@misc{RichterZanounEgbers, author = {Richter, Stefan and Zanoun, El-Sayed and Egbers, Christoph}, title = {Investigation of Large Scale Motion Interaction with the Near-Wall Turbulence}, series = {Proceedings in applied mathematics and mechanics : PAMM}, volume = {20}, journal = {Proceedings in applied mathematics and mechanics : PAMM}, number = {1}, issn = {1617-7061}, doi = {10.1002/pamm.202000331}, pages = {2}, language = {en} } @misc{EgbersGellertHarlanderetal., author = {Egbers, Christoph and Gellert, Marcus and Harlander, Uwe and Wang, Yongtai and R{\"u}diger, G{\"u}nther}, title = {Investigation of Stratorotational Instability (SRI) in Taylor-Couette flows with axial temperature gradient}, language = {en} } @inproceedings{MeierJongmannsEgbers, author = {Meier, Martin and Jongmanns, Marcel and Egbers, Christoph}, title = {Investigations on thermal electro-hydrodynamic convection in a cylindrical gap}, series = {Experimentelle Str{\"o}mungsmechanik, 24. Fachtagung 6.-8. September 2016 Cottbus}, booktitle = {Experimentelle Str{\"o}mungsmechanik, 24. Fachtagung 6.-8. September 2016 Cottbus}, editor = {Egbers, Christoph}, publisher = {German Association for Laser Anemometry GALA e.V.}, address = {Karlsruhe}, isbn = {978-3-9816764-2-6}, pages = {S. 39}, language = {en} } @inproceedings{SeeligHarlanderFaulwetteretal., author = {Seelig, Torsten and Harlander, Uwe and Faulwetter, Robin and Egbers, Christoph}, title = {Irregular and singular vector growth in the differentially heated rotating annulus}, language = {en} } @inproceedings{SeeligHarlanderFaulwetteretal., author = {Seelig, Torsten and Harlander, Uwe and Faulwetter, Robin and Egbers, Christoph}, title = {Irregular and singular vector growth in the differentially heated rotating annulus}, language = {en} } @misc{SeeligHarlanderFaulwetteretal., author = {Seelig, Torsten and Harlander, Uwe and Faulwetter, Robin and Egbers, Christoph}, title = {Irregularity and singular vector growth of the differentially heated rotating annulus flow}, language = {en} } @misc{RoddaHarlanderVincze, author = {Rodda, Costanza and Harlander, Uwe and Vincze, Miklos}, title = {Jet stream variability in a polar warming scenario - a laboratory perspective}, series = {Weather and Climate Dynamics}, volume = {3}, journal = {Weather and Climate Dynamics}, number = {3}, issn = {2698-4016}, doi = {10.5194/wcd-3-937-2022}, pages = {937 -- 950}, language = {en} } @techreport{UhligKirnerPreussetal., author = {Uhlig, Benedict and Kirner, Claus and Preuß, Ann-Christin and Graf, Johann and Neben, Matthias and Zaussinger, Florian}, title = {Kolbenring-{\"O}ltransport II : {\"O}ltransport durch die Kolbenringe}, publisher = {FVV, Forschungsvereinigung Verbrennungskraftmaschinen}, address = {Frankfurt am Main}, pages = {70}, abstract = {Ziele des Vorhabens sind die Verbesserung der Messtechnik f{\"u}r tribologische Untersuchungen in der Kolbengruppe aus dem Vorl{\"a}ufervorhaben Kolbenring-{\"O}ltransport I und die Untersuchung von verschiedenen Betriebsbedingungen und Komponenten hinsichtlich ihres Einflusses auf den {\"O}lhaushalt. Der Fokus liegt auf der verbesserten Aufl{\"o}sung der Schmierfilmdickenmessung und der Ringstoßlagen. Mit der erweiterten Kapillar- und Lichtleiterkonfiguration werden neue {\"O}ltransportvorg{\"a}nge entlang des Kolbenringpakets mittels Tracerinjektion und simultaner LiF-Messung beobachtet. Das methodische Vorgehen bei der optischen Analyse des Kapillarf{\"u}llungsgrades wird an einem Labor-Druckpr{\"u}fstand weiterentwickelt. Des Weiteren werden komplexe Simulationsmodelle erstellt, mit denen die Kolbensekund{\"a}r-bewegung, die Kolbenringbewegung, die Gasstr{\"o}mung im Ringpaket und der {\"O}ltransport im Ringpaket gekl{\"a}rt werden k{\"o}nnen. Die Kolbensekund{\"a}rbewegungsrechnung basiert auf einer FEM-Diskretisierung die aus CAD-Modellen s{\"a}mtlicher Bauteile abgeleitet ist. Die dreidimensionale Berechnung der Kolbenringbewegung erfolgt unter Ber{\"u}cksichtigung dynamisch wirkender Kr{\"a}fte aus der Bewegung, der Ringreibung, dem Gasdruck und den Zwischenring- dr{\"u}cken. Die Elastizit{\"a}t der Ringe wird ber{\"u}cksichtigt, so dass Biegung, Torsion und damit auch das Twisten abgebildet werden k{\"o}nnen. Nut- und Ringgeometrie sowie thermisch bedingte Verz{\"u}ge fließen ebenfalls in die Berechnung mit ein. Als Ergebnisgr{\"o}ßen stehen neben den Ringbewegungen und -lagen auch die Gasstr{\"o}mungen und -dr{\"u}cke, Schmierfilmh{\"o}hen und Verlustleistungen zur Verf{\"u}gung.