TY - JOUR A1 - Vogt, C. A1 - Mottaghy, Darius A1 - Wolf, A. A1 - Rath, V. A1 - Pechnig, R. A1 - Clauser, C. T1 - Reducing temperature uncertainties by stochastic geothermal reservoir modelling JF - Geophysical Journal International N2 - Quantifying and minimizing uncertainty is vital for simulating technically and economically successful geothermal reservoirs. To this end, we apply a stochastic modelling sequence, a Monte Carlo study, based on (i) creating an ensemble of possible realizations of a reservoir model, (ii) forward simulation of fluid flow and heat transport, and (iii) constraining post-processing using observed state variables. To generate the ensemble, we use the stochastic algorithm of Sequential Gaussian Simulation and test its potential fitting rock properties, such as thermal conductivity and permeability, of a synthetic reference model and—performing a corresponding forward simulation—state variables such as temperature. The ensemble yields probability distributions of rock properties and state variables at any location inside the reservoir. In addition, we perform a constraining post-processing in order to minimize the uncertainty of the obtained distributions by conditioning the ensemble to observed state variables, in this case temperature. This constraining post-processing works particularly well on systems dominated by fluid flow. The stochastic modelling sequence is applied to a large, steady-state 3-D heat flow model of a reservoir in The Hague, Netherlands. The spatial thermal conductivity distribution is simulated stochastically based on available logging data. Errors of bottom-hole temperatures provide thresholds for the constraining technique performed afterwards. This reduce the temperature uncertainty for the proposed target location significantly from 25 to 12 K (full distribution width) in a depth of 2300 m. Assuming a Gaussian shape of the temperature distribution, the standard deviation is 1.8 K. To allow a more comprehensive approach to quantify uncertainty, we also implement the stochastic simulation of boundary conditions and demonstrate this for the basal specific heat flow in the reservoir of The Hague. As expected, this results in a larger distribution width and hence, a larger, but more realistic uncertainty estimate. However, applying the constraining post-processing the uncertainty is again reduced to the level of the post-processing without stochastic boundary simulation. Thus, constraining post-processing is a suitable tool for reducing uncertainty estimates by observed state variables. Y1 - 2010 U6 - https://doi.org/10.1111/j.1365-246X.2009.04498.x SN - 1365-246X VL - 181 IS - 1 SP - 321 EP - 333 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Rath, V. A1 - Mottaghy, Darius T1 - Smooth inversion for ground surface temperature histories: estimating the optimum regularization parameter by generalized cross-validation JF - Geophysical Journal International Y1 - 2007 U6 - https://doi.org/10.1111/j.1365-246X.2007.03587.x SN - 1365-246X VL - 171 IS - 3 SP - 1440 EP - 1448 ER - TY - JOUR A1 - Baier, C. A1 - Mottaghy, Darius A1 - Ziegler, M. A1 - Rath, V. T1 - Numerische Simulation des Gefrierprozesses bei der Baugrundvereisung im durchströmten Untergrund JF - Bauingenieur Y1 - 2008 SN - 0005-6650 VL - 83 IS - 2 SP - 49 EP - 60 ER - TY - JOUR A1 - Mottaghy, Darius A1 - Vosteen, Hans-Dieter A1 - Schellschmidt, Rüdiger T1 - Temperature dependence of the relationship of thermal diffusivity versus thermal conductivity for crystalline rocks JF - International Journal of Earth Sciences Y1 - 2008 U6 - https://doi.org/10.1007/s00531-007-0238-3 SN - 1437-3262 VL - 97 IS - 2 SP - 435 EP - 442 ER - TY - JOUR A1 - Mottaghy, Darius A1 - Pechnig, Renate T1 - Numerische 3D Modelle zur