@article{Kirsch2010,
  author    = {Kirsch, Ansgar},
  title     = {Experimental investigation of the face stability of shallow tunnels in sand},
  series = {Acta Geotechnica},
  volume    = {5},
  journal   = {Acta Geotechnica},
  number    = {1},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1861-1125},
  doi       = {10.1007/s11440-010-0110-7},
  pages     = {43 -- 62},
  year      = {2010},
  abstract  = {Various models have been proposed for the prediction of the necessary support pressure at the face of a shallow tunnel. To assess their quality, the collapse of a tunnel face was modelled with small-scale model tests at single gravity. The development of the failure mechanism and the support force at the face in dry sand were investigated. The observed displacement patterns show a negligible influence of overburden on the extent and evolution of the failure zone. The latter is significantly influenced, though, by the initial density of the sand: in dense sand a chimney-wedge-type collapse mechanism developed, which propagated towards the soil surface. Initially, loose sand did not show any discrete collapse mechanism. The necessary support force was neither influenced by the overburden nor the initial density. A comparison with quantitative predictions by several theoretical models showed that the measured necessary support pressure is overestimated by most of the models. Those by Vermeer/Ruse and L{\´e}ca/Dormieux showed the best agreement to the measurements.},
  language  = {en}
}
@article{HoettgesFeldhausBrockhausetal.1992,
  author    = {H{\"o}ttges, J{\"o}rg and Feldhaus, R. and Brockhaus, T. and Rouv{\´e}, Gerhard},
  title     = {Finite Element Simulation of Flow and Pollution Transport applied to a Part of the River Rhine / Feldhaus, R.; J. H{\"o}ttges, T. Brockhaus; G. Rouv{\´e}},
  series = {Hydraulic and environmental modelling : proceedings of the Second International Conference on Hydraulic and Environmental Modelling of Coastal, Estuarine, and River Waters / [IAHR-AIRH]. Ed. by R. A. Falconer},
  journal   = {Hydraulic and environmental modelling : proceedings of the Second International Conference on Hydraulic and Environmental Modelling of Coastal, Estuarine, and River Waters / [IAHR-AIRH]. Ed. by R. A. Falconer},
  publisher = {Ashgate},
  address   = {Aldershot, Hants, UK [u.a.]},
  year      = {1992},
  language  = {en}
}
@article{KerresGredigkHoffmannJatheetal.2020,
  author    = {Kerres, Karsten and Gredigk-Hoffmann, Sylvia and Jathe, R{\"u}diger and Orlik, Stefan and Sariyildiz, Mustafa and Schmidt, Torsten and Sympher, Klaus-Jochen and Uhlenbroch, Adrian},
  title     = {Future approaches for sewer system condition assessment},
  series = {Water Practice \& Technology},
  journal   = {Water Practice \& Technology},
  number    = {15 (2)},
  publisher = {IWA Publishing},
  address   = {London},
  issn      = {1751-231X},
  doi       = {10.2166/wpt.2020.027},
  pages     = {386 -- 393},
  year      = {2020},
  abstract  = {Different analytical approaches exist to describe the structural substance or wear reserve of sewer systems. The aim is to convert engineering assessments of often complex defect patterns into computational algorithms and determine a substance class for a sewer section or manhole. This analytically determined information is essential for strategic rehabilitation planning processes up to network level, as it corresponds to the most appropriate rehabilitation type and can thus provide decision-making support. Current calculation methods differ clearly from each other in parts, so that substance classes determined by the different approaches are only partially comparable with each other. The objective of the German R\&D cooperation project 'SubKanS' is to develop a methodology for classifying the specific defect patterns resulting from the interaction of all the individual defects, and their severities and locations. The methodology takes into account the structural substance of sewer sections and manholes, based on real data and theoretical considerations analogous to the condition classification of individual defects. The result is a catalogue of defect patterns and characteristics, as well as associated structural substance classifications of sewer systems (substance classes). The methodology for sewer system substance classification is developed so that the classification of individual defects can be transferred into a substance class of the sewer section or manhole, eventually taking into account further information (e.g. pipe material, nominal diameter, etc.). The result is a validated methodology for automated sewer system substance classification.},