}, language = {de} } @inproceedings{KochHarlanderHollerbachetal., author = {Koch, Sandy and Harlander, Uwe and Hollerbach, Rainer and Egbers, Christoph}, title = {Laboratory experiment and numerical simulations of inertial wave interactions in a rotating spherical shell}, language = {en} } @misc{KochHarlanderHollerbachetal., author = {Koch, Sandy and Harlander, Uwe and Hollerbach, Rainer and Egbers, Christoph}, title = {Laboratory experiment of inertial wave-interactions in a rotating spherical shell}, language = {en} } @misc{KochHarlanderHollerbachetal., author = {Koch, Sandy and Harlander, Uwe and Hollerbach, Rainer and Egbers, Christoph}, title = {Laboratory experiments and numerical simulations of inertial wave-interactions in a rotating spherical shell}, language = {en} } @phdthesis{Dahley, author = {Dahley, Sandy}, title = {Laboratory experiments and numerical simulations of inertial waves in a rotating spherical shell}, publisher = {Cuvillier Verlag}, address = {G{\"o}ttingen}, isbn = {978-3-73699-198-9}, language = {en} } @misc{KochHarlanderHollerbachetal., author = {Koch, Sandy and Harlander, Uwe and Hollerbach, Rainer and Egbers, Christoph}, title = {Laboratory experiments of inertial waves in containers rotating with time modulation}, language = {en} } @inproceedings{ShahirpourSesterhennEgbers, author = {Shahirpour, Amir and Sesterhenn, J{\"o}rn and Egbers, Christoph}, title = {Lagrangian Dynamic Mode Decomposition to capture Linearized Coherent Structures}, series = {Fachtagung der Gesellschaft f{\"u}r Angewandte Mathematik und Mechanik (GAMM), Braunschweig, 7.-11. M{\"a}rz 2016}, booktitle = {Fachtagung der Gesellschaft f{\"u}r Angewandte Mathematik und Mechanik (GAMM), Braunschweig, 7.-11. M{\"a}rz 2016}, pages = {16}, language = {en} } @misc{DurstZanoun, author = {Durst, Franz and Zanoun, El-Sayed}, title = {Laminar pipe flow instability : a theoretical-experimental perspective}, series = {Fluids}, volume = {10}, journal = {Fluids}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {2311-5521}, doi = {10.3390/fluids10080216}, pages = {1 -- 21}, abstract = {This paper revisits the theoretically predicted inherent stability of fully developed laminar pipe flow, which remains unconfirmed by experimental evidence. A recently developed theory of pipe-flow stability/instability addresses the gap between experimental observations and classical theoretical predictions by accounting for a parallel secondary flow through the pipe's roughness layer that accompanies the main stream. This secondary flow alters the near-wall velocity profile in the rough-wall region, creating an inflection point that promotes shear-driven instabilities and triggers the laminar-to-turbulent transition. A stability factor 𝑆=𝐷𝑐/𝐷 is introduced, where D is the nominal pipe diameter and 𝐷𝑐 refers to the critical pipe diameter. The pipe flow remains laminar and stable for 𝑆>1.0, and becomes unstable for 𝑆<1. Various experimental findings are theoretically derived, and the laminar-to-turbulent transition is identified at 𝑆=1.0. Particular attention is paid to the dependence of flow transition on both pipe diameter and pipe length. Rather than relying on a critical Reynolds number 𝑅𝑒𝑐, this study proposes the critical pipe diameter 𝐷𝑐 as the key parameter governing the laminar pipe flow instability, where 𝑅𝑒𝑐 refers here to the condition-dependent threshold at which laminar pipe flow becomes unstable and transition to turbulence occurs. The present analysis further suggests that instability arises only if the pipe length L exceeds a critical threshold 𝐿𝑐, that is, 𝐿>𝐿𝑐. The theoretical treatment presented provides deeper physical insights into the onset of laminar pipe flow instability including the phenomenon of reverse transition. It also distinguishes between natural and forced flow transitions, providing a refined understanding of the transition process. Finally, suggestions for future experimental work are made to further validate or challenge this new theoretical perspective on pipe flow instability.