@inproceedings{ValeroBungCrookstonetal.2016,
  author    = {Valero, Daniel and Bung, Daniel Bernhard and Crookston, B. M. and Matos, J.},
  title     = {Numerical investigation of USBR type III stilling basin performance downstream of smooth and stepped spillways},
  series = {Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016},
  booktitle = {Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016},
  editor    = {Crookston, B. and Tullis, B.},
  isbn      = {978-1-884575-75-4},
  doi       = {10.15142/T340628160853},
  pages     = {635 -- 646},
  year      = {2016},
  language  = {en}
}
@inproceedings{BungValero2016,
  author    = {Bung, Daniel Bernhard and Valero, Daniel},
  title     = {Application of the optical flow method to velocity determination in hydraulic structure models},
  series = {Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016},
  booktitle = {Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016},
  editor    = {Crookston, B. and Tullis, B.},
  isbn      = {978-1-884575-75-4},
  doi       = {10.15142/T3150628160853},
  pages     = {223 -- 232},
  year      = {2016},
  language  = {en}
}
@inproceedings{OertelBung2016,
  author    = {Oertel, M. and Bung, Daniel Bernhard},
  title     = {Scouring processes downstream a crossbar block ramp},
  series = {Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016},
  booktitle = {Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016},
  editor    = {Crookston, B. and Tullis, B.},
  isbn      = {978-1-884575-75-4},
  doi       = {10.15142/T3340628160853},
  pages     = {549 -- 559},
  year      = {2016},
  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{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{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{ValeroBung2018,
  author    = {Valero, Daniel and Bung, Daniel Bernhard},
  title     = {Vectrino profiler spatial filtering for shear flows based on the mean velocity gradient equation},
  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.1943-7900.0001485},
  year      = {2018},
  abstract  = {A new methodology is proposed to spatially filter acoustic Doppler velocimetry data from a Vectrino profiler based on the differential mean velocity equation. Lower and upper bounds are formulated in terms of physically based flow constraints. Practical implementation is discussed, and its application is tested against data gathered from an open-channel flow over a stepped macroroughness surface. The method has proven to detect outliers occurring all over the distance range sampled by the Vectrino profiler and has shown to remain applicable out of the region of validity of the velocity gradient equation. Finally, a statistical analysis suggests that physically obtained bounds are asymptotically representative.},
  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}
}
@inproceedings{BungOertel2019,
  author    = {Bung, Daniel Bernhard and Oertel, Mario},
  title     = {Wave breaking over a submerged horizontal plate: Optical Flow, LES and RANS},
  series = {E-proceedings of the 38th IAHR World Congress September 1-6, 2019, Panama City, Panama},
  booktitle = {E-proceedings of the 38th IAHR World Congress September 1-6, 2019, Panama City, Panama},
  doi       = {10.3850/38WC092019-0509},
  pages     = {3690 -- 3698},
  year      = {2019},
  language  = {en}
}
@inproceedings{ValeroKramerBungetal.2019,
  author    = {Valero, Daniel and Kramer, Matthias and Bung, Daniel Bernhard and Chanson, Hubert},
  title     = {A stochastic bubble generator for air-water flow research},
  series = {E-proceedings of the 38th IAHR World Congress, September 1-6, 2019, Panama City, Panama},
  booktitle = {E-proceedings of the 38th IAHR World Congress, September 1-6, 2019, Panama City, Panama},
  doi       = {10.3850/38WC092019-0909},
  pages     = {5714 -- 5721},
  year      = {2019},
  language  = {en}
}