  language  = {en}
}
@article{BienerBoykenSasseetal.1999,
  author    = {Biener, Ernst and Boyken, P. and Sasse, T. and Arnold, J.},
  title     = {Geotechnical aspects of the construction of the integrated harbour sludge management system in Bremen-Seehausen / P. Boyken ; E. Biener ; T. Sasse ; J. Arnold},
  series = {Geotechnical engineering for transportation infrastructure : proceedings of the twelfth European Conference on Soil Mechanics and Geotechnical Engineering, Amsterdam, Netherlands, 7 - 10 June 1999 ; theory and practice, planning and design, construction and maintenance. - Vol. 2},
  journal   = {Geotechnical engineering for transportation infrastructure : proceedings of the twelfth European Conference on Soil Mechanics and Geotechnical Engineering, Amsterdam, Netherlands, 7 - 10 June 1999 ; theory and practice, planning and design, construction and maintenance. - Vol. 2},
  publisher = {Balkema},
  address   = {Rotterdam},
  isbn      = {90-5809-049-3},
  pages     = {909 -- 914},
  year      = {1999},
  language  = {en}
}
@article{ErpicumCrookstonBombardellietal.2021,
  author    = {Erpicum, Sebastien and Crookston, Brian M. and Bombardelli, Fabian and Bung, Daniel B. 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{KuhnhenneRegerPyschnyetal.2020,
  author    = {Kuhnhenne, Markus and Reger, Vitali and Pyschny, Dominik and D{\"o}ring, Bernd},
  title     = {Influence of airtightness of steel sandwich panel joints on heat losses},
  series = {E3S Web of Conferences 12th Nordic Symposium on Building Physics (NSB 2020)},
  volume    = {172},
  journal   = {E3S Web of Conferences 12th Nordic Symposium on Building Physics (NSB 2020)},
  number    = {Art. 05008},
  publisher = {EDP Sciences},
  address   = {Les Ulis},
  doi       = {10.1051/e3sconf/202017205008},
  pages     = {6},
  year      = {2020},
  abstract  = {Energy saving ordinances requires that buildings must be designed in such a way that the heat transfer surface including the joints is permanently air impermeable. The prefabricated roof and wall panels in lightweight steel constructions are airtight in the area of the steel covering layers. The sealing of the panel joints contributes to fulfil the comprehensive requirements for an airtight building envelope. To improve the airtightness of steel sandwich panels, additional sealing tapes can be installed in the panel joint. The influence of these sealing tapes was evaluated by measurements carried out by the RWTH Aachen University - Sustainable Metal Building Envelopes. Different installation situations were evaluated by carrying out airtightness tests for different joint distances. In addition, the influence on the heat transfer coefficient was also evaluated using the Finite Element Method (FEM). The combination of obtained air volume flow and transmission losses enables to create an "effective heat transfer coefficient" due to transmission and infiltration. This summarizes both effects in one value and is particularly helpful for approximate calculations on energy efficiency.},
  language  = {en}
}
@article{OertelBung2012,
  author    = {Oertel, Mario and Bung, Daniel B.},
  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{BienerBoykenSasse1997,
  author    = {Biener, Ernst and Boyken, P. and Sasse, T.},
  title     = {Integrated dredged material management system of Bremen-Seehausen},
  series = {Sardinia 97 : proceedings ; [13 - 17 October 1997, S. Margherita di Pula - Cagliari, Sardinia, Italy] / Sixth International Landfill Symposium. Ed.: Thomas H. Christensen... - Bd. 5 : Landfill regulations, waste characteristics, landfilling in middle and lower income countries, industrial wastes and monolandfills},
