TY  - JOUR
A1  - Hammer, Thorben
A1  - Quitter, Julius
A1  - Mayntz, Joscha
A1  - Bauschat, J.-Michael
A1  - Dahmann, Peter
A1  - Götten, Falk
A1  - Hille, Sebastian
A1  - Stumpf, Eike
T1  - Free fall drag estimation of small-scale multirotor unmanned aircraft systems using computational fluid dynamics and wind tunnel experiments
JF  - CEAS Aeronautical Journal
N2  - New European Union (EU) regulations for UAS operations require an operational risk analysis, which includes an estimation of the potential danger of the UAS crashing. A key parameter for the potential ground risk is the kinetic impact energy of the UAS. The kinetic energy depends on the impact velocity of the UAS and, therefore, on the aerodynamic drag and the weight during free fall. Hence, estimating the impact energy of a UAS requires an accurate drag estimation of the UAS in that state. The paper at hand presents the aerodynamic drag estimation of small-scale multirotor UAS. Multirotor UAS of various sizes and configurations were analysed with a fully unsteady Reynolds-averaged Navier–Stokes approach. These simulations included different velocities and various fuselage pitch angles of the UAS. The results were compared against force measurements performed in a subsonic wind tunnel and provided good consistency. Furthermore, the influence of the UAS`s fuselage pitch angle as well as the influence of fixed and free spinning propellers on the aerodynamic drag was analysed. Free spinning propellers may increase the drag by up to 110%, depending on the fuselage pitch angle. Increasing the fuselage pitch angle of the UAS lowers the drag by 40% up to 85%, depending on the UAS. The data presented in this paper allow for increased accuracy of ground risk assessments.
KW  - Multirotor UAS
KW  - Drag estimation
KW  - CFD
KW  - Wind tunnel experiments
KW  - Wind milling
Y1  - 2023
U6  - https://doi.org/10.1007/s13272-023-00702-w
SN  - 1869-5590 (Online)
SN  - 1869-5582 (Print)
N1  - Corresponding author: Thorben Hammer
PB  - Springer
CY  - Wien
ER  - 
TY  - JOUR
A1  - Linden, A.
A1  - Fischöder, M.
A1  - Laack, Walter van
A1  - Staat, Manfred
T1  - Einschränkung von Taluskippung und -vorschub durch Sprunggelenkorthesen nach fibularer Bandruptur
JF  - OUP Zeitschrift für die orthopädische und unfallchirurgische Praxis
N2  - Die fibulare Bandruptur zählt zu einer der am häufigsten auftretenden Verletzungen des
Bewegungsapparats. In den meisten Fällen wird heute die konservativ frühfunktionelle Therapie mit Sprunggelenkorthesen allgemein bevorzugt. Im Rahmen der vorliegenden Studie wurden 14 verschiedene Sprunggelenkorthesen im Hinblick auf ihre Einschränkung von Taluskippung und Talusvorschub
untersucht. Zur Simulation einer fibularen Bandruptur wurde ein Unterschenkelmodell aus Holz mit Fußteil, mit angelegten Orthesen in einen Scheuba-Halteapparat eingespannt und mit 150 N seitlich sowie anterior-posterior belastet. Anhand der erstellten "gehaltenen" Röntgenaufnahmen konnten Taluskippung und Talusvorschub jeder einzelnen Orthese eindeutig bestimmt werden. Die meisten Orthesen erreichten zufriedenstellende Ergebnisse. Es stellte sich heraus, dass vor allem eine eng anliegende, im Gelenkbereich anatomisch angepasste Form vorteilhaft zu sein scheint.
N2  - The ankle sprain is actually one of the most common injuries. Nowadays the conservative pre-functional therapy with ankle braces is generally preferred. In the present study 14 different ankle braces were tested with regard to their ability to constrict the talar tilt and anterior drawer displacement. As part of the tests a wooden model of a foot was used in order to simulate an ankle sprain. This model was clamped in a Scheuba-device with different ankle braces and a force of 150 N was applied to it. The stress radiographs showed different talar tilts and anterior drawers of
each brace. Most ankle braces achieved a satisfying result. It has become obvious that a tight fitting and an anatomically designed shape seem to be favourable.
