@article{ValeroSchalkoFriedrichetal.2021,
  author    = {Valero, Daniel and Schalko, Isabella and Friedrich, Heide and Abad, Jorge D. and Bung, Daniel Bernhard and Donchyts, Gennadii and Felder, Stefan and Ferreira, Rui M. L. and Hohermuth, Benjamin and Kramer, Matthias and Li, Danxun and Mendes, Luis and Moreno-Rodenas, Antonio and Nones, Michael and Paron, Paolo and Ruiz-Villanueva, Virginia and Wang, Ruo-Qian and Franca, Mario J.},
  title     = {Pathways towards democratization of hydro-environment observations and data},
  series = {Iahr White Paper Series},
  journal   = {Iahr White Paper Series},
  number    = {1},
  publisher = {International Association for Hydro-Environment Engineering and Research (IAHR)},
  pages     = {1 -- 9},
  year      = {2021},
  language  = {en}
}
@article{vonHaefenKrautwaldStolleetal.2022,
  author    = {von H{\"a}fen, Hajo and Krautwald, Clemens and Stolle, Jacob and Bung, Daniel Bernhard and Goseberg, Nils},
  title     = {Overland flow of broken solitary waves over a two-dimensional coastal plane},
  series = {Coastal Engineering},
  volume    = {175},
  journal   = {Coastal Engineering},
  number    = {August},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1872-7379},
  doi       = {10.1016/j.coastaleng.2022.104125},
  pages     = {14 Seiten},
  year      = {2022},
  abstract  = {Landslides, rock falls or related subaerial and subaqueous mass slides can generate devastating impulse waves in adjacent waterbodies. Such waves can occur in lakes and fjords, or due to glacier calving in bays or at steep ocean coastlines. Infrastructure and residential houses along coastlines of those waterbodies are often situated on low elevation terrain, and are potentially at risk from inundation. Impulse waves, running up a uniform slope and generating an overland flow over an initially dry adjacent horizontal plane, represent a frequently found scenario, which needs to be better understood for disaster planning and mitigation. This study presents a novel set of large-scale flume test focusing on solitary waves propagating over a 1:14.5 slope and breaking onto a horizontal section. Examining the characteristics of overland flow, this study gives, for the first time, insight into the fundamental process of overland flow of a broken solitary wave: its shape and celerity, as well as its momentum when wave breaking has taken place beforehand.},
  language  = {en}
}
@article{BungValero2016,
  author    = {Bung, Daniel Bernhard and Valero, Daniel},
  title     = {Optical flow estimation in aerated flows},
  series = {Journal of Hydraulic Research},
  volume    = {54},
  journal   = {Journal of Hydraulic Research},
  number    = {5},
  publisher = {Taylor \& Francis},
  address   = {London},
  doi       = {10.1080/00221686.2016.1173600},
  pages     = {575 -- 580},
  year      = {2016},
  abstract  = {Optical flow estimation is known from Computer Vision where it is used to determine obstacle movements through a sequence of images following an assumption of brightness conservation. This paper presents the first study on application of the optical flow method to aerated stepped spillway flows. For this purpose, the flow is captured with a high-speed camera and illuminated with a synchronized LED light source. The flow velocities, obtained using a basic Horn-Schunck method for estimation of the optical flow coupled with an image pyramid multi-resolution approach for image filtering, compare well with data from intrusive conductivity probe measurements. Application of the Horn-Schunck method yields densely populated flow field data sets with velocity information for every pixel. It is found that the image pyramid approach has the most significant effect on the accuracy compared to other image processing techniques. However, the final results show some dependency on the pixel intensity distribution, with better accuracy found for grey values between 100 and 150.},
  language  = {en}
}
@article{ZhangValeroBungetal.2018,
  author    = {Zhang, G. and Valero, Daniel and Bung, Daniel Bernhard and Chanson, H.},
  title     = {On the estimation of free-surface turbulence using ultrasonic sensors},
  series = {Flow Measurement and Instrumentation},
  volume    = {60},
  journal   = {Flow Measurement and Instrumentation},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0955-5986},
  doi       = {10.1016/j.flowmeasinst.2018.02.009},
  pages     = {171 -- 184},
  year      = {2018},
