TY  - CHAP
A1  - Hoffschmidt, Bernhard
T1  - Solarer Luftkollektor - Entwicklung und Optimierung von bestehenden Fassadenelementen
T2  - 15. Symposium Thermische Solarenergie : 27. bis 29. April 2005, Kloster Banz, Bad Staffelstein
Y1  - 2005
SN  - 3-934681-39-5
SP  - 106
EP  - 111
PB  - OTTI-Energie-Kolleg
CY  - Regensburg
ER  - 
TY  - CHAP
A1  - Hoffschmidt, Bernhard
T1  - Entwicklung eines modularen und effizienten Parabolrinnenkollektors
T2  - 15. Symposium Thermische Solarenergie : 27. bis 29. April 2005, Kloster Banz, Bad Staffelstein
Y1  - 2005
SN  - 3-934681-39-5
SP  - 158
EP  - 163
PB  - OTTI-Energie-Kolleg
CY  - Regensburg
ER  - 
TY  - CHAP
A1  - Schwarzer, Klemens
T1  - Solarthermisches Entsalzungssystem mit Wärmerückgewinnung - Erste Feldtestergebnisse
T2  - 16. Symposium Thermische Solarenergie : 17. bis 19. Mai 2006, Kloster Banz, Bad Staffelstein
Y1  - 2006
SN  - 3-934681-45-X
SP  - 173
EP  - 178
PB  - Ostbayer. Technologie-Transfer-Inst.
CY  - Regensburg
ER  - 
TY  - CHAP
A1  - Kroker, Jan
A1  - Hoffschmidt, Bernhard
A1  - Schwarzer, Klemens
A1  - Späte, Frank
T1  - PTC 1000 modular parabolic trough collector
T2  - Process heat collectors : state of the art within task 33/IV ; IEA SHC-Task 33 and SolarPACES-Task IV: Solar heat for industrial processes : Förderkennzeichen BMBF 0329273A / Solar Heating and Cooling Executive Committee of the International Energy Agency (IEA) ; ed. Werner Weiss
Y1  - 2008
SP  - 45
EP  - 46
PB  - AEE INTEC
CY  - Gleisdorf
ER  - 
TY  - CHAP
A1  - Schwarzer, Klemens
T1  - Desalination systems with renewable energies
T2  - DME Seminar Desalination and Renewable Energies : June 19 and 20 2008, Solar Institut Jülich / Deutsche Meerwasserentsalzung e.V.
Y1  - 2008
SN  - 978-3-86861-017-8
PB  - DME
CY  - Duisburg
ER  - 
TY  - CHAP
A1  - Hoffschmidt, Bernhard
T1  - Solar tower power plants
T2  - DME Seminar Desalination and Renewable Energies : June 19 and 20 2008, Solar Institut Jülich / Deutsche Meerwasserentsalzung e.V.
Y1  - 2008
SN  - 978-3-86861-017-8
PB  - DME
CY  - Duisbrug
ER  - 
TY  - CHAP
A1  - Sauerborn, Markus
A1  - Arshadi, S.
A1  - Rohrmoser, R.
T1  - Influence of clouds and aerosols to the haze of the sunshape
T2  - 30th ISES Biennial Solar World Congress 2011 : Kassel, Germany, 28 August - 2 September 2011. Vol. 5
Y1  - 2012
SP  - 3887
EP  - 3894
PB  - Curran
CY  - Red Hook, NY
ER  - 
TY  - CHAP
A1  - Hoffschmidt, Bernhard
A1  - Telle, R.
A1  - Sauerborn, Markus
A1  - Wagner, M.
T1  - Optical measurement system for high temperature absorbers
T2  - SolarPACES 2011 : concentrating solar power and chemical energy systems : 20 - 23 September, 2011, Granada, Spain
Y1  - 2011
CY  - Granada
ER  - 
TY  - CHAP
A1  - Hirsch, Tobias
A1  - Ahlbrink, Nils
A1  - Pitz-Paal, Robert
A1  - Teixeira Boura, Cristiano José
A1  - Hoffschmidt, Bernhard
A1  - Gall, Jan
A1  - Abel, Dirk
A1  - Nolte, Vera
A1  - Wirsum, Manfred
A1  - Andersson, Joel
A1  - Diehl, Moritz
T1  - Dynamic simulation of a solar tower system with open volumetric receiver - a review on the ViCERP project
T2  - SolarPACES 2011 : concentrating solar power and chemical energy systems : 20 - 23 September, 2011, Granada, Spain
Y1  - 2011
CY  - Granada
ER  - 
TY  - JOUR
A1  - Agrafiotis, Christos C.
