TY  - JOUR
A1  - Bayon, Arnau
A1  - Valero, Daniel
A1  - Garcia-Bartual, Rafael
A1  - Vallés-Morán, Francisco José
A1  - López-Jiménez, P. Amparo
T1  - Performance assessment of OpenFOAM and FLOW-3D in the numerical modeling of a low Reynolds number hydraulic jump
JF  - Environmental Modelling & Software
N2  - A comparative performance analysis of the CFD platforms OpenFOAM and FLOW-3D is presented, focusing on a 3D swirling turbulent flow: a steady hydraulic jump at low Reynolds number. Turbulence is treated using RANS approach RNG k-ε. A Volume Of Fluid (VOF) method is used to track the air–water interface, consequently aeration is modeled using an Eulerian–Eulerian approach. Structured meshes of cubic elements are used to discretize the channel geometry. The numerical model accuracy is assessed comparing representative hydraulic jump variables (sequent depth ratio, roller length, mean velocity profiles, velocity decay or free surface profile) to experimental data. The model results are also compared to previous studies to broaden the result validation. Both codes reproduced the phenomenon under study concurring with experimental data, although special care must be taken when swirling flows occur. Both models can be used to reproduce the hydraulic performance of energy dissipation structures at low Reynolds numbers.
Y1  - 2016
SN  - 1364-8152
U6  - http://dx.doi.org/10.1016/j.envsoft.2016.02.018
VL  - 80
SP  - 322
EP  - 335
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Biener, Ernst
T1  - Rehabilitation of old gravity dams
JF  - [Transactions] : proceedings of fifteenth international congress on large dams ; 24 - 28 Juin 1985, Lausanne, Suisse = Quinzieme Congres International des Grands Barrages. - Bd. 4
Y1  - 1985
N1  - International Congress on Large Dams <15, 1985, Paris>
SP  - Q 59, R.2, S. 21
EP  - 23
PB  - Intern. Commission on Large Dams
CY  - Paris
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Bethke, H.
A1  - Sasse, T.
A1  - Wernhoff, T.
T1  - Alternative landfill capping using locally available recycled material
JF  - Land contamination & reclamation. 14 (2003), H. 4
Y1  - 2003
SN  - 0967-0513
SP  - 419
EP  - 427
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Boyken, P.
A1  - Sasse, T.
T1  - Integrated dredged material management system of Bremen-Seehausen
JF  - 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
Y1  - 1997
N1  - International Landfill Symposium <6, 1997, Santa Margherita, Pula>
SP  - 497
EP  - 502
PB  - CISA, Environmental Sanitary Engineering Centre
CY  - Cagliari
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Boyken, P.
A1  - Sasse, T.
A1  - Arnold, J.
T1  - Geotechnical aspects of the construction of the integrated harbour sludge management system in Bremen-Seehausen / P. Boyken ;  E. Biener ; T. Sasse ; J. Arnold
JF  - 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
Y1  - 1999
SN  - 90-5809-049-3
N1  - European Conference on Soil Mechanics and Geotechnical Engineering <12, 1999, Amsterdam>
SP  - 909
EP  - 914
PB  - Balkema
CY  - Rotterdam
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Rouvé, G.
T1  - Behaviour and maintenance of some old masonry gravity dams
JF  - Safety of dams : proceedings of the International Conference on Safety of Dams, Coimbra, 23-28 April 1984 / ed. by J. Laginha Serafim. - [Hauptbd.]
Y1  - 1984
SN  - 90-6191-522-8
N1  - International Conference on Safety of Dams <1984, Coimbra> ; ISBN Set: 90-6191-521-X
SP  - 101
EP  - 106
PB  - Rotterdam [u.a.]
CY  - Balkema
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Sasse, T.
T1  - Construction and rehabilitation of landfill shafts
JF  - Sardinia 93 : Fourth International Landfill Symposium "Barrier systems, environmental aspects, upgrading and remediation, siting, monofills, effects of waste pretreatment, landfilling in developing countries" ; 11 - 15 October 1993, S. Margherita di Pula (Cagliari), Sardinia, Italy ; proceedings / coord. by Thomas H. Christensen ... - Bd. 1
Y1  - 1993
N1  - International Landfill Symposium <4, 1993, Santa Margherita, Pula>
SP  - 451
EP  - 460
PB  - CISA, Environmental Sanitary Engineering Centre
CY  - Cagliari
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Sasse, T.