  abstract  = {Accurate determination of free-surface dynamics has attracted much research attention during the past decade and has important applications in many environmental and water related areas. In this study, the free-surface dynamics in several turbulent flows commonly found in nature were investigated using a synchronised setup consisting of an ultrasonic sensor and a high-speed video camera. Basic sensor capabilities were examined in dry conditions to allow for a better characterisation of the present sensor model. The ultrasonic sensor was found to adequately reproduce free-surface dynamics up to the second order, especially in two-dimensional scenarios with the most energetic modes in the low frequency range. The sensor frequency response was satisfactory in the sub-20 Hz band, and its signal quality may be further improved by low-pass filtering prior to digitisation. The application of the USS to characterise entrapped air in high-velocity flows is also discussed.},
  language  = {en}
}
@article{OertelBung2015,
  author    = {Oertel, Mario and Bung, Daniel Bernhard},
  title     = {Numerische Str{\"o}mungssimulationen von Fließgew{\"a}ssern : Praxisanwendungen und zuk{\"u}nftige Entwicklungen},
  series = {Korrespondenz Wasserwirtschaft : KW},
  volume    = {8},
  journal   = {Korrespondenz Wasserwirtschaft : KW},
  number    = {H. 3},
  publisher = {Gesellschaft zur F{\"o}rderung der Abwassertechnik},
  address   = {Hennef},
  issn      = {1616-430X},
  pages     = {177 -- 182},
  year      = {2015},
  language  = {de}
}
@article{Bung2013,
  author    = {Bung, Daniel Bernhard},
  title     = {Non-intrusive detection of air-water surface roughness in self-aerated chute flows},
  series = {Journal of hydraulic research},
  volume    = {Vol. 51},
  journal   = {Journal of hydraulic research},
  number    = {Iss. 3},
  publisher = {Taylor \& Francis},
  address   = {London},
  issn      = {1814-2079 (E-Journal); 0022-1686 (Print)},
  pages     = {322 -- 329},
  year      = {2013},
  language  = {en}
}
@article{LeandroBungCarvalho2014,
  author    = {Leandro, J. and Bung, Daniel Bernhard and Carvalho, R.},
  title     = {Measuring void fraction and velocity fields of a stepped spillway for skimming flow using non-intrusive methods},
  series = {Experiments in fluids},
  journal   = {Experiments in fluids},
  number    = {55},
  publisher = {Springer Nature},
  address   = {Heidelberg},
  issn      = {0723-4864 (Print) ; 1432-1114 (Online)},
  doi       = {10.1007/s00348-014-1732-6},
  pages     = {Art. 1732},
  year      = {2014},
  language  = {en}
}
@article{Bung2024,
  author    = {Bung, Daniel Bernhard},
  title     = {Kamerabasierte Fließtiefen- und Geschwindigkeitsmessungen},
  series = {Wasserwirtschaft},
  volume    = {114},
  journal   = {Wasserwirtschaft},
  number    = {4},
  publisher = {Springer Vieweg},
  address   = {Wiesbaden},
  issn      = {0043-0978},
  pages     = {47 -- 53},
  year      = {2024},
  abstract  = {In der wasserbaulichen Forschung werden neben klassischen Messinstrumenten zunehmend kamerabasierte Verfahren genutzt. Diese erlauben neben der Bestimmung von Fließgeschwindigkeiten auch die Detektion der freien Wasseroberfl{\"a}che oder zeitliche Vermessung von Kolken. Durch die hohen r{\"a}umlichen und zeitlichen Aufl{\"o}sungen, welche neueste Kamerasensoren liefern, k{\"o}nnen neue Erkenntnisse in turbulenten, komplexen Str{\"o}mungen gewonnen werden. Auch in der Praxis k{\"o}nnen diese Verfahren mit geringem Aufwand wichtige Daten liefern.},
  language  = {de}
}
@article{OertelBung2012,
  author    = {Oertel, Mario and Bung, Daniel Bernhard},
  title     = {Initial stage of two-dimensional dam-break waves: laboratory versus VOF},
  series = {Journal of hydraulic research},
  volume    = {50},
  journal   = {Journal of hydraulic research},
  number    = {1},
  publisher = {Taylor \& Francis},
  address   = {London},
  issn      = {1814-2079 (E-Journal); 0022-1686 (Print)},
  doi       = {10.1080/00221686.2011.639981},
  pages     = {89 -- 97},
  year      = {2012},
  abstract  = {Since several decades, dam-break waves have been of main research interest. Mathematical approaches have been developed by analytical, physical and numerical models within the past 120 years. During the past 10 years, the number of research investigations has increased due to improved measurement techniques as well as significantly increased computer memories and performances. In this context, the present research deals with the initial stage of two-dimensional dam-break waves by comparing physical and numerical model results as well as analytical approaches. High-speed images and resulting particle image velocimetry calculations are thereby compared with the numerical volume-of-fluid (VOF) method, included in the commercial code FLOW-3D. Wave profiles and drag forces on placed obstacles are analysed in detail. Generally, a good agreement between the laboratory and VOF results is found.},
  language  = {en}
}