A1  - Mavroidis, Ilias
A1  - Konstandopoulos, Athansios G.
A1  - Hoffschmidt, Bernhard
A1  - Stobbe, Per
A1  - Romero, Manuel
A1  - Fernandez-Quero, Valerio
T1  - Evaluation of porous silicon carbide monolithic honeycombs as volumetric receivers/collectors of concentrated solar radiation
JF  - Solar energy materials and solar cells
Y1  - 2007
SN  - 1879-3398 (E-Journal); 0927-0248 (Print)
VL  - Vol. 91
IS  - Iss. 6
SP  - 474
EP  - 488
ER  - 
TY  - RPRT
A1  - Hoffschmidt, Bernhard
A1  - Vaeßen, Christiane
A1  - Holzheid, Fabian
A1  - Gonsior, Daniel
T1  - Abschlussbericht Mix-SCR : Effizientes SCR-System unter Verwendung eines innovativen statischen Mischers : Kurztitel: Mix-SCR. Förderkennzeichen: 1782X05
Y1  - 2009
ER  - 
TY  - RPRT
A1  - Hoffschmidt, Bernhard
A1  - Reißel, Martin
A1  - Tamme, Rainer
A1  - Hack, Udo
A1  - Vostan, Peter
T1  - Entwicklung eines thermischen Sandspeichers im Temperaturbereich 400-900 Grad C (Sandspeicher) : Schlussbericht. Förderkennzeichen 1738X04
Y1  - 2008
ER  - 
TY  - CHAP
A1  - Fend, Thomas
A1  - Hoffschmidt, Bernhard
A1  - Reutter, Oliver
A1  - Sauerhering, Jörg
A1  - Pitz-Paal, Robert
T1  - Gas flow in hot porous materials: the solar air receiver and spin-off applications
T2  - Proceedings of the 4th Nanochannels, Microchannels and Minichannels - 2006 : presented at 4th Nanochannels, Microchannels and Minichannels, June 19 - 21, 2006, Limerick, Ireland
Y1  - 2006
SN  - 0-7918-4760-8
SP  - 507
EP  - 514
PB  - ASME
CY  - New York, NY
ER  - 
TY  - CHAP
A1  - Hoffschmidt, Bernhard
A1  - Schwarzer, Klemens
A1  - Späte, Frank
A1  - Kötter, Jens
A1  - Ebert, Miriam
A1  - Sierck, Olaf
T1  - Development of a small modular parabolic trough collector
T2  - 13th International Symposium Concentrated Solar Power and Chemical Energy Technologies : SolarPaces : June 20 - 23, 2006, Seville, Spain
Y1  - 2006
SN  - 8478345191
PB  - SolarPaces
CY  - [o.O.]
ER  - 
TY  - CHAP
A1  - Meliß, Michael
T1  - Biomasse-Potential
T2  - Energie aus Biomasse : Erfahrungen mit verschiedenen technischen Lösungen und Zukunftsaussichten; Tagungsbericht; [Fachtagung, 18. - 19. November 1985, Freising]
Y1  - 1985
SP  - 1
EP  - 30
PB  - Techn. Univ.
CY  - München
ER  - 
TY  - RPRT
A1  - Adler, J.
A1  - Heymer, H.
A1  - Richter, H. J.
A1  - Fend, Th.
A1  - Smirnova, O.
A1  - Rietbrock, P.
A1  - Petchenko, A.
A1  - Issendorff, F. v.
A1  - Steven, M.
A1  - Trimis, D.
A1  - Gonsior, Daniel
A1  - Helsper, Christoph
A1  - Hoffschmidt, Bernhard
T1  - INNOTRAP - innovative Rußfilter für LKW-Dieselmotoren : Abschlussbericht Förderkennzeichen 16IN0313
Y1  - 2009
ER  - 
TY  - CHAP
A1  - Beckmöller, S.
