TY - CHAP A1 - Bung, Daniel B. A1 - Valero, Daniel ED - Crookston, B. ED - Tullis, B. T1 - Application of the optical flow method to velocity determination in hydraulic structure models BT - Session 11: Fish passage and shiplocks T2 - Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016 Y1 - 2016 SN - 978-1-884575-75-4 U6 - http://dx.doi.org/10.15142/T3150628160853 SP - 223 EP - 232 ER - TY - CHAP A1 - Bung, Daniel B. A1 - Valero, Daniel ED - Dewals, Benjamin T1 - Image processing techniques for velocity estimation in highly aerated flows: bubble image velocimetry vs. optical flow T2 - Sustainable Hydraulics in the Era of Global Change : Proceedings of the 4th IAHR Europe Congress (Liege, Belgium, 27-29 July 2016) Y1 - 2016 SN - 978-1-138-02977-4 SN - 978-1-4987-8149-7 (eBook) U6 - http://dx.doi.org/10.1201/b21902-31 SP - 151 EP - 157 PB - CRC Press ER - TY - CHAP A1 - Bung, Daniel B. A1 - Valero, Daniel T1 - FlowCV - An open-source toolbox for computer vision applications in turbulent flows T2 - Proceedings of the 37th IAHR World Congress August 13 – 18, 2017, Kuala Lumpur, Malaysia Y1 - 2017 SN - 2521-716X SP - 5356 EP - 5365 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 - CHAP A1 - Bung, Daniel B. A1 - Tullis, Blake T1 - Hydraulic Structures - ISHS2018 in Perspective T2 - 7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May Y1 - 2018 SN - 978-0-692-13277-7 U6 - http://dx.doi.org/10.15142/T3WH2B ER - TY - CHAP A1 - Bung, Daniel B. A1 - Sun, Q. A1 - Meireles, I. A1 - Matos, J. A1 - Viseu, T. T1 - USBR type III stilling basin performance for steep stepped spillways T2 - Hydraulic structures into the 21st century : 4th IAHR International Symposium on Hydraulic Structures : 9.-11.2.2012, Porto Y1 - 2012 SN - 978-989-8509-01-7 ER - TY - CHAP A1 - Bung, Daniel B. A1 - Schlenkhoff, Andreas A1 - Oertel, M. T1 - Self-aerated skimming flow on embankment stepped spillways T2 - Water engineering for sustainable environment : 33rd IAHR congress ; 9 - 14 August 2009, Vancouver, British Columbia, Canada Y1 - 2009 SN - 9789078046080 SP - 1 CD-ROM ER - TY - CHAP A1 - Bung, Daniel B. A1 - Schlenkhoff, Andreas T1 - Self-aerated skimming flow on embankment stepped spillways : the effect of additional micro-roughness on energy dissipation and oxygen transfer T2 - Proceedings from first IAHR European congress : May 2010, Edinburgh Y1 - 2010 SN - 9780956595102 SP - Artikelkennnummer HSIIId PB - Heriot-Watt University, School of the Built Environment CY - Edinburgh ER - TY - CHAP A1 - Bung, Daniel B. A1 - Schlenkhoff, Andreas T1 - Selbstbelüftete Gerinneströmungen auf Treppenschussrinnen T2 - Talsperren im Wandel : 15. Deutsches Talsperrensymposium ; Beiträge zur Tagung am 14. bis 16. April 2010 im Eurogress Aachen Y1 - 2010 SN - 978-3-8322-9043-6 SP - 39 EP - 47 ER - TY - CHAP A1 - Bung, Daniel B. A1 - Schlenkhoff, Andreas ED - Pagliara, Stefano T1 - Optimization of the reaeration potential on embankment stepped spillways in skimming flow regime T2 - Hydraulic structures : proceedings of the second International Junior Researcher and Engineer Workshop on Hydraulic