@article{ErpicumCrookstonBombardellietal.2021,
  author    = {Erpicum, Sebastien and Crookston, Brian M. and Bombardelli, Fabian and Bung, Daniel Bernhard and Felder, Stefan and Mulligan, Sean and Oertel, Mario and Palermo, Michele},
  title     = {Hydraulic structures engineering: An evolving science in a changing world},
  series = {Wires Water},
  volume    = {8},
  journal   = {Wires Water},
  number    = {2},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {2049-1948},
  doi       = {10.1002/wat2.1505},
  year      = {2021},
  language  = {en}
}
@article{OertelBung2021,
  author    = {Oertel, Mario and Bung, Daniel Bernhard},
  title     = {Hochwasserschutz - eine Aufgabe f{\"u}r eine nachhaltige Wasserwirtschaft},
  series = {Wasserwirtschaft},
  volume    = {111},
  journal   = {Wasserwirtschaft},
  number    = {9-10},
  publisher = {Springer Vieweg},
  address   = {Wiesbaden},
  issn      = {0043-0978},
  pages     = {3 -- 19},
  year      = {2021},
  language  = {de}
}
@article{Bung2011,
  author    = {Bung, Daniel Bernhard},
  title     = {Fließcharakteristik und Sauerstoffeintrag bei selbstbel{\"u}fteten Gerinnestr{\"o}mungen auf Kaskaden mit gem{\"a}ßigter Neigung},
  series = {{\"O}sterreichische Wasser- und Abfallwirtschaft},
  volume    = {Vol. 63},
  journal   = {{\"O}sterreichische Wasser- und Abfallwirtschaft},
  number    = {Iss. 3-4},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1613-7566 (E-Journal); 0945-358X (Print)},
  pages     = {76 -- 81},
  year      = {2011},
  language  = {de}
}
@article{Bung2021,
  author    = {Bung, Daniel Bernhard},
  title     = {Extreme flooding in Western Germany: some thoughts on hazards, return periods and risk},
  series = {Hydrolink},
  journal   = {Hydrolink},
  number    = {4},
  publisher = {International Association for Hydro-Environment Engineering and Research (IAHR)},
  address   = {Madrid},
  pages     = {108 -- 113},
  year      = {2021},
  abstract  = {The low-pressure system Bernd involved extreme rainfalls in the Western part of Germany in July 2021, resulting in major floods, severe damages and a tremendous number of casualties. Such extreme events are rare and full flood protection can never be ensured with reasonable financial means. But still, this event must be starting point to reconsider current design concepts. This article aims at sharing some thoughts on potential hazards, the selection of return periods and remaining risk with the focus on Germany.},
  language  = {en}
}
@article{KerpenBungValeroetal.2017,
  author    = {Kerpen, Nils B. and Bung, Daniel Bernhard and Valero, Daniel and Schlurmann, Torsten},
  title     = {Energy dissipation within the wave run-up at stepped revetments},
  series = {Journal of Ocean University of China},
  volume    = {16},
  journal   = {Journal of Ocean University of China},
  number    = {4},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1993-5021},
  doi       = {10.1007/s11802-017-3355-z},
  pages     = {649 -- 654},
  year      = {2017},
  language  = {en}
}
@article{ValeroBungCrookston2018,
  author    = {Valero, Daniel and Bung, Daniel Bernhard and Crookston, B.M.},
  title     = {Energy dissipation of a Type III basin under design and adverse conditions for stepped and smooth spillways},
  series = {Journal of Hydraulic Engineering},
  volume    = {144},
  journal   = {Journal of Hydraulic Engineering},
  number    = {7},
  publisher = {ASCE},
  address   = {Reston, Va.},
  issn      = {0733-9429},
  doi       = {10.1061/(ASCE)HY.1943-7900.0001482},
  year      = {2018},
  abstract  = {New information regarding the influence of a stepped chute on the hydraulic performance of the United States Bureau of Reclamation (Reclamation) Type III hydraulic jump stilling basin is presented for design (steady) and adverse (decreasing tailwater) conditions. Using published experimental data and computational fluid dynamics (CFD) models, this paper presents a detailed comparison between smooth-chute and stepped-chute configurations for chute slopes of 0.8H:1V and 4H:1V and Froude numbers (F) ranging from 3.1 to 9.5 for a Type III basin designed for F = 8. For both stepped and smooth chutes, the relative role of each basin element was quantified, up to the most hydraulic extreme case of jump sweep-out. It was found that, relative to a smooth chute, the turbulence generated by a stepped chute causes a higher maximum velocity decay within the stilling basin, which represents an enhancement of the Type III basin's performance but also a change in the relative role of the basin elements. Results provide insight into the ability of the CFD models [unsteady Reynolds-averaged Navier-Stokes (RANS) equations with renormalization group (RNG) k-ϵ turbulence model and volume-of-fluid (VOF) for free surface tracking] to predict the transient basin flow structure and velocity profiles. Type III basins can perform adequately with a stepped chute despite the effects steps have on the relative role of each basin element. It is concluded that the classic Type III basin design, based upon methodology by reclamation specific to smooth chutes, can be hydraulically improved for the case of stepped chutes for design and adverse flow conditions using the information presented herein.},