  journal   = {Sardinia 97 : proceedings ; [13 - 17 October 1997, S. Margherita di Pula - Cagliari, Sardinia, Italy] / Sixth International Landfill Symposium. Ed.: Thomas H. Christensen... - Bd. 5 : Landfill regulations, waste characteristics, landfilling in middle and lower income countries, industrial wastes and monolandfills},
  publisher = {CISA, Environmental Sanitary Engineering Centre},
  address   = {Cagliari},
  pages     = {497 -- 502},
  year      = {1997},
  language  = {en}
}
@article{HoettgesArnoldRouve1994,
  author    = {H{\"o}ttges, J{\"o}rg and Arnold, Uwe and Rouv{\´e}, Gerhard},
  title     = {Measurement of transverse mixing using digital image acquisition},
  series = {Mixing and transport in the environment : a memorial volume for Catherine M. Allen (1954-1991) / ed. by Keith J. Beven},
  journal   = {Mixing and transport in the environment : a memorial volume for Catherine M. Allen (1954-1991) / ed. by Keith J. Beven},
  publisher = {Wiley},
  address   = {Chichester [u.a.]},
  isbn      = {0471941425},
  pages     = {XVI, 458 S., [8] Bl : Ill. (z.T. farb.), graph. Da},
  year      = {1994},
  language  = {en}
}
@article{LeandroBungCarvalho2014,
  author    = {Leandro, J. and Bung, Daniel B. 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{BlankeHagenkampDoeringetal.2021,
  author    = {Blanke, Tobias and Hagenkamp, Markus and D{\"o}ring, Bernd and G{\"o}ttsche, Joachim and Reger, Vitali and Kuhnhenne, Markus},
  title     = {Net-exergetic, hydraulic and thermal optimization of coaxial heat exchangers using fixed flow conditions instead of fixed flow rates},
  series = {Geothermal Energy},
  volume    = {9},
  journal   = {Geothermal Energy},
  number    = {Article number: 19},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {2195-9706},
  doi       = {10.1186/s40517-021-00201-3},
  pages     = {23 Seiten},
  year      = {2021},
  abstract  = {Previous studies optimized the dimensions of coaxial heat exchangers using constant mass fow rates as a boundary condition. They show a thermal optimal circular ring width of nearly zero. Hydraulically optimal is an inner to outer pipe radius ratio of 0.65 for turbulent and 0.68 for laminar fow types. In contrast, in this study, fow conditions in the circular ring are kept constant (a set of fxed Reynolds numbers) during optimization. This approach ensures fxed fow conditions and prevents inappropriately high or low mass fow rates. The optimization is carried out for three objectives: Maximum energy gain, minimum hydraulic efort and eventually optimum net-exergy balance. The optimization changes the inner pipe radius and mass fow rate but not the Reynolds number of the circular ring. The thermal calculations base on Hellstr{\"o}m's borehole resistance and the hydraulic optimization on individually calculated linear loss of head coefcients. Increasing the inner pipe radius results in decreased hydraulic losses in the inner pipe but increased losses in the circular ring. The net-exergy diference is a key performance indicator and combines thermal and hydraulic calculations. It is the difference between thermal exergy fux and hydraulic efort. The Reynolds number in the circular ring is instead of the mass fow rate constant during all optimizations. The result from a thermal perspective is an optimal width of the circular ring of nearly zero. The hydraulically optimal inner pipe radius is 54\% of the outer pipe radius for laminar fow and 60\% for turbulent fow scenarios. Net-exergetic optimization shows a predominant infuence of hydraulic losses, especially for small temperature gains. The exact result depends on the earth's thermal properties and the fow type. Conclusively, coaxial geothermal probes' design should focus on the hydraulic optimum and take the thermal optimum as a secondary criterion due to the dominating hydraulics.},
  language  = {en}
}
@article{BienerSasseArnoldetal.1999,
  author    = {Biener, Ernst and Sasse, T. and Arnold, J. and Woltering, S.},
  title     = {New treatment of harbour sludge in Bremen and Bremerhaven / E. Biener ; T. Sasse ; J. Arnold ; S. Woltering ; N. Binder},