T1  - Quality improvements in the construction of multilayer covers
JF  - Géologie et confinement des déchets toxiques : actes du symposium international, 8 - 11 juin 1993 / GEOCONFINE 93, Montpellier, France. Réd. Marcel Arnould
Y1  - 1993
SN  - 90-5410-330-2
N1  - Geoconfine <1993, Montpellier> ; Paralellt.: Geology and confinement of toxic wastes
SP  - 309
EP  - 312
PB  - Balkema
CY  - Rotterdam [u.a.]
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Sasse, T.
T1  - Construction of composite lining systems under unfavourable weather conditions
JF  - Landfilling of waste: barriers / ed. by T. H. Christensen; R. Cossu; R. Stegmann. - 1. Aufl.
Y1  - 1994
SN  - 0419159908
SP  - 183
EP  - 200
PB  - Spon
CY  - London [u.a.]
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Sasse, T.
T1  - Experience with new techniques in slurry cutoff wall construction
JF  - ISWA 88, proceedings of the 5th International Solid Wastes Conference : September 11 - 16th, 1988, Copenhagen, Denmark / ed. by Lizzi Andersen ... - Vol. 1 : Oral presentations
Y1  - 1988
SN  - 0-12-058451-4
N1  - International Solid Wastes Conference <5, 1988, København> ; International Solid Wastes and Public Cleansing Association
SP  - 41
EP  - 46
PB  - Acad. Press
CY  - London [u.a.]
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Sasse, T.
A1  - Arnold, J.
A1  - Woltering, S.
T1  - New treatment of harbour sludge in Bremen and Bremerhaven  /  E. Biener ; T. Sasse ; J. Arnold ; S. Woltering ; N. Binder
JF  - 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
Y1  - 1999
SN  - 9076019118
N1  - CATS <4, 1999, Anvers>
SP  - 115
EP  - 122
PB  - Technolog. Inst.
CY  - Anvers
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Sasse, T.
A1  - Bökers, H.
T1  - Preliminary or final capping of sanitary landfills? : Technical and economical aspects
JF  - Sardinia 99 : proceedings / Seventh International Waste Management and Landfill Symposium, [4 - 8 October 1999, S. Margherita di Pula, Cagliari, Sardinia, Italy]. Ed.: Thomas H. Christensen. -  Bd. 3 : Barriers, waste mechanics and landfill design
Y1  - 1999
N1  - International Waste Management and Landfill Symposium <7, 1999, Cagliari>
SP  - 287
EP  - 294
PB  - CISA, Environmental Sanitary Engineering Centre
CY  - Cagliari
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Sasse, T.
A1  - Konertz, K.
T1  - Preparation of mineral sealing materials for landfills by different processing technologies / Sasse, T. ; Biener, E. ; Konertz, K.
JF  - Sardinia 93 : Fourth International Landfill Symposium "Barrier systems, environmental aspects, upgrading and remediation, siting, monofills, effects of waste pretreatment, landfilling in developing countries" ; 11 - 15 October 1993, S. Margherita di Pula (Cagliari), Sardinia, Italy ; proceedings / coord. by Thomas H. Christensen ... - Bd. 1
Y1  - 1993
N1  - International Landfill Symposium <4, 1993, Santa Margherita, Pula>
SP  - 275
EP  - 283
PB  - CISA, Environmental Sanitary Engineering Centre
CY  - Cagliari
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Sasse, T.
A1  - Wernhoff, T.
T1  - Using harbour dredged material for combination sealing of the former Bockhorner Weg disposal site in Bremen, Germany
JF  - Proceedings of the International Harbour Congress. 13 (2003)
Y1  - 2003
N1  - International Harbour Congress <13, 2003, Antwerpen>
SP  - 101
EP  - 109
ER  - 
TY  - JOUR
A1  - Biener, Ernst
A1  - Wemhoff, T.
A1  - Bethke, H.