Temperaturvorhersage und Reservoirsimulationen JF - BBR - Fachmagazin für Brunnen- und Leitungsbau Y1 - 2009 VL - 60 IS - 10 SP - 44 EP - 51 ER - TY - JOUR A1 - Rath, V. A1 - Mottaghy, Darius T1 - Klimainformation aus dem Untergrund? JF - Geographische Rundschau Y1 - 2014 SN - 0016-7460 VL - 66 IS - 7-8 SP - 30 EP - 36 PB - Westermann CY - Braunschweig ER - TY - JOUR A1 - Vogt, C. A1 - Mottaghy, Darius A1 - Rath, V. A1 - Marquart, G. A1 - Dijkshoorn, L. A1 - Wolf, A. A1 - Clauser, C. T1 - Vertical variation in heat flow on the Kola Peninsula: palaeoclimate or fluid flow? JF - Geophysical Journal International N2 - Following earlier studies, we present forward and inverse simulations of heat and fluid transport of the upper crust using a local 3-D model of the Kola area. We provide best estimates for palaeotemperatures and permeabilities, their errors and their dependencies. Our results allow discriminating between the two mentioned processes to a certain extent, partly resolving the non-uniqueness of the problem. We find clear indications for a significant contribution of advective heat transport, which, in turn, imply only slightly lower ground surface temperatures during the last glacial maximum relative to the present value. These findings are consistent with the general background knowledge of (i) the fracture zones and the corresponding fluid movements in the bedrock and (ii) the glacial history of the Kola area. Y1 - 2014 U6 - https://doi.org/10.1093/gji/ggu282 SN - 1365-246X VL - 199 IS - 2 SP - 829 EP - 843 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Chen, Tao A1 - Clauser, Christoph A1 - Marquart, Gabriele A1 - Willbrand, Karen A1 - Mottaghy, Darius T1 - A new upscaling method for fractured porous media JF - Advances in Water Resources Y1 - 2015 U6 - https://doi.org/10.1016/j.advwatres.2015.03.009 SN - 0309-1708 N1 - Corrigendum 2019: https://doi.org/10.1016/j.advwatres.2019.01.004 VL - 80 SP - 60 EP - 68 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kürten, Sylvia A1 - Mottaghy, Darius A1 - Ziegler, Martin T1 - A new model for the description of the heat transfer for plane thermo-active geotechnical systems based on thermal resistances JF - Acta Geotechnica Y1 - 2015 U6 - https://doi.org/10.1007/s11440-014-0311-6 SN - 1861-1133 VL - 10 IS - 2 SP - 219 EP - 229 PB - Springer CY - Berlin ER - TY - JOUR A1 - Kürten, Sylvia A1 - Mottaghy, Darius A1 - Ziegler, Martin T1 - Design of plane energy geostructures based on laboratory tests and numerical modelling JF - Energy and Buildings Y1 - 2015 U6 - https://doi.org/10.1016/j.enbuild.2015.08.039 SN - 0378-7788 VL - 107 SP - 434 EP - 444 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kürten, Sylvia A1 - Mottaghy, Darius A1 - Ziegler, Martin T1 - Besonderheiten bei der Planung und Berechnung von oberflächennahen thermo-aktiven Bauteilen JF - Geotechnik Y1 - 2015 U6 - https://doi.org/10.1002/gete.201500002 SN - 2190-6653 VL - 38 IS - 2 SP - 107 EP - 119 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Srivastava, A. A1 - Lahiri, S. A1 - Maiti, M. A1 - Knolle, F. A1 - Hoyler, Friedrich A1 - Scherer, Ulrich W. A1 - Schnug, E. W. T1 - Study of naturally occurring radioactive material (NORM) in top soil of Punjab State from the North Western part of India JF - Journal of Radioanalytical and Nuclear Chemistry Y1 - 2014 U6 - https://doi.org/0.1007/s10967-014-3450-1 SN - 1588-2780 (E-Journal); 0022-4081 (Print); 0134-0719 (Print); 0236-5731 (Print); 1417-2097 (Print) VL - 2014 IS - 302 SP - 1049 EP - 1052 PB - Springer Nature CY - Basel ER - TY - JOUR A1 - Marx, Ulrich A1 - Schenk, Friedrich A1 - Behrens, Jan A1 - Meyr, Ulrike A1 - Wanek, Paul A1 - Zang, Werner A1 - Schmitt, Robert A1 - Brüstle, Oliver A1 - Zenke, Martin A1 - Klocke, Fritz T1 - Automatic production