  series = {Characterisation and treatment of sediments : Antwerpen, Belgium, September 15 - 17, 1999 ; [preceded by 12th International Harbour Congress] ; proceedings / CATS 4. Ed.: G. De Schutter. Organized by: Technologisch Instituut, Koninklijke Vlaamse Ingenieursvereniging},
  journal   = {Characterisation and treatment of sediments : Antwerpen, Belgium, September 15 - 17, 1999 ; [preceded by 12th International Harbour Congress] ; proceedings / CATS 4. Ed.: G. De Schutter. Organized by: Technologisch Instituut, Koninklijke Vlaamse Ingenieursvereniging},
  publisher = {Technolog. Inst.},
  address   = {Anvers},
  isbn      = {9076019118},
  pages     = {115 -- 122},
  year      = {1999},
  language  = {en}
}
@article{Bung2013,
  author    = {Bung, Daniel B.},
  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{ValeroVitiGualtieri2019,
  author    = {Valero, Daniel and Viti, Nicolo and Gualtieri, Carlo},
  title     = {Numerical Simulation of Hydraulic Jumps. Part 1: Experimental Data for Modelling Performance Assessment},
  series = {Water},
  volume    = {11},
  journal   = {Water},
  number    = {1},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2073-4441},
  doi       = {10.3390/w11010036},
  pages     = {Art. Nr. 36},
  year      = {2019},
  language  = {en}
}
@article{VitiValeroGualtieri2019,
  author    = {Viti, Nicolo and Valero, Daniel and Gualtieri, Carlo},
  title     = {Numerical Simulation of Hydraulic Jumps. Part 2: Recent Results and Future Outlook},
  series = {Water},
  volume    = {11},
  journal   = {Water},
  number    = {1},
  issn      = {2073-4441},
  doi       = {10.3390/w11010028},
  pages     = {Art. Nr. 28},
  year      = {2019},
  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{CheenakulaPaulsenOttetal.2023,
  author    = {Cheenakula, Dheeraja and Paulsen, Svea and Ott, Fabian and Gr{\"o}mping, Markus},
  title     = {Operational window of a deammonifying sludge for mainstream application in a municipal wastewater treatment plant},
  series = {Water and Environment Journal},
  journal   = {Water and Environment Journal},
  number    = {Early View},
  publisher = {Wiley},
  address   = {Chichester},
  issn      = {1747-6593},
  doi       = {10.1111/wej.12898},
  pages     = {1 -- 12},
  year      = {2023},
  abstract  = {The present work aimed to study the mainstream feasibility of the deammonifying sludge of side stream of municipal wastewater treatment plant (MWWTP) in Kaster, Germany. For this purpose, the deammonifying sludge available at the side stream was investigated for nitrogen (N) removal with respect to the operational factors temperature (15-30°C), pH value (6.0-8.0) and chemical oxygen demand (COD)/N ratio (≤1.5-6.0). The highest and lowest N-removal rates of 0.13 and 0.045 kg/(m³ d) are achieved at 30 and 15°C, respectively. Different conditions of pH and COD/N ratios in the SBRs of Partial nitritation/anammox (PN/A) significantly influenced both the metabolic processes and associated N-removal rates. The scientific insights gained from the current work signifies the possibility of mainstream PN/A at WWTPs. The current study forms a solid basis of operational window for the upcoming semi-technical trails to be conducted prior to the full-scale mainstream PN/A at WWTP Kaster and WWTPs globally.},
  language  = {en}
}
@article{BungValero2016,
  author    = {Bung, Daniel B. 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{HoettgesRitterbachEls1987,
  author    = {H{\"o}ttges, J{\"o}rg and Ritterbach, E. and Els, H.},
  title     = {Optical Improvement of LDV-Measurement in Pipe Flow / Ritterbach, E.; J. H{\"o}ttges; H. Els},
  series = {Laser anemometry : advances and applications; proceedings of the 2. International Conference, Strathclyde, Scotland, 21st to 23rd September 1987 / ed. by John Turner ... UK LDA Users Group},
  journal   = {Laser anemometry : advances and applications; proceedings of the 2. International Conference, Strathclyde, Scotland, 21st to 23rd September 1987 / ed. by John Turner ... UK LDA Users Group},
  publisher = {Springer},
  address   = {Berlin [u.a.]},
  isbn      = {3540187561},
  pages     = {VII, 601 S : Ill., graph. Darst.},
  year      = {1987},
  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}
}