T1  - Stability and settlement problems based on the example of the Blockland landfill in Bremen
JF  - Sardinia 95 : Fifth International Landfill Symposium ; (2 - 6 October 1995, S. Margheritadi Pula - Cagliari, Sardinia, Italy) ; proceedings / coord.: Thomas H. Christensen ... - Bd. 2 : Siting, lining, drainage & landfill mechanics
Y1  - 1995
N1  - International Landfill Symposium <5, 1995, Santa Margherita, Pula>
SP  - 843
EP  - 853
PB  - CISA, Environmental Sanitary Engineering Centre
CY  - Cagliari
ER  - 
TY  - JOUR
A1  - Blanke, Tobias
A1  - Hagenkamp, Markus
A1  - Döring, Bernd
A1  - Göttsche, Joachim
A1  - Reger, Vitali
A1  - Kuhnhenne, Markus
T1  - Net-exergetic, hydraulic and thermal optimization of coaxial heat exchangers using fixed flow conditions instead of fixed flow rates
JF  - Geothermal Energy
N2  - 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 Hellström’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.
Y1  - 2021
U6  - http://dx.doi.org/10.1186/s40517-021-00201-3
SN  - 2195-9706
N1  - Corresponding author: Tobias Blanke
VL  - 9
IS  - Article number: 19
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Bung, Daniel B.
T1  - Non-intrusive detection of air–water surface roughness in self-aerated chute flows
JF  - Journal of hydraulic research
Y1  - 2013
SN  - 1814-2079 (E-Journal); 0022-1686 (Print)
VL  - Vol. 51
IS  - Iss. 3
SP  - 322
EP  - 329
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Bung, Daniel B.
T1  - Developing flow in skimming flow regime on embankment stepped spillways
JF  - Journal of hydraulic research
Y1  - 2011
SN  - 1814-2079 (E-Journal); 0022-1686 (Print)
VL  - Vol. 49
IS  - Iss. 5
SP  - 639
EP  - 648
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Bung, Daniel B.
A1  - Crookston, Brian M.
A1  - Valero, Daniel
T1  - Turbulent free-surface monitoring with an RGB-D sensor: the hydraulic jump case
JF  - Journal of Hydraulic Research
Y1  - 2020
U6  - http://dx.doi.org/10.1080/00221686.2020.1844810
SN  - 1814-2079
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Bung, Daniel B.
A1  - Valero, Daniel
T1  - Re-aeration on stepped spillways with special consideration of entrained and entrapped air
JF  - Geosciences
N2  - 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.
Y1  - 2018
SN  - 2076-3263
VL  - 8
IS  - 9
SP  - Article number 333
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Bung, Daniel B.
A1  - Valero, Daniel
T1  - Optical flow estimation in aerated flows
JF  - Journal of Hydraulic Research
N2  - 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.
Y1  - 2016
U6  - http://dx.doi.org/10.1080/00221686.2016.1173600
VL  - 54
IS  - 5
SP  - 575
EP  - 580
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Bung, Daniel Bernhard
A1  - Erpicum, Sébastien
A1  - Tullis, Blanke P.
T1  - Advances in hydraulic structures engineering
JF  - Journal of Hydraulic Engineering
Y1  - 2020
U6  - http://dx.doi.org/10.1061/(ASCE)HY.1943-7900.0001851
SN  - 0733-9429 (Druckausgabe)
SN  - 1943-7900 (Online-Ausgabe)
VL  - 147
IS  - 1
PB  - ASCE
CY  - Reston, Va.
