@article{ValeroBung2018, author = {Valero, Daniel and Bung, Daniel B.}, title = {Reformulating self-aeration in hydraulic structures: Turbulent growth of free surface perturbations leading to air entrainment}, series = {International Journal of Multiphase Flow}, volume = {100}, journal = {International Journal of Multiphase Flow}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0301-9322}, doi = {10.1016/j.ijmultiphaseflow.2017.12.011}, pages = {127 -- 142}, year = {2018}, abstract = {A new formulation for the prediction of free surface dynamics related to the turbulence occurring nearby is proposed. This formulation, altogether with a breakup criterion, can be used to compute the inception of self-aeration in high velocity flows like those occurring in hydraulic structures. Assuming a simple perturbation geometry, a kinematic and a non-linear momentum-based dynamic equation are formulated and forces acting on a control volume are approximated. Limiting steepness is proposed as an adequate breakup criterion. Role of the velocity fluctuations normal to the free surface is shown to be the main turbulence quantity related to self-aeration and the role of the scales contained in the turbulence spectrum are depicted. Surface tension force is integrated accounting for large displacements by using differential geometry for the curvature estimation. Gravity and pressure effects are also contemplated in the proposed formulation. The obtained equations can be numerically integrated for each wavelength, hence resulting in different growth rates and allowing computation of the free surface roughness wavelength distribution. Application to a prototype scale spillway (at the Aviemore dam) revealed that most unstable wavelength was close to the Taylor lengthscale. Amplitude distributions have been also obtained observing different scaling for perturbations stabilized by gravity or surface tension. The proposed theoretical framework represents a new conceptualization of self-aeration which explains the characteristic rough surface at the non-aerated region as well as other previous experimental observations which remained unresolved for several decades.}, language = {en} } @article{ValeroBung2017, author = {Valero, Daniel and Bung, Daniel B.}, 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{ValeroBung2018, author = {Valero, Daniel and Bung, Daniel B.}, 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{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{UibelBlass2013, author = {Uibel, Thomas and Blaß, Hans-Joachim}, title = {Joints with Dowel Type Fasteners in CLT structures}, series = {Focus solid timber solutions : European Conference on Cross Laminated Timber (CLT); May 21-22, 2013, Graz University of Technology, Austria}, booktitle = {Focus solid timber solutions : European Conference on Cross Laminated Timber (CLT); May 21-22, 2013, Graz University of Technology, Austria}, organization = {European Conference on Cross Laminated Timber <2013, Graz>}, isbn = {978-1-85790-181-8 ; 1-85790-181-9}, pages = {119 -- 134}, year = {2013}, language = {en} } @inproceedings{UibelBlass2006, author = {Uibel, Thomas and Blaß, Hans Joachim}, title = {Load Carrying Capacity of Joints with Dowel Type Fasteners in Solid Wood Panels}, series = {Proceedings. CIB-W18 Meeting 2006, Florence, Italy 2006}, booktitle = {Proceedings. CIB-W18 Meeting 2006, Florence, Italy 2006}, issn = {0945-6996}, pages = {1 -- 10}, year = {2006}, language = {en} } @inproceedings{UibelBlass2007, author = {Uibel, Thomas and Blaß, Hans Joachim}, title = {Edge Joints with Dowel Type Fasteners in Cross Laminated Timber}, series = {Proceedings. CIB-W18 Meeting 2007, Bled, Slovenia 2007}, booktitle = {Proceedings. CIB-W18 Meeting 2007, Bled, Slovenia 2007}, issn = {0945-6996}, pages = {1 -- 11}, year = {2007}, language = {en} } @inproceedings{UibelBlass2010, author = {Uibel, Thomas and Blaß, Hans Joachim}, title = {A new method to determine suitable spacings and distances for self-tapping screws}, series = {Meeting ... / International Council for Research and Innovation in Building and Construction, Working Commission W18 - Timber Structures}, volume = {43}, booktitle = {Meeting ... / International Council for Research and Innovation in Building and Construction, Working Commission W18 - Timber Structures}, publisher = {Lehrstuhl f{\"u}r Ingenieurholzbau und Baukonstruktionen}, address = {Karlsruhe}, issn = {1864-1784}, year = {2010}, abstract = {The determination of spacing, edge and end distance requirements for self-tapping screws requires numerous and comprehensive insertion tests. Yet the results of such tests cannot be transferred to other types of screws or even to screws of different diameter because of differences in shape or geometry. To reduce the effort of insertion tests a new method was developed which allows the estimation of required spacings, distances and timber thickness.