A1  - Wolters, J.
A1  - Breitbach, Gerd
A1  - Penkalla, H. J.
A1  - Schubert, F.
T1  - Microstructural dependent constitutive equation for inelastic analysis of internally cooled IN 738 LC turbine blades
T2  - Materials for advanced power engineering 1994 : proceedings of a conference held in Liege, Belgium, 3 - 6 Oct. 1994
Y1  - 1995
SN  - 0792330749
SP  - 829
EP  - 839
PB  - Kluwer
CY  - Dordrecht
ER  - 
TY  - RPRT
A1  - Breitbach, Gerd
T1  - Endbericht für das Projekt FilterCaps : Vorhabensbezeichnung: Entwicklung eines Wärmespeichers für strömungsrichtungsinvertierende Lüftungssysteme mit integrierter Filterwirkung : Förderkennzeichen: 1752X06
Y1  - 2009
ER  - 
TY  - CHAP
A1  - Meliß, Michael
T1  - Potential und technische Nutzbarkeit der regenerativen Energiequellen
T2  - 1. Deutsches Sonnenforum : Tagungsbericht ; [5. Tagung am 26. bis 28. September in Hamburg]. Bd. 2
Y1  - 1977
SP  - 473
EP  - 493
PB  - DGS
CY  - München
ER  - 
TY  - JOUR
A1  - Meliß, Michael
A1  - Windheim, R.
T1  - Energiequelle für morgen :  Möglichkeiten und Grenzen der Windenergienutzung - ein Statusbericht
JF  - VDI-Nachrichten. Bd. 31 (1977), H. 22
Y1  - 1977
SN  - 0042-1758
SP  - 37
EP  - 38
ER  - 
TY  - CHAP
A1  - Schumacher, Werner
A1  - Schwarzer, Klemens
A1  - Stukenbrock, Philipp
A1  - Rodriguez, Nadia
T1  - Entwicklung und Anwendungsgebiete solarthermischer Kraftwerke - Betriebsweise und Systemvarianten
T2  - Erneuerbare Energien. Bd. 2 : Ersatzbrennstoffe, Biomasse und Biogas, Solar- und Windenergie / Karl J. Thomé-Kozmiensky [Hrsg.]
Y1  - 2009
SN  - 978-3-935317-43-6
SP  - 401
EP  - 434
PB  - Thomé-Kozmiensky Verlag
CY  - Neuruppin
ER  - 
TY  - CHAP
A1  - Koll, Gerritt
A1  - Schwarzbözl, Peter
A1  - Hennecke, Klaus
A1  - Hoffschmidt, Bernhard
A1  - Hartz, Thomas
T1  - Solarthermisches Turmkraftwerk in Jülich
T2  - Erneuerbare Energien. Bd. 2 : Ersatzbrennstoffe, Biomasse und Biogas, Solar- und Windenergie / Karl J. Thomé-Kozmiensky [Hrsg.]
Y1  - 2009
SP  - 455
EP  - 460
PB  - Thomé-Kozmiensky Verlag
CY  - Neuruppin
ER  - 
TY  - JOUR
A1  - Meliß, Michael
T1  - Regenerative Energiequellen
JF  - Brennstoff, Wärme, Kraft : BWK ; das Energie-Fachmagazin. Bd. 37 (1985), H. 4
Y1  - 1985
SN  - 0006-9612 (Print) ; 1436-4883 (E-Journal)
SP  - 145
EP  - 150
ER  - 
TY  - JOUR
A1  - Meliß, Michael
T1  - Regenerative Energiequellen
JF  - Brennstoff, Wärme, Kraft : BWK ; das Energie-Fachmagazin. Bd. 36 (1984), H. 4
Y1  - 1984
SN  - 0006-9612 (Print) ; 1436-4883 (E-Journal)
SP  - 134
EP  - 139
ER  - 
TY  - JOUR
A1  - Meliß, Michael
T1  - Regenerative Energiequellen
JF  - Brennstoff, Wärme, Kraft : BWK ; das Energie-Fachmagazin. Bd. 35 (1983), H. 4
Y1  - 1983
SN  - 0006-9612 (Print) ; 1436-4883 (E-Journal)
SP  - 150
EP  - 155
ER  - 
TY  - JOUR
A1  - Meliß, Michael
T1  - Regenerative Energiequellen
JF  - Brennstoff, Wärme, Kraft : BWK ; das Energie-Fachmagazin. Bd. 34 (1982), H. 4
Y1  - 1982
SN  - 0006-9612 (Print) ; 1436-4883 (E-Journal)
SP  - 182
EP  - 189
ER  - 
TY  - JOUR
A1  - Meliß, Michael
T1  - Regenerative Energiequellen
JF  - Brennstoff, Wärme, Kraft : BWK ; das Energie-Fachmagazin. Bd. 33 (1981), H. 4
Y1  - 1981
SN  - 0006-9612 (Print) ; 1436-4883 (E-Journal)
SP  - 138
EP  - 145
ER  - 
TY  - JOUR
A1  - Stein, H.