ER  - 
TY  - JOUR
A1  - Cheenakula, Dheeraja
A1  - Griebel, Kai
A1  - Montag, David
A1  - Grömping, Markus
ED  - Huang, Xiaowu
T1  - Concept development of a mainstream deammonification and comparison with conventional process in terms of energy, performance and economical construction perspectives
JF  - Frontiers in Microbiology
N2  - Deammonification for nitrogen removal in municipal wastewater in temperate and cold climate zones is currently limited to the side stream of municipal wastewater treatment plants (MWWTP). This study developed a conceptual model of a mainstream deammonification plant, designed for 30,000 P.E., considering possible solutions corresponding to the challenging mainstream conditions in Germany. In addition, the energy-saving potential, nitrogen elimination performance and construction-related costs of mainstream deammonification were compared to a conventional plant model, having a single-stage activated sludge process with upstream denitrification. The results revealed that an additional treatment step by combining chemical precipitation and ultra-fine screening is advantageous prior the mainstream deammonification. Hereby chemical oxygen demand (COD) can be reduced by 80% so that the COD:N ratio can be reduced from 12 to 2.5. Laboratory experiments testing mainstream conditions of temperature (8–20°C), pH (6–9) and COD:N ratio (1–6) showed an achievable volumetric nitrogen removal rate (VNRR) of at least 50 gN/(m3∙d) for various deammonifying sludges from side stream deammonification systems in the state of North Rhine-Westphalia, Germany, where m3 denotes reactor volume. Assuming a retained Norganic content of 0.0035 kgNorg./(P.E.∙d) from the daily loads of N at carbon removal stage and a VNRR of 50 gN/(m3∙d) under mainstream conditions, a resident-specific reactor volume of 0.115 m3/(P.E.) is required for mainstream deammonification. This is in the same order of magnitude as the conventional activated sludge process, i.e., 0.173 m3/(P.E.) for an MWWTP of size class of 4. The conventional plant model yielded a total specific electricity demand of 35 kWh/(P.E.∙a) for the operation of the whole MWWTP and an energy recovery potential of 15.8 kWh/(P.E.∙a) through anaerobic digestion. In contrast, the developed mainstream deammonification model plant would require only a 21.5 kWh/(P.E.∙a) energy demand and result in 24 kWh/(P.E.∙a) energy recovery potential, enabling the mainstream deammonification model plant to be self-sufficient. The retrofitting costs for the implementation of mainstream deammonification in existing conventional MWWTPs are nearly negligible as the existing units like activated sludge reactors, aerators and monitoring technology are reusable. However, the mainstream deammonification must meet the performance requirement of VNRR of about 50 gN/(m3∙d) in this case.
KW  - anammox
KW  - energy efficiency
KW  - mainstream deammonification
KW  - nitrogen elimination
KW  - wastewater
Y1  - 2023
U6  - http://dx.doi.org/10.3389/fmicb.2023.1155235
SN  - 1664-302X
VL  - 14
IS  - 11155235
SP  - 1
EP  - 15
PB  - Frontiers
ER  - 
TY  - JOUR
A1  - Cheenakula, Dheeraja
A1  - Hoffstadt, Kevin
A1  - Krafft, Simone
A1  - Reinecke, Diana
A1  - Klose, Holger
A1  - Kuperjans, Isabel
A1  - Grömping, Markus
T1  - Anaerobic digestion of algal–bacterial biomass of an Algal Turf Scrubber system
JF  - Biomass Conversion and Biorefinery
N2  - This study investigated the anaerobic digestion of an algal–bacterial biofilm grown in artificial wastewater in an Algal Turf Scrubber (ATS). The ATS system was located in a greenhouse (50°54′19ʺN, 6°24′55ʺE, Germany) and was exposed to seasonal conditions during the experiment period. The methane (CH4) potential of untreated algal–bacterial biofilm (UAB) and thermally pretreated biofilm (PAB) using different microbial inocula was determined by anaerobic batch fermentation. Methane productivity of UAB differed significantly between microbial inocula of digested wastepaper, a mixture of manure and maize silage, anaerobic sewage sludge, and percolated green waste. UAB using sewage sludge as inoculum showed the highest methane productivity. The share of methane in biogas was dependent on inoculum. Using PAB, a strong positive impact on methane productivity was identified for the digested wastepaper (116.4%) and a mixture of manure and maize silage (107.4%) inocula. By contrast, the methane yield was significantly reduced for the digested anaerobic sewage sludge (50.6%) and percolated green waste (43.5%) inocula. To further evaluate the potential of algal–bacterial biofilm for biogas production in wastewater treatment and biogas plants in a circular bioeconomy, scale-up calculations were conducted. It was found that a 0.116 km2 ATS would be required in an average municipal wastewater treatment plant which can be viewed as problematic in terms of space consumption. However, a substantial amount of energy surplus (4.7–12.5 MWh a−1) can be gained through the addition of algal–bacterial biomass to the anaerobic digester of a municipal wastewater treatment plant. Wastewater treatment and subsequent energy production through algae show dominancy over conventional technologies.