}, 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} } @inproceedings{StepkesZimmermannMuelleretal.2007, author = {Stepkes, Hermann and Zimmermann, J. and M{\"u}ller, Karsten and Siekmann, Marko and Pinnekamp, Josef}, title = {Economical rehabilitation of sewer systems by ground penetration radar investigations}, series = {Strategic asset management of water supply and wastewater infrastructures : invited papers from the 2nd IWA Leading Edge Conference on Strategic Asset Management (LESAM), Lisbon, October [17 - 19] 2007 / ed. by Helene Alegre and Maria do C{\´e}u Almeida}, booktitle = {Strategic asset management of water supply and wastewater infrastructures : invited papers from the 2nd IWA Leading Edge Conference on Strategic Asset Management (LESAM), Lisbon, October [17 - 19] 2007 / ed. by Helene Alegre and Maria do C{\´e}u Almeida}, publisher = {IWA Publ.}, address = {London}, isbn = {9781843391869}, pages = {501 -- 520}, year = {2007}, language = {en} } @inproceedings{SpasovDoeringGriffin2007, author = {Spasov, Yulian and D{\"o}ring, Bernd and Griffin, Allan}, title = {Exploiting the thermal mass in an energy efficient building - a comparison exercise between IES Apache and TRNSYS models}, series = {Clima 2007 WellBeing Indoors: 9th Rehva World Congress, 10-14 June 2007, Helsinki, Finland : proceedings}, booktitle = {Clima 2007 WellBeing Indoors: 9th Rehva World Congress, 10-14 June 2007, Helsinki, Finland : proceedings}, address = {Helsinki}, isbn = {978-952-99898-2-9}, pages = {1 -- 7}, year = {2007}, language = {en} } @inproceedings{SiekmannMueller2011, author = {Siekmann, Thomas and M{\"u}ller, Karsten}, title = {Adaptive potential of the stormwater management in urban areas faced by the climate change}, series = {12th International Conference on Urban Drainage, Porto Alegre/Brazil, 11-16 September 2011}, booktitle = {12th International Conference on Urban Drainage, Porto Alegre/Brazil, 11-16 September 2011}, pages = {9 S.}, year = {2011}, language = {en} } @inproceedings{SchulzeBuxlohGrossUlbrich2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz and Ulbrich, Michelle}, title = {Digital planning using building information modelling and virtual reality: new approach for students' remote practical training under lockdown conditions in the course of smart building engineering}, series = {Proceedings of International Conference on Education in Mathematics, Science and Technology 2021}, booktitle = {Proceedings of International Conference on Education in Mathematics, Science and Technology 2021}, publisher = {ISTES Organization}, address = {San Antonio, TX}, isbn = {978-1-952092-17-6}, pages = {118 -- 123}, year = {2021}, abstract = {The worldwide Corona pandemic has severely restricted student projects in the higher semesters of engineering courses. In order not to delay the graduation, a new concept had to be developed for projects under lockdown conditions. Therefore, unused rooms at the university should be digitally recorded in order to develop a new usage concept as laboratory rooms. An inventory of the actual state of the rooms was done first by taking photos and listing up all flaws and peculiarities. After that, a digital site measuring was done with a 360° laser scanner and these recorded scans were linked to a coherent point cloud and transferred to a software for planning technical building services and supporting Building Information Modelling (BIM). In order to better illustrate the difference between the actual and target state, two virtual reality models were created for realistic demonstration. During the project, the students had to go through the entire digital planning phases. Technical specifications had to be complied with, as well as documentation, time planning and cost estimate. This project turned out to be an excellent alternative to on-site practical training under lockdown conditions and increased the students' motivation to deal with complex technical questions.