Surface Evolution at Lisdorf Flood Gate
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RANS Model

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LES Model

1.2 Flow Around a Pier

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 Vorticity: RNG k-ε (Top), Realizable k-ε (Middle), Bottom (LES)

2. Turbulent Flows in Meandering Channels

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Williams River in Alaska
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 Secondary Flows
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3. Turbulent Flows at Confluence of Channels

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Multiphase Flows and Transports in Porous Media: Groundwater Modeling

Multiphase flow and transport of compositionally complex fluids in geologic media is of importance in a number of environmental problems, such as in petroleum reservoir engineering, some of hydrocarbons and other organic chemicals often leaking into the soils and groundwater supplies; many potential groundwater contaminants are introduced at or near the soil surface via atmospheric deposition, spills, leakage from underground tanks, subsurface waste disposal, etc.

Soil Vapor Extraction Modeling

 Non-aqueous phase liquid (NAPL) saturation Sn changed over time
 Concentration of contamination C changed over time

Numerical Simulation of Sediment Transport and Bed morphology

Scour around hydraulic structures is one of critical problems in hydraulic engineering. Under prediction of scour depth can lead to costly failures in the structure, while over prediction can result in unnecessary construction costs. Unfortunately, up-to-date empirical scour methods and equations based on laboratory data are not always able to reproduce field conditions. Because physical scales, fluid properties and boundary conditions in lab-scale models should be derived from a large-scale prototype of field conditions according to the Hydraulic Similitude Laws. However, unlike physical models, computational fluid dynamics (CFD) tools can perform using real field dimensions and operating conditions to predict turbulent flows and sediment scour.

Application: Simulation of Sediment Transport at Gangjeong weir

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 Simulation of River Bed Evolution
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 Evolution of the River Bed After the Weir Gate

GIS-Based Watershed and Water Quality Simulation Tool (SNU-WS)

Typical techniques for determining the extent and magnitude of point and non-point source pollution problems include long-term surface water monitoring and computer-based simulation. Due to the time and expense associated with surface water monitoring, however, computer simulations have been relied upon more frequently to provide needed information for the development and implementation of point and non-point source control programs. A numerical model is conceived as a system for supporting the development of Total Maximum Daily Loads (TMDLs). Developing TMDLs requires a watershed-based approach that integrates both point and non-point sources. An assessment of point and non-point sources is a multipurpose environmental analysis system for use by national, provincial, regional and local authorities/agencies in performing watershed and water quality studies.

Watershed and water quality models are commonly considered an essential tool for evaluating the sources and controls of sediment, nutrient and pathogen loading to surface waters. Such models provide a framework for integrating the data that describe the processes and land-surface characteristics that determine pollutant loads transported to nearby water bodies. The utilization of watershed models, however, is a difficult, tedious task because of the broad spatial and temporal scales that must be considered, as well as the large amount of data that must be compiled, integrated, analyzed and interpreted. GIS (Geographic Information System) technology provides the means for processing, and presenting spatially-referenced model input and output data. Through the use of GIS, the numerical model has the flexibility to display and integrate a wide range of information (e.g., land use, point source discharges, water supply and withdrawals) at a scale chosen by the user. The model will be working under the GIS umbrella, allows users to quickly evaluate selected areas, organize information, and display results.

The numerical tool will take advantage of recent developments in open source software, data management technologies, and computer capabilities to provide the user with a fully comprehensive watershed management tool. The model is designed to facilitate scenarios of Climate Change. The model developed in this study, namely the SNU-WS (Seoul National University WaterShed Simulation) Tool, is a combined hydrologic runoff and river routing model. The model contains three main parts immerged into the open source MapWindow GIS software (www.mapwindow.org) as plugins; the first part is a pre-processing tool; the second part is the runoff calculation tool based on the theory of Generalized Watershed Loading Functions (GWLF) with a number of modifications and enhancements on runoff, sediment yields and daily time step output; and the last part is a routing model engaged with the well-known HEC-RAS model. The model is programming in VB.NET, and designed to complement and interoperate with enterprise and full-featured under MapWindow GIS functions.

An Application for Tri An Region in Vietnam

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