KW  - Biogas
KW  - Methane
KW  - Algal Turf Scrubber
KW  - Algal–bacterial bioflm
KW  - Circular bioeconomy
Y1  - 2022
U6  - http://dx.doi.org/10.1007/s13399-022-03236-z
SN  - 2190-6823
N1  - Corresponding author: Dheeraja Cheenakula
VL  - 13
SP  - 15 Seiten
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Cheenakula, Dheeraja
A1  - Paulsen, Svea
A1  - Ott, Fabian
A1  - Grömping, Markus
T1  - Operational window of a deammonifying sludge for mainstream application in a municipal wastewater treatment plant
JF  - Water and Environment Journal
N2  - 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.
KW  - Anammox
KW  - Mainstream
KW  - Nitrogen removal
KW  - Partial nitritation
KW  - Wastewater
Y1  - 2023
U6  - http://dx.doi.org/10.1111/wej.12898
SN  - 1747-6593
N1  - Corresponding author: Dheeraja Cheenakula
IS  - Early View
SP  - 1
EP  - 12
PB  - Wiley
CY  - Chichester
ER  - 
TY  - JOUR
A1  - Döring, Bernd
A1  - Kendrick, C.
A1  - Lawson, R. M.
T1  - Thermal capacity of composite floor slabs
JF  - Energy and buildings
Y1  - 2013
SN  - 1872-6178 (E-Journal); 0378-7788 (Print)
VL  - Vol. 67
SP  - 531
EP  - 539
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Döring, Bernd
A1  - Reger, Vitali
A1  - Kuhnhenne, Markus
A1  - Feldmann, Markus
A1  - Kesti, Jyrki
A1  - Lawson, Mark
A1  - Botti, Andrea
T1  - Steel solutions for enabling zero-energy buildings
JF  - Steel Construction - Design
and Research
Y1  - 2015
U6  - http://dx.doi.org/10.1002/stco.201510029
SN  - 1867-0539
N1  - The 13th Nordic Steel Construction Conference, Tampere, 2015 (NSCC-2015)
VL  - 8
IS  - 3
SP  - 194
EP  - 200
PB  - Ernst & Sohn
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Erpicum, Sebastien
A1  - Crookston, Brian M.
A1  - Bombardelli, Fabian
A1  - Bung, Daniel B.
A1  - Felder, Stefan
A1  - Mulligan, Sean
A1  - Oertel, Mario
A1  - Palermo, Michele
T1  - Hydraulic structures engineering: An evolving science in a changing world
JF  - Wires Water
Y1  - 2021
U6  - http://dx.doi.org/10.1002/wat2.1505
SN  - 2049-1948
VL  - 8
IS  - 2
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Fellin, Wolfgang
A1  - King, Julian
A1  - Kirsch, Ansgar
A1  - Oberguggenberger, Michael
T1  - Uncertainty modelling and sensitivity analysis of tunnel face stability
JF  - Structural safety
N2  - This paper proposes an approach to the choice and evaluation of engineering models with the aid of a typical application in geotechnics. An important issue in the construction of shallow tunnels, especially in weak ground conditions, is the tunnel face stability. Various theoretical and numerical models for predicting the necessary support pressure have been put forth in the literature. In this paper, we combine laboratory experiments performed at the University of Innsbruck with current methods of uncertainty and sensitivity analysis for assessing adequacy, predictive power and robustness of the models. The major issues are the handling of the twofold uncertainty of test results and of model predictions as well as the decision about what are the influential input parameters.
Y1  - 2010
U6  - http://dx.doi.org/10.1016/j.strusafe.2010.06.001
SN  - 0167-4730
VL  - 32
IS  - 6
SP  - 402
EP  - 410
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Gossla, Ulrich
A1  - Sato, R.
T1  - Present production circumstances of aggregate in Germany / Sato, R.; Gossla, U.