Structures, Pisa, Italy, 30 July-1 August 2008 Y1 - 2008 SN - 978-88-8492-568-8 SP - 97 EP - 106 ER - TY - CHAP A1 - Bung, Daniel B. A1 - Pagliara, S. T1 - Proceedings of the International Workshop on Hydraulic Design of Low-Head Structures : Aachen, Germany, February, 20-22, 2013 / D. Bung ; S. Pagliara (eds.) Y1 - 2013 SN - 978-3-939230-04-5 PB - Bundesanst. für Wasserbau CY - Karlsruhe ER - TY - CHAP A1 - Bung, Daniel B. A1 - Oertel, Mario T1 - Manipulation of non-aerated cavity flow on a stepped spillway model T2 - 3rd European IAHR Congress : April 14 – 16, 2014, Porto Y1 - 2014 PB - Univ. of Porto CY - Porto ER - TY - CHAP A1 - Bung, Daniel B. A1 - Oertel, Mario T1 - Wave breaking over a submerged horizontal plate: Optical Flow, LES and RANS T2 - E-proceedings of the 38th IAHR World Congress September 1-6, 2019, Panama City, Panama Y1 - 2019 U6 - http://dx.doi.org/10.3850/38WC092019-0509 SP - 3690 EP - 3698 ER - TY - CHAP A1 - Bung, Daniel B. A1 - Oertel, M. A1 - Schlenkhoff, A. A1 - Schlurmann, Torsten ED - Obrusnik, Ivan T1 - Flash flood awareness and prevention in Germany T2 - Early warning for flash floods : international workshop, Praha 2011 : workshop proceedings Y1 - 2010 SN - 978-80-86690-91-9 SP - 34 EP - 40 ER - TY - CHAP A1 - Bung, Daniel B. A1 - Hildebrandt, Arndt A1 - Oertel, Mario A1 - Schlenkhoff, Andreas A1 - Schlurmann, Torsten ED - McKee Smith, Jane T1 - Bore propagation over a submerged horizontal plate by physical and numerical simulation T2 - Coastal engineering 2008 : proceedings of the 31st international conference; Hamburg, Germany, 31 August - 5 September 2008 ; Vol. 4 Y1 - 2008 SN - 9814277401 ; 9789814277402 SP - 3542 EP - 3553 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. 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 - CHAP A1 - Bung, Daniel B. T1 - Non-intrusive measuring of air-water flow properties in self-aerated stepped spillway flow T2 - Balance and uncertainty - water in a changing world : proceedings of the 34th IAHR world congress ; 33rd Hydrology and Water Resources Symposium ; 10th Conference on Hydraulics in Water Engineering ; 26 June - 1 July 2011, Brisbane, Australia Y1 - 2011 SN - 978-0-85825-868-6 SP - 2380 EP - 2387 ER - TY - JOUR A1 - Bung, Daniel B. T1 - Fließcharakteristik und Sauerstoffeintrag bei selbstbelüfteten Gerinneströmungen auf Kaskaden mit gemäßigter Neigung JF - Österreichische Wasser- und Abfallwirtschaft Y1 - 2011 SN - 1613-7566 (E-Journal); 0945-358X (Print) VL - Vol. 63 IS - Iss. 3-4 SP - 76 EP - 81 PB - Springer CY - Berlin ER - TY - CHAP A1 - Bung, Daniel B. ED - Theobald, S. T1 - Optimierung des potentiellen Sauerstoffeintrags auf Treppenschussrinnen mit gemäßigter Neigung T2 - 9. JuWi-Treffen : Beiträge zum Treffen junger Wissenschaftlerinnen und junger Wissenschaftler deutschsprachiger Wasserbauinstitute Y1 - 2009 SP - 73 EP - 78 PB - Universität Kassel CY - Kassel ER - TY - CHAP A1 - Bung, Daniel B. T1 - A comparative study of self-aerated stepped spillway and smooth invert chute flow: the effect of step-induced macro roughness T2 - 5th Chinese-German Joint Symposium on Hydraulic and Ocean