@article{ValeroBungCrookston2018,
  author    = {Valero, Daniel and Bung, Daniel B. 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{ZhangValeroBungetal.2018,
  author    = {Zhang, G. and Valero, Daniel and Bung, Daniel B. 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{BungValero2018,
  author    = {Bung, Daniel B. and Valero, Daniel},
  title     = {Re-aeration on stepped spillways with special consideration of entrained and entrapped air},
  series = {Geosciences},
  volume    = {8},
  journal   = {Geosciences},
  number    = {9},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2076-3263},
  pages     = {Article number 333},
  year      = {2018},
  abstract  = {As with most high-velocity free-surface flows, stepped spillway flows become self-aerated when the drop height exceeds a critical value. Due to the step-induced macro-roughness, the flow field becomes more turbulent than on a similar smooth-invert chute. For this reason, cascades are oftentimes used as re-aeration structures in wastewater treatment. However, for stepped spillways as flood release structures downstream of deoxygenated reservoirs, gas transfer is also of crucial significance to meet ecological requirements. Prediction of mass transfer velocities becomes challenging, as the flow regime differs from typical previously studied flow conditions. In this paper, detailed air-water flow measurements are conducted on stepped spillway models with different geometry, with the aim to estimate the specific air-water interface. Re-aeration performances are determined by applying the absorption method. In contrast to earlier studies, the aerated water body is considered a continuous mixture up to a level where 75\% air concentration is reached. Above this level, a homogenous surface wave field is considered, which is found to significantly affect the total air-water interface available for mass transfer. Geometrical characteristics of these surface waves are obtained from high-speed camera investigations. The results show that both the mean air concentration and the mean flow velocity have influence on the mass transfer. Finally, an empirical relationship for the mass transfer on stepped spillway models is proposed.},
  language  = {en}
}
@inproceedings{BungTullis2018,
  author    = {Bung, Daniel B. and Tullis, Blake},
  title     = {Hydraulic Structures - ISHS2018 in Perspective},
  series = {7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May},
  booktitle = {7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May},
  isbn      = {978-0-692-13277-7},
  doi       = {10.15142/T3WH2B},
  pages     = {9 seiten},
  year      = {2018},
  language  = {en}
}
@inproceedings{ValeroVogelSchmidtetal.2018,
  author    = {Valero, Daniel and Vogel, Jochen and Schmidt, Daniel and Bung, Daniel B.},
  title     = {Three-dimensional flow structure inside the cavity of a non-aerated stepped chute},
  series = {7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May},
  booktitle = {7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May},
  isbn      = {978-0-692-13277-7},
  doi       = {10.15142/T3GH17},
  pages     = {12 Seiten},
  year      = {2018},
  language  = {en}
}
@article{KramerValeroChansonetal.2019,
  author    = {Kramer, Matthias and Valero, Daniel and Chanson, Hubert and Bung, Daniel B.},
  title     = {Towards reliable turbulence estimations with phase-detection probes: an adaptive window cross-correlation technique},
  series = {Experiments in Fluids},
  volume    = {60},
  journal   = {Experiments in Fluids},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1432-1114},
  doi       = {10.1007/s00348-018-2650-9},
  year      = {2019},
  language  = {en}
}
@article{ValeroChansonBung2019,
  author    = {Valero, Daniel and Chanson, Hubert and Bung, Daniel B.},
  title     = {Robust estimators for turbulence properties assessment},
  pages     = {1 -- 24},
  year      = {2019},
  language  = {en}
}
@article{ValeroBungCrookston2019,
  author    = {Valero, D. and Bung, Daniel B. 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}
}
@inproceedings{ValeroKramerBungetal.2019,
  author    = {Valero, Daniel and Kramer, Matthias and Bung, Daniel B. 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}
}
@inproceedings{TullisCrookstonBung2019,
  author    = {Tullis, Blake P. and Crookston, Brian M. and Bung, Daniel B.},
  title     = {Weir head-discharge relationships: A multi-lab exercise},
  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},
  pages     = {1 -- 15},
  year      = {2019},
  language  = {en}
}