JF  - Cement & Concrete (1998)
Y1  - 1998
N1  - auf Japanisch
SP  - 146
EP  - 153
ER  - 
TY  - JOUR
A1  - Hagenkamp, Markus
A1  - Blanke, Tobias
A1  - Döring, Bernd
T1  - Thermoelectric building temperature control: a potential assessment
JF  - International Journal of Energy and Environmental Engineering
N2  - This study focuses on thermoelectric elements (TEE) as an alternative for room temperature control. TEE are semi-conductor devices that can provide heating and cooling via a heat pump effect without direct noise emissions and no refrigerant use. An efficiency evaluation of the optimal operating mode is carried out for different numbers of TEE, ambient temperatures, and heating loads. The influence of an additional heat recovery unit on system efficiency and an unevenly distributed heating demand are examined. The results show that TEE can provide heat at a coefficient of performance (COP) greater than one especially for small heating demands and high ambient temperatures. The efficiency increases with the number of elements in the system and is subject to economies of scale. The best COP exceeds six at optimal operating conditions. An additional heat recovery unit proves beneficial for low ambient temperatures and systems with few TEE. It makes COPs above one possible at ambient temperatures below 0 ∘C. The effect increases efficiency by maximal 0.81 (from 1.90 to 2.71) at ambient temperature 5 K below room temperature and heating demand Q˙h=100W but is subject to diseconomies of scale. Thermoelectric technology is a valuable option for electricity-based heat supply and can provide cooling and ventilation functions. A careful system design as well as an additional heat recovery unit significantly benefits the performance. This makes TEE superior to direct current heating systems and competitive to heat pumps for small scale applications with focus on avoiding noise and harmful refrigerants.
Y1  - 2021
U6  - http://dx.doi.org/10.1007/s40095-021-00424-x
N1  - Corresponding author: Markus Hagenkamp
VL  - 13
SP  - 241
EP  - 254
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
T1  - Turbulence and Mixing Mechanics in Compound Open Channel Flow / Arnold, Uwe; Höttges, Jörg; Rouvé, Gerhard
JF  - On cutoff ratios of curved channels : paper presented at the 23rd Congress of the IAHR, Ottawa, Canada, August 21 - 25, 1989 / G. J. Klaassen; B. H. J.van Zanten
Y1  - 1990
N1  - Congress of the IAHR ; (23 : ; 1989.08.21-25 : ; Ottawa)
PB  - Delft Hydraulics
CY  - Delft
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
T1  - A Full Finite Element Solution for the Unsteady Advection-Diffusion Equation
JF  - Computational methods in water resources : [proceedings of the Ninth International Conference on Computational Methods in Water Resources held at the University of Colorado at Denver, U.S.A., in June 1992] / ed.: T. F. Russell
Y1  - 1992
SN  - 185312169X
N1  - International Conference on Computational Methods in Water Resources ; (9, 1992, Denver, Colo.)
PB  - Computational Mechanics Publications [u.a.]
CY  - Southampton [u.a.]
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
T1  - QKan - Management of drainage system data with QGIS
JF  - Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings
Y1  - 2017
VL  - 17
IS  - Article 13
SP  - 95
EP  - 100
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
A1  - Arnold, Uwe
A1  - Rouvé, Gerhard
T1  - Measurement of transverse mixing using digital image acquisition
JF  - Mixing and transport in the environment : a memorial volume for Catherine M. Allen (1954-1991) / ed. by Keith J. Beven
Y1  - 1994
SN  - 0471941425
PB  - Wiley
CY  - Chichester [u.a.]