A1  - Meliß, Michael
T1  - Die Bedeutung der Sonnenenergie für die zukünftige Energieversorgung der Bundesrepublik Deutschland
JF  - Din-Mitteilungen + Elektronorm. Bd. 59 (1980), H. 8
Y1  - 1980
SN  - 0722-2912
SP  - 434
EP  - 440
ER  - 
TY  - JOUR
A1  - Meliß, Michael
T1  - Regenerative Energiequellen
JF  - Brennstoff, Wärme, Kraft : BWK ; das Energie-Fachmagazin. Bd. 31 (1979), H. 4
Y1  - 1979
SN  - 0006-9612 (Print) ; 1436-4883 (E-Journal)
SP  - 147
EP  - 154
ER  - 
TY  - JOUR
A1  - Meliß, Michael
T1  - Regenerative Energiequellen
JF  - Brennstoff, Wärme, Kraft : BWK
Y1  - 1978
SN  - 0006-9612 (Print) ; 1436-4883 (E-Journal)
VL  - 30
IS  - 4
SP  - 151
EP  - 156
PB  - Springer-VDI-Verlag
CY  - Düsseldorf
ER  - 
TY  - JOUR
A1  - Meliß, Michael
A1  - Bünde, R.
T1  - Unkonventionelle Energiequellen - Entwicklungsstudien (4)
JF  - Brennstoff, Wärme, Kraft : BWK
Y1  - 1978
SN  - 0006-9612 (Print) ; 1436-4883 (E-Journal)
VL  - 30
IS  - 3
SP  - 120
EP  - 126
PB  - Springer-VDI-Verlag
CY  - Düsseldorf
ER  - 
TY  - CHAP
A1  - Meliß, Michael
T1  - Ergebnisse der deutschen Windenergiestudie
T2  - Energie vom Wind : 4. Tagung am 7. u. 8. Juni in Bremen : Bericht zur Tagung
Y1  - 1977
SP  - 47
EP  - 69
PB  - Dt. Gesellschaft für Sonnenenergie
CY  - München
ER  - 
TY  - CHAP
A1  - Fricke, Barbara
A1  - Hoffschmidt, Bernhard
T1  - Ecobalance of a solar thermal tower power plant with volumetric receiver
T2  - SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France
Y1  - 2010
SP  - 87
EP  - 88
PB  - Soc. OSC
CY  - Saint Maur
ER  - 
TY  - CHAP
A1  - Schwarzbözl, Peter
A1  - Pomp, Stefan
A1  - Koll, Gerrit
A1  - Hennecke, Klaus
A1  - Hartz, Thomas
A1  - Schmitz, Mark
A1  - Hoffschmidt, Bernhard
T1  - The solar tower Jülich - first operational experiences and test results
T2  - SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France
Y1  - 2010
SP  - 8
EP  - 9
PB  - Soc. OSC
CY  - Saint Maur
ER  - 
TY  - CHAP
A1  - Pomp, Stefan
A1  - Schwarzbözl, Peter
A1  - Koll, Gerrit
A1  - Hennecke, Klaus
A1  - Schmitz, Mark
A1  - Hoffschmidt, Bernhard
T1  - Advanced concept for a solar thermal power plant with open volumetric air receiver
T2  - SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France
Y1  - 2010
SP  - 97
EP  - 98
PB  - Soc. OSC
CY  - Saint Maur
ER  - 
TY  - JOUR
A1  - Reisgen, Uwe
A1  - Schleser, Markus
A1  - Abdurakhmanov, Aydemir
A1  - Turichin, Gleb
A1  - Valdaitseva, Elena
A1  - Bach, Friedrich-Wilhelm
A1  - Hassel, Thomas
A1  - Beniyashi, Alexander
T1  - Investigation of factors influencing the formation of weld defects in non-vacuum electron beam welding
JF  - The Paton welding journal
N2  - The influence of welding condition parameters and properties of material on formation of defects, such as humping and undercuts, in non-vacuum electron beam welding was investigated. The influence of separate welding parameters on the quality of welds was determined.