T2  - Constraint of talar tilt and anterior drawer by different ankle braces after the rupture of fibular ligaments
KW  - Sprunggelenkorthesen
KW  - fibulare Bandruptur
KW  - Distorsion des oberen Sprunggelenks
KW  - ankle sprain
KW  - rupture of the fibular ligament
KW  - ankle braces
Y1  - 2013
SN  - 2193-5785
U6  - https://doi.org/10.3238/oup.2013.0306-0309
VL  - 2
IS  - 6
SP  - 306
EP  - 309
PB  - Deutscher Ärzte-Verl.
CY  - Köln
ER  - 
TY  - CHAP
A1  - Alexopoulos, Spiros
A1  - Rau, Christoph
A1  - Sattler, Johannes Christoph
A1  - Kronhardt, Valentina
A1  - Hoffschmidt, Bernhard
T1  - Simulation von Solarturmkraftwerken mit offenem volumetrischen Receiver am Standort Italien
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  - 4 S.
PB  - DLR
CY  - Köln
ER  - 
TY  - CHAP
A1  - Alexopoulos, Spiros
A1  - Hoffschmidt, Bernhard
A1  - Rau, Christoph
A1  - Schmitz, M.
A1  - Schwarzbözl, P.
A1  - Pomp, Stefan
T1  - Simulation results for a hybridized operation of a gas turbine or a burner for a small solar tower power plant
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  - 82
EP  - 83
PB  - Soc. OSC
CY  - Saint Maur
ER  - 
TY  - CHAP
A1  - Ziolko, C.
A1  - Schmitz, M.
A1  - Sattler, Johannes Christoph
A1  - Khedim, Ahmed
A1  - Hoffschmidt, Bernhard
T1  - AlSol - the open volumetric receiver technology moves to Africa
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  - 93
EP  - 94
PB  - Soc. OSC
CY  - Saint Maur
ER  - 
TY  - CHAP
A1  - Alexopoulos, Spiros
A1  - Rau, Christoph
A1  - Hoffschmidt, Bernhard
A1  - Breitbach, Gerd
A1  - Latzke, Markus
T1  - Modelling and validation of a transient heat recovery steam generator of the solar tower power plant Juelich
T2  - Eurosun 2012 : Solar energy for a brighter future : conference proceedings : Rijeka, 18.-22.09.2012
Y1  - 2012
SP  - ID 97
CY  - Rijeka
ER  - 
TY  - CHAP
A1  - Anthrakidis, Anette
T1  - Prüfeinrichtung zur Bestimmung der Leistungsfähigkeit von solarthermischen Kollektoren bis 200 Grad C
T2  - 22. Symposium Thermische Solarenergie : 09. bis 11. Mai 2012, Kloster Banz, Bad Staffelstein
Y1  - 2012
SN  - 978-3-941785-89-2
SP  - 134
EP  - 135
PB  - OTTI
CY  - Regensburg
ER  - 
TY  - CHAP
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Zander, W.
A1  - Schubert, J.
A1  - Sukoyan, L. H.
A1  - Begoyan, V.
A1  - Buniatyan, V. V.
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Chemische Sensoren mit Bariumstrontiumtitanat als funktionelle Schicht zur Multiparameterdetektion
T2  - 11. Dresdner Sensor-Symposium : 9.-11.12.2013
Y1  - 2013
SN  - 978-3-9813484-5-3
SP  - 368
EP  - 372
ER  - 
TY  - CHAP
A1  - Schusser, Sebastian
A1  - Bäcker, Matthias
A1  - Leinhos, Marcel
A1  - Krischer, M.
A1  - Wenzel, L.
A1  - Poghossian, Arshak
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Sensorkonzept zur in vitro Echtzeitmessung des Degradationsverhaltens von biodegradierbaren Biopolymeren
T2  - 11. Dresdner Sensor-Symposium : 9.-11.12.2013
Y1  - 2013
SN  - 978-3-9813484-5-3
SP  - 174
EP  - 177
ER  - 
TY  - CHAP
A1  - Bung, Daniel Bernhard
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  -