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
A1  - Arnold, Uwe
A1  - Rouvé, Gerhard
T1  - Combined Digital Image and Finite Element Analysis of Mixing in Compound Open Channel Flow / 	Arnold, U.; J. Höttges; G. Rouvé
JF  - Refined flow modelling and turbulence measurements : proceedings of the Third International Symposium Tokyo, Japan 26 - 28 July, 1988 / ed. by Y. Iwasa. Scientific Organizing Committee of the Third International Symposium on Refined Flow Modelling and Tur
Y1  - 1989
SN  - 4-946443-03-7
N1  - International Symposium on Refined Flow Modelling and Turbulence Measurements <3, 1988, T&#333;ky&#333;>
SP  - 569
EP  - 576
PB  - Universal Acad. Press
CY  - Tokyo
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
A1  - Arnold, Uwe
A1  - Rouvé, Gerhard
T1  - Profiles of Mixing Coefficient in Compound Open Channel
JF  - Flow modeling and turbulence measurements : [... a collection of lectures and papers presented at the Fourth International Symposium on Refined Flow Modelling and Turbulence Measurements held in Wuhan, People's Republic of China, on September 20-23, 1990]
Y1  - 1992
SN  - 1-56032-209-8
N1  - International Symposium on Refined Flow Modelling and Turbulence Measurements <4, 1990, Wuhan>
PB  - Hemisphere Publ. Corp.
CY  - Washington, DC [u.a.]
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
A1  - Feldhaus, R.
A1  - Brockhaus, T.
A1  - Rouvé, Gerhard
T1  - Finite Element Simulation of Flow and Pollution Transport applied to a Part of the River Rhine / Feldhaus, R.; J. Höttges, T. Brockhaus; G. Rouvé
JF  - 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
Y1  - 1992
N1  - International Conference on Hydraulic and Environmental Modelling of Coastal, Estuarine, and River Waters ; (2, 1992, Bradford)
PB  - Ashgate
CY  - Aldershot, Hants, UK [u.a.]
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
A1  - Ritterbach, E.
A1  - Els, H.
T1  - Optical Improvement of LDV-Measurement in Pipe Flow / Ritterbach, E.; J. Höttges; H. Els
JF  - 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
Y1  - 1987
SN  - 3540187561
PB  - Springer
CY  - Berlin [u.a.]
ER  - 
TY  - JOUR
A1  - Jochim, Haldor E.
T1  - A traffic resistance model of long-distance travel
JF  - Networks for mobility : 2nd international symposium, September 29 - October 1, 2004, Stuttgart, Germany ; proceedings ; abstracts and CD-ROM / [2nd International Symposium on Networks for Mobility]. FOVUS, Centre of Transportation Research, University of
Y1  - 2004
SN  - 3-89301-180-3
N1  - International Symposium on Networks for Mobility (2, 2004, Stuttgart)
PB  - FOVUS
CY  - Stuttgart
ER  - 
TY  - JOUR
A1  - Jochim, Haldor E.
T1  - Charging rail operators for delays – how not to do it
JF  - Networks for mobility : International Symposium, September 18 - 20, 2002, Stuttgart, Germany ; proceedings / University of Stuttgart, Centre of Transporation Research (FOVUS). W. Möhlenbrink ... (eds.)
Y1  - 2002
SN  - 3893010858
N1  - International Symposium ; (2002.09.18-20 : ; Stuttgart)
PB  - FOVUS
CY  - Stuttgart
ER  - 
TY  - JOUR
A1  - Kerpen, Nils B.
A1  - Bung, Daniel B.
A1  - Valero, Daniel
A1  - Schlurmann, Torsten
T1  - Energy dissipation within the wave run-up at stepped revetments
JF  - Journal of Ocean University of China
Y1  - 2017
U6  - http://dx.doi.org/10.1007/s11802-017-3355-z
SN  - 1993-5021
VL  - 16
IS  - 4
SP  - 649
EP  - 654
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Kerres, Karsten
A1  - Gredigk-Hoffmann, Sylvia
A1  - Jathe, Rüdiger
A1  - Orlik, Stefan
A1  - Sariyildiz, Mustafa
A1  - Schmidt, Torsten
A1  - Sympher, Klaus-Jochen
A1  - Uhlenbroch, Adrian
T1  - Future approaches for sewer system condition assessment
JF  - Water Practice & Technology
N2  - 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.
Y1  - 2020
U6  - http://dx.doi.org/10.2166/wpt.2020.027
SN  - 1751-231X
IS  - 15 (2)
SP  - 386
EP  - 393
PB  - IWA Publishing
CY  - London
ER  - 
TY  - JOUR
A1  - Kirsch, Ansgar
T1  - Experimental investigation of the face stability of shallow tunnels in sand
JF  - Acta Geotechnica
N2  - 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 Léca/Dormieux showed the best agreement to the measurements.