Y1  - 2012
SN  - 0957-798X
VL  - 2012
IS  - 2
SP  - 11
EP  - 18
PB  - Paton Publishing House
CY  - Kiev
ER  - 
TY  - CHAP
A1  - Achenbach, Timm
A1  - Bosch, Timo
A1  - Breitbach, Gerd
A1  - Sauerborn, Markus
T1  - Simulation zur Absorption und Wärmeübertragung an Solarturmabsorbern
T2  - 77. Jahrestagung der DPG und DPG-Frühjahrstagung : 4.-8.3.2013
Y1  - 2013
SP  - 1
EP  - 14
ER  - 
TY  - RPRT
A1  - Hoffschmidt, Bernhard
T1  - HelioScan : Machbarkeitsstudie zur Entwicklung einer radargestützten Positionsregelung von Heliostatenfeldern für Solarturmkraftwerke : Schlussbericht : Laufzeit: 01.07.2010 - 31.12.2012 : Förderkennzeichen 325234A
Y1  - 2013
PB  - Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Vieira da Silva, Maria Eugenia
A1  - Schwarzer, Klemens
A1  - Hoffschmidt, Bernhard
A1  - Pinheiro Rodrigues, Frederico
A1  - Schwarzer, Tarik
A1  - Costa Rocha, Paulo Alexandre
T1  - Mass transfer correlation for evaporation–condensation thermal process in the range of 70 °C–95 °C
JF  - Renewable energy
Y1  - 2013
SN  - 1879-0682 (E-Journal); 0960-1481 (Print)
VL  - Vol. 53
SP  - 174
EP  - 179
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Hoffschmidt, Bernhard
A1  - Alexopoulos, Spiros
T1  - Perspektiven für Solarthermische Kraftwerke im Sonnengürtel
T2  - Energiewende : Aspekte, Optionen, Herausforderungen : Vorträge auf der DPG-Frühjahrstagung Arbeitskreis Energie in der Deutschen Physikalischen Gesellschaft Berlin, 26. bis 28. März 2012 / hrsg. von Hardo Bruhns
Y1  - 2012
SP  - 81
EP  - 93
PB  - DPG
CY  - Baf Honnef
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  - https://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  - CHAP
A1  - Fricke, Barbara
A1  - Ziolko, C.
A1  - Anthrakidis, Anette
A1  - Alexopoulos, Spiros
A1  - Hoffschmidt, Bernhard
A1  - Giese, F.
A1  - Dillig, M.
T1  - InnoSol - environmental aspects of the open volumetric receiver technology
T2  - 30th ISES Biennial Solar World Congress 2011 : : Kassel, Germany, 28 August - 2 September 2011. Vol. 5
Y1  - 2012
SP  - 3895
EP  - 3900
PB  - Curran
CY  - Red Hook, NY
ER  - 
TY  - CHAP
A1  - Ziolko, Christoph
A1  - Fricke, Barbara
A1  - Anthrakidis, Anette
A1  - Hoffschmidt, Bernhard
A1  - Dillig, Marius
A1  - Giese, Frank
A1  - Schwarzbözl, Peter
T1  - Ökobilanzielle Aspekte technologischer Entwicklungen des Solarturmkraftwerks
T2  - Forschung und Entwicklung für solarthermische Kraftwerke : 14. Kölner Sonnenkolloquium Mittwoch, 13. Juli 2011, im Auditorium des Campus Jülich der FH Aachen : Kurzfassungen der Vorträge und Poster
Y1  - 2011
SP  - 2 S.