Engineering : CG JOINT 2010 Y1 - 2010 SN - 978-7-5618-3671-2 SP - 451 EP - 456 PB - Univ. Press CY - Tianjin ER - TY - CHAP A1 - Bung, Daniel B. T1 - Sensitivity of phase detection techniques in aerated chute flows to hydraulic design parameters T2 - 2nd European IAHR congress : 27. - 29. June 2012, München Y1 - 2012 SN - 978-3-943683-03-5 SP - Artikelkennnummer: B15 PB - Lehrstuhl u. Versuchsanst. für Wasserbau u. Wasserwirtschaft d. TU München CY - München ER - TY - CHAP A1 - Bung, Daniel B. T1 - Air-water surface roughness in self-aerated stepped spillway flows T2 - 35th IAHR world congress : 8.-13.9.2013, Chengdu, China Y1 - 2013 SP - Artikelkennnummer: A11045 PB - Tsinghua Univ. Press CY - Beijing ER - TY - THES A1 - Bung, Daniel B. T1 - Zur selbstbelüfteten Gerinneströmung auf Kaskaden mit gemäßigter Neigung. (Bericht / Fachbereich Bautechnik, Lehr- und Forschungsgebiet Wasserbau und Wasserwirtschaft, Bergische Universität Gesamthochschule Wuppertal ; Bd. 16) Y1 - 2009 SN - 978-3-8322-8382-7 N1 - Zugl.: Wuppertal, Univ., Diss., 2009 PB - Shaker CY - Aachen ER - TY - CHAP A1 - Bung, Daniel B. T1 - Observations on non-aerated flow and air entrainment on moderately sloped stepped spillways T2 - 7th Chinese-German Joint Symposium on Hydraulic and Ocean Engineering : 8. - 12. Sept. 2014, Hannover Y1 - 2014 N1 - Kennwortgeschützter Zugang. Passwort bei Prof. Bung, Fachbereich Bauingenieurwesen SP - 1 EP - 8 ER - TY - CHAP A1 - Bung, Daniel B. ED - Rowinski, Pawel T1 - Laboratory models of free-surface flows T2 - Rivers - physical, fluvial and environmental processes N2 - Hydraulic modeling is the classical approach to investigate and describe complex fluid motion. Many empirical formulas in the literature used for the hydraulic design of river training measures and structures have been developed using experimental data from the laboratory. Although computer capacities have increased to a high level which allows to run complex numerical simulations on standard workstation nowadays, non-standard design of structures may still raise the need to perform physical model investigations. These investigations deliver insight into details of flow patterns and the effect of varying boundary conditions. Data from hydraulic model tests may be used for calibration of numerical models as well. As the field of hydraulic modeling is very complex, this chapter intends to give a short overview on capacities and limits of hydraulic modeling in regard to river flows and hydraulic structures only. The reader shall get a first idea of modeling principles and basic considerations. More detailed information can be found in the references. KW - Physical modeling KW - Similitude KW - Open channels KW - Hydraulic structures Y1 - 2015 SN - 978-3-319-17718-2 ; 978-3-319-17719-9 U6 - http://dx.doi.org/10.1007/978-3-319-17719-9_9 SP - 213 EP - 228 PB - Springer CY - Cham ER - TY - JOUR A1 - Breuer, M. A1 - Peterson, Leif Arne A1 - Uibel, Thomas T1 - Der Studiengang Holzingenieurwesen der Fachhochschule Aachen JF - Jahrbuch des Kreises Euskirchen 2014 Y1 - 2013 SP - 165 EP - 168 ER - TY - CHAP A1 - Bornebusch, Michael T1 - Hydraulische und hydrologische Modellsimulation als Planungswerkzeug für Hochwasser-Schutz-Massnahmen N2 - In: Alfha.net / Sektion Bauingenieurwesen: 1. [Erster] Erfahrungsaustausch : Absolventen des Fachbereichs Bauingenieurwesens berichten. 