Y1  - 2010
U6  - http://dx.doi.org/10.1007/s11440-010-0110-7
SN  - 1861-1125
VL  - 5
IS  - 1
SP  - 43
EP  - 62
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Kirstein, Simon
A1  - Müller, Karsten
A1  - Walecki-Mingers, Mark
A1  - Deserno, Thomas M.
T1  - Robust adaptive flow line detection in sewer pipes
JF  - Automation in construction
N2  - As part of a novel approach to automatic sewer inspection, this paper presents a robust algorithm for automatic flow line detection. A large image repository is obtained from about 50,000 m sewers to represent the high variability of real world sewer systems. Automatic image processing combines Canny edge detection, Hough transform for straight lines and cost minimization using Dijkstra's shortest path algorithm. Assuming that flow lines are mostly smoothly connected horizontal structures, piecewise flow line delineation is reduced to a process of selecting adjacent line candidates. Costs are derived from the gap between adjacent candidates and their reliability. A single parameter α enables simple control of the algorithm. The detected flow line may precisely follow the segmented edges (α = 0.0) or minimize gaps at joints (α = 1.0). Both, manual and ground truth-based analysis indicate that α = 0.8 is optimal and independent of the sewer's material. The algorithm forms an essential step to further automation of sewer inspection.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.autcon.2011.05.009
SN  - 1872-7891 (E-Journal) ; 0926-5805 (Print)
IS  - 21
SP  - 24
EP  - 31
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Kolymbas, Dimitrios
A1  - Fellin, W.
A1  - Kirsch, Ansgar
T1  - Squeezing due to stress relaxation in foliated rock
JF  - International journal for numerical and analytical methods in geomechanics
Y1  - 2006
U6  - http://dx.doi.org/10.1002/nag.530
SN  - 1096-9853 (E-Journal); 0363-9061 (Print)
VL  - Vol. 30
IS  - Iss. 13
SP  - 1357
EP  - 1367
ER  - 
TY  - JOUR
A1  - Kramer, Matthias
A1  - Valero, Daniel
A1  - Chanson, Hubert
A1  - Bung, Daniel B.
T1  - Towards reliable turbulence estimations with phase-detection probes: an adaptive window cross-correlation technique
JF  - Experiments in Fluids
Y1  - 2019
U6  - http://dx.doi.org/10.1007/s00348-018-2650-9
SN  - 1432-1114
VL  - 60
EP  - Article number 2
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Kuhnhenne, Markus
A1  - Reger, Vitali
A1  - Pyschny, Dominik
A1  - Döring, Bernd
T1  - Influence of airtightness of steel sandwich panel joints on heat losses
JF  - E3S Web of Conferences 12th Nordic Symposium on Building Physics (NSB 2020)
N2  - 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.
Y1  - 2020
U6  - http://dx.doi.org/10.1051/e3sconf/202017205008
VL  - 172
IS  - Art. 05008
PB  - EDP Sciences
CY  - Les Ulis
ER  - 
TY  - JOUR
A1  - Leandro, J.
A1  - Bung, Daniel B.
A1  - Carvalho, R.
T1  - Measuring void fraction and velocity fields of a stepped spillway for skimming flow using non-intrusive methods
JF  - Experiments in fluids
Y1  - 2014
U6  - http://dx.doi.org/10.1007/s00348-014-1732-6
SN  - 0723-4864 (Print) ; 1432-1114 (Online)
IS  - 55
SP  - Art. 1732
PB  - Springer Nature
CY  - Heidelberg
ER  - 
TY  - JOUR
A1  - Lopes, Pedro
A1  - Leandro, Jorge
A1  - Carvalho, Rita F.
A1  - Bung, Daniel B.
T1  - Alternating skimming flow over a stepped spillway
JF  - Environmental Fluid Mechanics
Y1  - 2017
U6  - http://dx.doi.org/10.1007/s10652-016-9484-x
SN  - 1573-1510
VL  - 17
IS  - 2
SP  - 303
EP  - 322
PB  - Springer
CY  - Berlin
ER  -