}, language = {en} } @misc{SchulzeBuxlohGrossCheng2020, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz and Cheng, Kevin Toni}, title = {Development and manufacturing of an interactive three-dimensional phase diagram of carbon dioxide for teaching sessions in thermodynamics}, series = {Proceedings of the International Conference The Future of Education 2020}, journal = {Proceedings of the International Conference The Future of Education 2020}, year = {2020}, language = {en} } @inproceedings{SchulzeBuxlohGross2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz}, title = {Miniature urban farming plant: a complex educational "Toy" for engineering students}, series = {The Future of Education 11th Edition 2021}, booktitle = {The Future of Education 11th Edition 2021}, pages = {4 Seiten}, year = {2021}, abstract = {Urban farming is an innovative and sustainable way of food production and is becoming more and more important in smart city and quarter concepts. It also enables the production of certain foods in places where they usually dare not produced, such as production of fish or shrimps in large cities far away from the coast. Unfortunately, it is not always possible to show students such concepts and systems in real life as part of courses: visits of such industry plants are sometimes not possible because of distance or are permitted by the operator for hygienic reasons. In order to give the students the opportunity of getting into contact with such an urban farming system and its complex operation, an industrial urban farming plant was set up on a significantly smaller scale. Therefore, all needed technical components like water aeriation, biological and mechanical filtration or water circulation have been replaced either by aquarium components or by self-designed parts also using a 3D-printer. Students from different courses like mechanical engineering, smart building engineering, biology, electrical engineering, automation technology and civil engineering were involved in this project. This "miniature industrial plant" was also able to start operation and has now been running for two years successfully. Due to Corona pandemic, home office and remote online lectures, the automation of this miniature plant should be brought to a higher level in future for providing a good control over the system and water quality remotely. The aim of giving the student a chance to get to know the operation of an urban farming plant was very well achieved and the students had lots of fun in "playing" and learning with it in a realistic way.}, language = {en} } @inproceedings{SchulzeBuxlohGross2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz}, title = {Interdisciplinary Course Smart Building Engineering: A new approach of teaching freshmen in remote teamwork project under pandemic restrictions}, series = {New Perspectives in Science Education -International Conference (virtual event, 18-19 March 2021)}, booktitle = {New Perspectives in Science Education -International Conference (virtual event, 18-19 March 2021)}, publisher = {Filodiritto}, address = {Bologna}, pages = {4 Seiten}, year = {2021}, abstract = {In the context of the Corona pandemic and its impact on teaching like digital lectures and exercises a new concept especially for freshmen in demanding courses of Smart Building Engineering became necessary. As there were hardly any face-to-face events at the university, the new teaching concept should enable a good start into engineering studies under pandemic conditions anyway and should also replace the written exam at the end. The students should become active themselves in small teams instead of listening passively to a lecture broadcast online with almost no personal contact. For this purpose, a role play was developed in which the freshmen had to work out a complete solution to the realistic problem of designing, construction planning and implementing a small guesthouse. Each student of the team had to take a certain role like architect, site manager, BIM-manager, electrician and the technitian for HVAC installations. Technical specifications must be complied with, as well as documentation, time planning and cost estimate. The final project folder had to contain technical documents like circuit diagrams for electrical components, circuit diagrams for water and heating, design calculations and components lists. On the other hand construction schedule, construction implementation plan, documentation of the construction progress and minutes of meetings between the various trades had to be submitted as