  language  = {en}
}
@article{ValeroBung2016,
  author    = {Valero, Daniel and Bung, Daniel Bernhard},
  title     = {Development of the interfacial air layer in the non-aerated region of high-velocity spillway flows: Instabilities growth, entrapped air and influence on the self-aeration onset},
  series = {International Journal of Multiphase Flow},
  volume    = {84},
  journal   = {International Journal of Multiphase Flow},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0301-9322},
  doi       = {10.1016/j.ijmultiphaseflow.2016.04.012},
  pages     = {66 -- 74},
  year      = {2016},
  abstract  = {Self-aeration is traditionally explained by the water turbulent boundary layer outer edge intersection with the free surface. This paper presents a discussion on the commonly accepted hypothesis behind the computation of the critical point of self-aeration in spillway flows and a new formulation is proposed based on the existence of a developing air flow over the free surface. Upstream of the inception point of self-aeration, some surface roughening has been often reported in previous studies which consequently implies some entrapped air transport and air-water flows coupling. Such air flow is proven in this study by presenting measured air velocities and computing the air boundary layer thickness for a 1V:2H smooth chute flow. Additionally, the growth rate of free surface waves has been analysed by means of Ultrasonic Sensors measurements, obtaining also the entrapped air concentration. High-speed camera imaging has been used for qualitative study of the flow perturbations.},
  language  = {en}
}
@article{Bung2011,
  author    = {Bung, Daniel Bernhard},
  title     = {Developing flow in skimming flow regime on embankment stepped spillways},
  series = {Journal of hydraulic research},
  volume    = {Vol. 49},
  journal   = {Journal of hydraulic research},
  number    = {Iss. 5},
  publisher = {Taylor \& Francis},
  address   = {London},
  issn      = {1814-2079 (E-Journal); 0022-1686 (Print)},
  pages     = {639 -- 648},
  year      = {2011},
  language  = {en}
}
@article{ValeroBungCrookston2019,
  author    = {Valero, D. and Bung, Daniel Bernhard and Crookston, B. M.},
  title     = {Closure to "Energy Dissipation of a Type III Basin under Design and Adverse Conditions for Stepped and Smooth Spillways"},
  series = {Journal of Hydraulic Engineering},
  volume    = {146},
  journal   = {Journal of Hydraulic Engineering},
  number    = {2},
  publisher = {ASCE},
  address   = {Reston, Va.},
  doi       = {10.1061/(ASCE)HY.1943-7900.0001669},
  year      = {2019},
  language  = {en}
}
@article{ValeroBung2017,
  author    = {Valero, Daniel and Bung, Daniel Bernhard},
  title     = {Artificial Neural Networks and pattern recognition for air-water flow velocity estimation using a single-tip optical fibre probe},
  series = {Journal of Hydro-environment Research},
  volume    = {19},
  journal   = {Journal of Hydro-environment Research},
  number    = {3},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1570-6443},
  doi       = {10.1016/j.jher.2017.08.004},
  pages     = {150 -- 159},
  year      = {2017},
  language  = {en}
}
@article{LopesLeandroCarvalhoetal.2017,
  author    = {Lopes, Pedro and Leandro, Jorge and Carvalho, Rita F. and Bung, Daniel Bernhard},
  title     = {Alternating skimming flow over a stepped spillway},
  series = {Environmental Fluid Mechanics},
  volume    = {17},
  journal   = {Environmental Fluid Mechanics},
  number    = {2},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1573-1510},
  doi       = {10.1007/s10652-016-9484-x},
  pages     = {303 -- 322},
  year      = {2017},
  language  = {en}
}
@article{BungErpicumTullis2020,
  author    = {Bung, Daniel Bernhard and Erpicum, S{\´e}bastien and Tullis, Blanke P.},
  title     = {Advances in hydraulic structures engineering},
  series = {Journal of Hydraulic Engineering},
  volume    = {147},
  journal   = {Journal of Hydraulic Engineering},
  number    = {1},
  publisher = {ASCE},
  address   = {Reston, Va.},
  issn      = {0733-9429 (Druckausgabe)},
  doi       = {10.1061/(ASCE)HY.1943-7900.0001851},
  pages     = {1 Seite},
  year      = {2020},
  language  = {en}
}