PB  - DLR
CY  - Köln
ER  - 
TY  - JOUR
A1  - Wolisz, Henryk
A1  - Schütz, Thomas
A1  - Blanke, Tobias
A1  - Hagenkamp, Markus
A1  - Kohrn, Markus
A1  - Wesseling, Mark
A1  - Müller, Dirk
T1  - Cost optimal sizing of smart buildings' energy system components considering changing end-consumer electricity markets
JF  - Energy
Y1  - 2017
U6  - https://doi.org/10.1016/j.energy.2017.06.025
VL  - 137
SP  - 715
EP  - 728
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Sauerborn, Markus
A1  - Klimek, J.
A1  - Hoffschmidt, Bernhard
A1  - Essen, H.
A1  - Sieger, S.
A1  - Biegel, G.
A1  - Göttsche, Joachim
A1  - Hilger, Patrick
T1  - Eurosun 2012 : radar technology for heliostat posititon control
T2  - Eurosun 2012 : Solar energy for a brighter future : conference proceedings : Rijeka, 18.-22.09.2012
Y1  - 2012
SP  - ID 80
CY  - Rijeka
ER  - 
TY  - CHAP
A1  - Göttsche, Joachim
A1  - Schwarzer, Klemens
A1  - Röther, Sascha
A1  - Jellinghaus, Sabine
A1  - Helten, G.
A1  - Wittmann, R.
T1  - Efficient daylighting, heating and shading with rooflight heliostats
T2  - Renewables in a changing climate : from Nano to Urban Scale : CISBAT 2009 : 2-3 September 2009, EPFL, Lausanne, Switzerland : proceedings
Y1  - 2009
SP  - 243
EP  - 246
PB  - Ecole Polytechnique Fédérale de Lausanne
CY  - Lausanne
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  - https://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  - CHAP
A1  - Duran Paredes, Ludwin
A1  - Mottaghy, Darius
A1  - Herrmann, Ulf
A1  - Groß, Rolf Fritz
T1  - Online ground temperature and soil moisture monitoring of a shallow geothermal system with non-conventional components
T2  - EGU General Assembly 2020
N2  - We present first results from a newly developed monitoring station for a closed loop geothermal heat pump test installation at our campus, consisting of helix coils and plate heat exchangers, as well as an ice-store system. There are more than 40 temperature sensors and several soil moisture content sensors distributed around the system, allowing a detailed monitoring under different operating conditions.In the view of the modern development of renewable energies along with the newly concepts known as Internet of Things and Industry 4.0 (high-tech strategy from the German government), we created a user-friendly web application, which will connect the things (sensors) with the open network (www). Besides other advantages, this allows a continuous remote monitoring of the data from the numerous sensors at an arbitrary sampling rate.Based on the recorded data, we will also present first results from numerical simulations, taking into account all relevant heat transport processes.The aim is to improve the understanding of these processes and their influence on the thermal behavior of shallow geothermal systems in the unsaturated zone. This will in turn facilitate the prediction of the performance of these systems and therefore yield an improvement in their dimensioning when designing a specific shallow geothermal installation.
Y1  - 2020
N1  - EGU General Assembly 2020, Online, 4–8 May 2020
ER  - 
TY  - CHAP
A1  - Kronhardt, Valentina
A1  - Alexopoulos, Spiros
A1  - Reißel, Martin
A1  - Latzke, Markus
A1  - Rendon, C.
A1  - Sattler, Johannes Christoph
A1  - Herrmann, Ulf
T1  - Simulation of operational management for the Solar Thermal Test and Demonstration Power Plant Jülich using optimized control strategies of the storage system
T2  - Energy procedia
Y1  - 2015
SN  - 1876-6102
SP  - 1
EP  - 6
ER  - 
TY  - JOUR
A1  - Göttsche, Joachim
A1  - Schwarzer, Klemens
A1  - Röther, S.
A1  - Jellinghaus, Sabine
T1  - Efficient daylighting, heating and shading with rooflight heliostats
JF  - Conference Internationale Energie Solaire et Batiment
Y1  - 2009
SP  - 243
EP  - 248
PB  - EPFL
CY  - Lausanne
ER  -