well. In addition to the project folder, a model of the construction project must also be created either as a handmade model or as a digital 3D-model using Computer-aided design (CAD) software. The first steps in the field of Building information modelling (BIM) had also been taken by creating a digital model of the building showing the current planning status in real time as a digital twin. This project turned out to be an excellent training of important student competencies like teamwork, communication skills, and self -organisation and also increased motivation to work on complex technical questions. The aim of giving the student a first impression on the challenges and solutions in building projects with many different technical trades and their points of view was very well achieved and should be continued in the future.}, language = {en} } @inproceedings{SchlurmannBung2012, author = {Schlurmann, Torsten and Bung, Daniel B.}, title = {Experimental investigation of flow-induced radial gate vibrations at Lower Subansiri dam}, series = {Sixth Chinese-German Joint Symposium on Hydraulic and Ocean Engineering : JOINT 2012 : 23.-29.9.2012, Keelung}, booktitle = {Sixth Chinese-German Joint Symposium on Hydraulic and Ocean Engineering : JOINT 2012 : 23.-29.9.2012, Keelung}, organization = {Chinese-German Joint Symposium on Hydraulic and Ocean Engineering <6, 2012, Keelung>}, pages = {7 -- 14}, year = {2012}, language = {en} } @inproceedings{SchlenkhoffBung2009, author = {Schlenkhoff, Andreas and Bung, Daniel B.}, title = {Prediction of oxygen transfer in self-aerated skimming flow on embankment stepped spillways}, series = {Water engineering for sustainable environment : 33rd IAHR congress ; 9 - 14 August 2009, Vancouver, British Columbia, Canada}, booktitle = {Water engineering for sustainable environment : 33rd IAHR congress ; 9 - 14 August 2009, Vancouver, British Columbia, Canada}, organization = {International Association for Hydraulic Engineering and Research}, isbn = {9789078046080}, pages = {1 CD-ROM}, year = {2009}, language = {en} } @techreport{SansomLawsonTuchoetal.2016, author = {Sansom, M. and Lawson, R.M. and Tucho, R. and Kendrick, C. and Ogden, R. and Resalati, S. and Garay, R. and D{\"o}ring, Bernd and Reger, V. and Gilbert, J. and Heikkinen, J. and Hemmila, K.}, title = {Building in active thermal mass into steel structures (BATIMASS) - EUR 28166EN}, publisher = {Publications Office of the European Union}, address = {Luxembourg}, organization = {European Commission}, isbn = {978-92-79-63176-4}, issn = {1831-9424}, doi = {10.2777/25999}, pages = {147 Seiten}, year = {2016}, abstract = {The main objective of the BATIMASS project was to address how the energy balance in relatively lightweight steel buildings can be improved by building in 'active thermal mass' (ATM) into the building fabric. This was achieved through concept design, dynamic thermal modelling and testing of a number of potentially viable systems and concepts. A significant programme of thermal simulation modelling was undertaken utilising the thermally equivalent slab (TES) concept to model the passive thermal capacity effect of profiled, composite metal floor decks. It is apparent from the modelling results that thermal mass is a highly complex phenomenon which is highly dependent upon building type, occupancy patterns, climate and many other aspects of the building design and servicing strategy. The ATM systems developed, both conceptually and for prototype testing, focussed on water-cooled composite slabs, the Cofradal floor system and the phase change material (PCM) Energain. In addition to laboratory testing of prototypes, whole building monitoring was undertaken at the Kubik building in Spain and the RWTH test building in Germany. Advanced thermal modelling was also undertaken to estimate the likely benefits of the ATM concept designs developed and for comparison with the test results. In addition to thermal testing, structural tests were conducted on composite floor specimens incorporating embedded water pipes. This Final Report presents the results of the activities carried out under this RFCS contract RFSR CT 2012 00033. The work carried out is reported in six major sections corresponding to the technical Work Packages of the project. Only summaries of the work carried out are provided in this report; all work undertaken is fully reported in the formal project deliverables.}, 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} }