TY  - JOUR
A1  - Späte, Frank
A1  - Faber, Christian
A1  - Schwarzer, Klemens
A1  - Hartz, Thomas
T1  - Comparison of solar hot water systems in solar settlements - decentralized or centralized systems?
JF  - Proceedings / organised by: ISES Europe ... [Ed.: Deutsche Gesellschaft für Sonnenenergie e.V. - DGS, Munich ; PSE GmbH - Forschung Entwicklung Marketing, Freiburg]. - Vol. 1
Y1  - 2004
SN  - 3-9809656-1-9
N1  - EuroSun <5, 2004, Freiburg, Breisgau> ; Internationales Sonnenforum <14, 2004, Freiburg, Breisgau> ; Deutsche Gesellschaft für Sonnenenergie
SP  - 1-666-1-671
PB  - PSE
CY  - Freiburg [Breisgau]
ER  - 
TY  - CHAP
A1  - Spurmann, Jörn
A1  - Ohndorf, Andreas
A1  - Dachwald, Bernd
A1  - Seboldt, Wolfgang
A1  - Löb, Horst
A1  - Schartner, Karl-Heinz
T1  - Interplanetary trajectory optimization for a sep mission to Saturn
T2  - 60th International Astronautical Congress 2009
N2  - The recently proposed NASA and ESA missions to Saturn and Jupiter pose difficult tasks to mission designers because chemical propulsion scenarios are not capable of transferring heavy spacecraft into the outer solar system without the use of gravity assists. Thus our developed mission scenario based on the joint NASA/ESA Titan Saturn System Mission baselines solar electric propulsion to improve mission flexibility and transfer time. For the calculation of near-globally optimal low-thrust trajectories, we have used a method called Evolutionary Neurocontrol, which is implemented in the low-thrust trajectory optimization software InTrance. The studied solar electric propulsion scenario covers trajectory optimization of the interplanetary transfer including variations of the spacecraft's thrust level, the thrust unit's specific impulse and the solar power generator power level. Additionally developed software extensions enabled trajectory optimization with launcher-provided hyperbolic excess energy, a complex solar power generator model and a variable specific impulse ion engine model. For the investigated mission scenario, Evolutionary Neurocontrol yields good optimization results, which also hold valid for the more elaborate spacecraft models. Compared to Cassini/Huygens, the best found solutions have faster transfer times and a higher mission flexibility in general.
KW  - Spacecraft
KW  - Reusable Rocket Engines
KW  - Hybrid Propellants
Y1  - 2009
SN  - 9781615679089
N1  - 60th International Astronautical Congress 2009 (IAC 2009)
Held 12-16 October 2009, Daejeon, Republic of Korea.
SP  - 5234
EP  - 5248
ER  - 
TY  - PAT
A1  - Sponagel, Stefan
A1  - Wachowitz, Waldemar
T1  - Shaft seal : United States Patent 5,143,385 ; date of patent: Sep. 1, 1992 / assignee: Firma Carl Freudenberg
Y1  - 1992
N1  - Barcode: US005143385A ; Volltext über Datenbank: http://www.google.com/patents
PB  - [United States Patent and Trademark Office]
CY  - [Alexandria, VA]
ER  - 
TY  - JOUR
A1  - Sponagel, Stefan
A1  - Kilthau, G.
A1  - Spies, K. H.
T1  - Sealing mechanism of lip seals
JF  - Eleventh 11th International Conference on Fluid Sealing : proceedings of the 11th Internat. Conference on Fluid Sealing, held at Cannes, France 8 - 10 April, 1987 / organised and sponsored by BHRA, the Fluid Engineering Centre. Ed. B. S. Nau
Y1  - 1987
SN  - 3-540-51383-3
N1  - International Conference on Fluid Sealing <11, 1987, Cannes>
SP  - 748
EP  - 772
PB  - Elsevier
CY  - London
ER  - 
TY  - PAT
A1  - Sponagel, Stefan
A1  - Graf, Günter
A1  - Groß, Heinz
T1  - Method for manufacturing a sealing ring : United States Patent 4,861,536 ; date of patent: Aug. 12, 1989 / assignee: Firma Carl Freudenberg. Inventors: Gunter Graf ; Heinz Gross ; Stefan Sponagel
Y1  - 1989
N1  - Barcode: US004861536A ; Volltext über Datenbank: http://www.google.com/patents
PB  - [United States Patent and Trademark Office]
CY  - [Alexandria, VA]
ER  - 
TY  - PAT
A1  - Sponagel, Stefan
A1  - Graf, Günter
A1  - Groß, Heinz
T1  - Method for the manufacture of a sealing ring with a sealing lip having hydrodynamically acting return elements : United States Patent 4,850,097 ; date of patent: Jul. 25, 1989 / assignee: Firma Carl Freudenberg. Inventors: Gunter Graf ; Heinz Gross ; Stefan Sponagel
Y1  - 1989
N1  - Barcode: US004850097A ; Volltext über Datenbank: http://www.google.com/patents
PB  - [United States Patent and Trademark Office]
CY  - [Alexandria, VA]
ER  - 
TY  - JOUR
A1  - Sponagel, Stefan
A1  - Baroud, G.
A1  - Steffen, T.
A1  - Wu, J.
T1  - Parameter identification for cement infiltration of osteoporotic bone
JF  - Poromechanics II : Proceedings of the Second Biot Conference on Poromechanics Grenoble, France 26 - 28 August 2002 / ed. by J.-L. Auriault ...
Y1  - 2002
SN  - 90-5809-394-8
SP  - 55
EP  - 58
PB  - Balkema
CY  - Lisse [u.a.]
ER  - 
TY  - JOUR
A1  - Sponagel, Stefan
A1  - Baroud, G.
A1  - Falk, R.
A1  - Crookshank, M.
T1  - Experimental and theoretical investigation of directional permeability of human vertebral cancellous bone for cement infiltration. G. Baroud, R. Falk, M. Crookshank, S. Sponagel, T. Steffen
JF  - Journal of Biomechanics. 37 (2004), H. 2
Y1  - 2004
SN  - 0021-9290
SP  - 189
EP  - 196
ER  - 
TY  - JOUR
A1  - Sponagel, Stefan
A1  - Baroud, G.
A1  - Falk, R.
A1  - Crookshank, M.
T1  - Corrigendum to “Experimental and theoretical investigation of directional permeability of human vertebral cancellous bone for cement infiltration”. Baroud, G.; Falk, R.; Crookshank, M.; Sponagel, S.; Steffen, T.
JF  - Journal of Biomechanics. 37 (2004), H. 2
Y1  - 2004
SN  - 0021-9290
SP  - 1802
ER  - 
TY  - JOUR
A1  - Sponagel, Stefan
A1  - Akbay, U.
A1  - Becker, E.
A1  - Krozer, S.
T1  - Instability of slow viscometric flow
JF  - Mechanics Research Communications. 7 (1980), H. 4
Y1  - 1980
SN  - 0093-6413
SP  - 199
EP  - 204
ER  -