of induced pluripotent stem cells JF - Procedia CIRP : First CIRP Conference on BioManufacturing Y1 - 2013 SN - 2212-8271 VL - Vol. 5 SP - 2 EP - 6 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Borchert, Jörg A1 - Hasenbeck, Marc A1 - Jungbluth, Christian A1 - Schemm, Ralf T1 - Bewertung und Steuerung von Gasspeichern bzw. Gasspeicherscheiben JF - Zeitschrift für Energiewirtschaft N2 - In diesem Artikel werden zunächst einleitend der Gasmarkt Deutschland und der sich daraus ergebende Speicherbedarf skizziert. Folgend wird auf verschiedene Speichernutzen aus betriebswirtschaftlicher Perspektive eingegangen und die in diesem Artikel vorgestellten Bewertungsverfahren einleitend beschrieben. In diesem Artikel werden stochastische Optimierungsmethoden aufgegriffen, die sowohl eine Bewertung der Speicher gegenüber einem Spotpreis, als auch gegenüber einer gesamten Forwardcurve ermöglichen. Hierzu werden zunächst Modelle zur Beschreibung der Marktpreise vorgestellt und anhand empirischer Daten kalibriert. Dann wird eine beispielhafte Speicherscheibe zunächst auf Basis der LeastSquareMonteCarloTechnik gegenüber dem stochastischen mehrfaktoriellen Spotpreismodell bewertet. Hieran schließt sich die Vorstellung der Bewertung sowie des Hedgings gegenüber der Forwardcurve an. Abschließend erfolgt eine vergleichende Gegenüberstellung beider Verfahren. Y1 - 2009 U6 - https://doi.org/10.1007/s12398-009-0033-x SN - 1866-2765 VL - 33 IS - 4 SP - 279 EP - 293 PB - Springer CY - Berlin ER - TY - JOUR A1 - Borchert, Jörg A1 - Hasenbeck, Marc T1 - Bewertung und Steuerung von Kraftwerksscheiben JF - Zeitschrift für Energiewirtschaft Y1 - 2009 U6 - https://doi.org/10.1007/s12398-009-0014-0 SN - 1866-2765 VL - 33 IS - 2 SP - 115 EP - 126 PB - Vieweg CY - Wiesbaden ER - TY - JOUR A1 - Borchert, Jörg A1 - Schemm, R. T1 - Einsatz der Portfoliotheorie im Asset Allokations-Prozess am Beispiel eines fiktiven Anlageraumes von Windkraftstandorten JF - Zeitschrift für Energiewirtschaft Y1 - 2007 SN - 0343-5377 VL - 31 IS - 4 SP - 311 ER - TY - JOUR A1 - Jungbluth, Christian A1 - Borchert, Jörg T1 - Möglichkeiten der Strompreisbeeinflussung im oligopolistischen Markt JF - ZNER Zeitschrift für Neues Energierecht Y1 - 2008 IS - 4 SP - 314 EP - 323 ER - TY - JOUR A1 - Walter, G. A1 - Borchert, Jörg T1 - Der Einsatz von Realoptionen in der Elektrizitätswirtschaft JF - M & A Review Y1 - 2002 SN - 1616-0878 IS - 4 SP - 198 ER - TY - JOUR A1 - Kuperjans, Isabel A1 - Weitzel, J. T1 - Energiedesign 2020 : Sichere Strom- und Wärmeversorgung für die Industrie JF - TAB: das Fachmedium der TGA-Branche Y1 - 2015 SN - 0341-2032 IS - 3 SP - 105 EP - 107 PB - Bauverlag CY - Gütersloh ER - TY - JOUR A1 - Edip, K. A1 - Sesov, V. A1 - Butenweg, Christoph A1 - Bojadjieva, J. T1 - Development of coupled numerical model for simulation of multiphase soil JF - Computers and Geotechnics N2 - In this paper, a coupled multiphase model considering both non-linearities of water retention curves and solid state modeling is proposed. The solid displacements and the pressures of both water and air phases are unknowns of the proposed model. The finite element method is used to solve the governing differential equations. The proposed method is demonstrated through simulation of seepage test and partially consolidation problem. Then, implementation of the model is done by using hypoplasticity for the solid phase and analyzing the fully saturated triaxial experiments. In integration of the constitutive law error controlling is improved and comparisons done accordingly. In this work, the advantages and limitations of the numerical model are discussed. Y1 - 2018 U6 - https://doi.org/10.1016/j.compgeo.2017.08.016 SN - 0266-352X VL - 96 SP - 118 EP - 131 PB - Elsevier CY - Amsterdam ER -