13. Oktober 2006. S. 25-27. Zusammenfassung des Vortrags. KW - Hochwasserschutz KW - Niederschlag-Abfluss-Modelle KW - N-A-Modelle KW - Gewässerausbau Y1 - 2006 ER - TY - BOOK A1 - Bleninger, T. A1 - Brenda, M. A1 - Bung, Daniel B. A1 - Hengl, M. A1 - Schmid, B.H. A1 - Schneider, E. A1 - Sonnenburg, A. A1 - Stoschek, O. T1 - DWA-Regelwerk M 544-1 : Merkblatt: Ausbreitungsprobleme von Einleitungen - Prozesse, Methoden und Modelle - Teil 1: Anwendungsgrundlagen, Schätzformeln und eindimensionale Modelle Y1 - 2016 SN - 978-3-88721-280-3 CY - Hennef ER - TY - BOOK A1 - Bleninger, T. A1 - Brenda, M. A1 - Bung, Daniel B. A1 - Hengl, M. A1 - Schmid, B.H. A1 - Schneider, E. A1 - Sonnenburg, A. A1 - Stoschek, O. T1 - DWA-Regelwerk M 544-2 : Merkblatt: Ausbreitungsprobleme von Einleitungen - Prozesse, Methoden und Modelle - Teil 2: Mehrdimensionale Modelle Y1 - 2016 SN - 978-3-88721-281-0 CY - Hennef ER - TY - JOUR A1 - Blecken, Udo A1 - Holthaus-Sellheier, Ursula T1 - Quantitative Prognoseverfahren für den Büroimmobilienmarkt, Tl.1 JF - GuG : Grundstücksmarkt und Grundstückswert Y1 - 2011 SN - 0938-0175 VL - 21 IS - 1 SP - 30 EP - 39 PB - Werner CY - Köln ER - TY - JOUR A1 - Blecken, Udo A1 - Holthaus-Sellheier, Ursula T1 - Quantitative Prognoseverfahren für den Büroimmobilienmarkt. Tl. 2 JF - GuG : Grundstücksmarkt und Grundstückswert Y1 - 2011 SN - 0938-0175 N1 - (Fortsetzung des Beitrags aus GuG 1/2011, 30) VL - 21 IS - 3 SP - 156 EP - 163 PB - Werner CY - Köln ER - TY - JOUR A1 - Blecken, Udo A1 - Holthaus-Sellheier, Ursula T1 - Quantitative Prognoseverfahren für Mietpreise von Bueroimmobilien am Beispiel Düsseldorf JF - GuG : Grundstücksmarkt und Grundstückswert Y1 - 2012 SN - 0938-0175 VL - 23 IS - 1 SP - 12 EP - 21 PB - Werner CY - Köln ER - TY - CHAP A1 - Blaß, Hans Joachim A1 - Uibel, Thomas ED - Kuhlmann, U. T1 - Tragfähigkeit von stiftförmigen Verbindungsmitteln in Brettsperrholz T2 - Forschungskolloquium, Holzbau Forschung und Praxis, Stuttgart 2006. Tagungsband Y1 - 2006 SP - 167 EP - 174 PB - Universität CY - Stuttgart ER - TY - CHAP A1 - Blaß, Hans Joachim A1 - Uibel, Thomas ED - Moosbrugger, Thomas T1 - Forschung an der Universität Karlsruhe - Stiftförmige Verbindungsmittel in Brettsperrholz T2 - Brettsperrholz : ein Blick auf Forschung und Entwicklung ; 5. Grazer Holzbau-Fachtagung ; 5. GraHFT' 06; Tagungsband ; Graz, am 29. September 2006 / Institut für Holzbau und Holztechnologie ... [Tagungsband: Thomas Moosbrugger ...] Y1 - 2006 SN - 3-902020-32-6 N1 - Grazer Holzbau-Fachtagung ; (5 ; 2006.09.29 ; Graz); Institut für Holzbau und Holztechnologie SP - I-6 EP - I-16 ER - TY - BOOK A1 - Blaß, Hans Joachim A1 - Uibel, Thomas T1 - Tragfähigkeit von stiftförmigen Verbindungsmitteln in Brettsperrholz Y1 - 2007 SN - 978-3-86644-129-3 N1 - Karlsruher Berichte zum Ingenieurholzbau ; 8 PB - Universität CY - Karlsruhe ER - TY - JOUR A1 - Blaß, Hans Joachim A1 - Uibel, Thomas T1 - Bemessungsvorschläge für Verbindungsmittel in Brettsperrholz JF - Bauen mit Holz Y1 - 2009 SN - 0005-6545 N1 - gedruckt in der Bereichsbibliothek Bayernallee unter der Signatur 13 Z 117 VL - 111 IS - 2 SP - 46 EP - 53 PB - Rudolf Müller CY - Köln ER - TY - BOOK A1 - Blaß, Hans Joachim A1 - Uibel, Thomas T1 - Spaltversagen von Holz in Verbindungen : ein Rechenmodell für die Rissbildung beim Eindrehen von Holzschrauben Y1 - 2009 SN - 978-3-86644-312-9 PB - Universitäts-Verl. CY - Karlsruhe ER - TY - BOOK A1 - Blaß, Hans Joachim A1 - Uibel, Thomas ED - Schickhofer, Gerhard T1 - BSPhandbuch : Holz-Massivbauweise in Brettsperrholz; Nachweise auf Basis des neuen europäischen Normenkonzepts Y1 - 2009 SN - 978-3-85125-076-3 PB - Verl. der Techn. Univ. CY - Graz ER - TY - BOOK A1 - Blaß, Hans Joachim A1 - Uibel, Thomas T1 - Rechnerische Nachweise für das Spaltversagen von Holz in Haupt-Nebenträger-Anschlüssen. Teil 1: Entwicklung eines Rechenmodells Y1 - 2011 SN - 978-3-8167-8586-6 N1 - Bauforschung : T ; 3263,1 PB - Fraunhofer IRB CY - Stuttgart ER - TY - BOOK A1 - Blaß, Hans Joachim A1 - Uibel, Thomas T1 - Rechnerische Nachweise für das Spaltversagen von Holz in Haupt-Nebenträger-Anschlüssen. Teil 2: Überprüfung und Erweiterung des Rechenmodells Y1 - 2011 SN - 978-3-8167-8588-0 N1 - Bauforschung : T ; 3263,2 PB - Fraunhofer IRB CY - Stuttgart ER - TY - BOOK A1 - Blaß, Hans Joachim A1 - Uibel, Thomas T1 - Spaltversagen von Holz in mehrreihigen Verbindungen : Erweiterung des Rechen-modells für die Rissbildung beim Eindrehen von Holzschrauben Y1 - 2012 SN - 978-3-86644-852-0 N1 - Karlsruher Berichte zum Ingenieurholzbau ; Band 21 PB - KIT Scientific Publishing CY - Karlsruhe ER - TY - BOOK A1 - Blaß, Hans Joachim A1 - Bejtka, Ireneusz A1 - Uibel, Thomas T1 - Tragfähigkeit von Verbindungen mit selbstbohrenden Holzschrauben mit Vollgewinde Y1 - 2006 SN - 3-86644-034-0 PB - Universitäts-Verl. CY - Karlsruhe ER - TY - CHAP A1 - Blanke, Tobias A1 - Schmidt, Katharina S. A1 - Göttsche, Joachim A1 - Döring, Bernd A1 - Frisch, Jérôme A1 - van Treeck, Christoph ED - Weidlich, Anke ED - Neumann, Dirk ED - Gust, Gunther ED - Staudt, Philipp ED - Schäfer, Mirko T1 - Time series aggregation for energy system design: review and extension of modelling seasonal storages T2 - Energy Informatics N2 - Using optimization to design a renewable energy system has become a computationally demanding task as the high temporal fluctuations of demand and supply arise within the considered time series. The aggregation of typical operation periods has become a popular method to reduce effort. These operation periods are modelled independently and cannot interact in most cases. Consequently, seasonal storage is not reproducible. This inability can lead to a significant error, especially for energy systems with a high share of fluctuating renewable energy. The previous paper, “Time series aggregation for energy system design: Modeling seasonal storage”, has developed a seasonal storage model to address this issue. Simultaneously, the paper “Optimal design of multi-energy systems with seasonal storage” has developed a different approach. This paper aims to review these models and extend the first model. The extension is a mathematical reformulation to decrease the number of variables and constraints. Furthermore, it aims to reduce the calculation time while achieving the same results. KW - Energy system KW - Renewable energy KW - Mixed integer linear programming (MILP) KW - Typical periods KW - Time-series aggregation Y1 - 2022 U6 - http://dx.doi.org/10.1186/s42162-022-00208-5 SN - 2520-8942 N1 - Proceedings of the 11th DACH+ Conference on Energy Informatics, 15-16 September 2022, Freiburg, Germany. VL - 5 IS - 1, Article number: 17 SP - 1 EP - 14 PB - Springer Nature ER - TY - JOUR A1 - Blanke, Tobias A1 - Reger, Vitali A1 - Döring, Bernd A1 - Göttsche, Joachim A1 - Kuhnhenne, Markus T1 - Koaxiale Stahlenergiepfähle JF - Stahlbau N2 - Ein entscheidender Teil der Energiewende ist die Wärmewende im Gebäudesektor. Ein Schlüsselelement sind hier Wärmepumpen. Diese benötigen eine Wärmequelle, der sie Energie entziehen können, um sie auf ein höheres Temperaturniveau zu transformieren. Diese Wärmequelle kann bspw. das Erdreich sein, dessen Wärme durch Erdsonden erschlossen werden kann. In diesem Beitrag werden in Stahlpfähle integrierte Koaxialsonden mit dem Stand der Technik von Erdsonden gleichen Durchmessers bezüglich ihrer thermischen Leistungsmerkmale verglichen. Die Stahlenergiepfähle bieten neben der Wärmegewinnung weitere Vorteile, da sie auch eine statische Funktion übernehmen und rückstandsfrei zurückgebaut werden können. Es werden analytische und numerische Berechnungen vorgestellt, um die thermischen Potenziale beider Systeme zu vergleichen. Außerdem wird ein Testaufbau gezeigt, bei dem Stahlenergiepfähle in zwei verschiedenen Längen mit vorhandenen gängigen Erdsonden verglichen werden können. Die Berechnungen zeigen einen deutlichen thermischen Mehrertrag zwischen 26 % und 148 % der Stahlenergiepfähle gegenüber dem Stand der Technik abhängig vom Erdreich. Die Messergebnisse zeigen einen thermischen Mehrertrag von über 100 %. Es lässt sich also signifikante Erdsondenlänge einsparen. Dabei ist zu beachten, dass sich damit der thermisch genutzte Bereich des Erdreichs reduziert, wodurch die thermische Regeneration und/oder das Langzeitverhalten des Erdreichs an Bedeutung gewinnt. Y1 - 2021 VL - 90. 2021 IS - 6 SP - 417 EP - 424 PB - Wiley CY - Weinheim 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 - Biener, Ernst A1 - Wernhoff, T. A1 - Bökers, H. A1 - Sasse, T. T1 - Bau und 7-jähriger Betrieb eines Dichtungskontrollsystems sowie Durchführung von Bewässerungsmaßnahmen auf der Deponie Wesuwe / Wernhoff, T. ; Bökers, H. ; Biener, E. ; Sasse, T. JF - Tagungsband / 3. Praxistagung Deponie 2008 : Zwischenlager - Deponien - Nachsorge ; 2. und 3. Dezember 2008 / Wasteconsult International. Matthias Kühle-Weidemeier (Hrsg.) Y1 - 2008 SN - 978-3-86727-801-0 N1 - Praxistagung Deponie <3, 2008, Hannover> SP - 157 EP - 174 PB - Cuvillier CY - Göttingen 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 -