}, language = {en} } @inproceedings{FroitzheimMerboldEgbersetal., author = {Froitzheim, Andreas and Merbold, Sebastian and Egbers, Christoph and Ezeta, Rodrigo and Lohse, D. and Sun, C.}, title = {Large scale vortices in the Taylor-Couette flow}, series = {The 12th European Fluid Mechanics Conference, 9 September 2018 - 13 September 2018, Vienna, Austria}, booktitle = {The 12th European Fluid Mechanics Conference, 9 September 2018 - 13 September 2018, Vienna, Austria}, pages = {1}, language = {en} } @misc{BuchwaldHasanuzzamanMerboldetal., author = {Buchwald, Tom and Hasanuzzaman, Gazi and Merbold, Sebastian and Schanz, Daniel and Egbers, Christoph and Schr{\"o}der, Andreas}, title = {Large-scale flow field and aerosol particle transport investigations in a classroom using 2D-Shake-The-Box Lagrangian Particle Tracking}, series = {Heliyon}, volume = {9}, journal = {Heliyon}, number = {12}, issn = {2405-8440}, doi = {10.1016/j.heliyon.2023.e22826}, language = {en} } @incollection{KitoZanounJehringetal., author = {Kito, Mizuki and Zanoun, El-Sayed and Jehring, Lothar and Egbers, Christoph}, title = {Laser-Doppler Anemometry in Turbulent Boundary Layers Induced by Different Tripping Devices Compared with Recent Theories}, language = {en} } @inproceedings{StueckeNobisSchmidtetal., author = {St{\"u}cke, Peter and Nobis, Matthias and Schmidt, M. and Scurtu, Nicoleta and Egbers, Christoph}, title = {Laseroptische und numerische Untersuchung von Taylorwirbeln}, language = {de} } @inproceedings{YousryMerboldEgbers, author = {Yousry, Mohamed and Merbold, Sebastian and Egbers, Christoph}, title = {LDA measurements over hexagonal structured cavity inside turbulent channel flow}, series = {Experimentelle Str{\"o}mungsmechanik, 25. Fachtagung, 5.-7. September 2017, Karlsruhe}, booktitle = {Experimentelle Str{\"o}mungsmechanik, 25. Fachtagung, 5.-7. September 2017, Karlsruhe}, editor = {Ruck, Bodo}, publisher = {Deutsche Gesellschaft f{\"u}r Laser-Anemometrie GALA e.V.}, address = {Karlsruhe}, isbn = {978-3-9816764-3-3}, pages = {S. 22}, language = {en} } @incollection{StueckeLehmannScurtuetal., author = {St{\"u}cke, Peter and Lehmann, B. and Scurtu, Nicoleta and Egbers, Christoph}, title = {LDA-Messung in Zylinderspaltstr{\"o}mungen bei engen Spaltweiten}, language = {de} } @incollection{LarcherBeyerEgbers, author = {Larcher, Thomas von and Beyer, Wolfgang and Egbers, Christoph}, title = {LDA-Messungen zur Untersuchung barokliner Instabilit{\"a}ten}, language = {de} } @inproceedings{LarcherEgbers, author = {Larcher, Thomas von and Egbers, Christoph}, title = {LDA-Messungen zur Untersuchung barokliner Instabilit{\"a}ten, Lasermethoden in der Str{\"o}mungsmesstechnik}, language = {de} } @inproceedings{SitteLarcherEgbers, author = {Sitte, B. and Larcher, Thomas von and Egbers, Christoph}, title = {LDV-measurements on higher order dynamicsof baroclinic waves}, language = {en} } @misc{TravnikovEgbers, author = {Travnikov, Vadim and Egbers, Christoph}, title = {Linear stability analysis of the convective flow in a spherical gap with rotating inner surface}, series = {International Journal of Heat and Mass Transfer}, volume = {148}, journal = {International Journal of Heat and Mass Transfer}, issn = {0017-9310}, doi = {10.1016/j.ijheatmasstransfer.2019.119052}, pages = {10}, language = {en} } @misc{LabarbeLeGalHarlanderetal., author = {Labarbe, Joris and Le Gal, Patrice and Harlander, Uwe and Le Diz{\`e}s, St{\´e}phane and Favier, Benjamin}, title = {Localized layers of turbulence in stratified horizontally sheared Poiseuille flow}, series = {Fluid Dynamics}, journal = {Fluid Dynamics}, pages = {20}, language = {en} } @misc{FruehSzaboEgbersetal., author = {Fr{\"u}h, Wolf-Gerrit and Szabo, Peter and Egbers, Christoph and Harlander, Uwe}, title = {Locating sources of variability in the transition to Structural Vacillation in the baroclinic annulus}, series = {EGU General Assembly 2020, Online | 4-8 May 2020}, journal = {EGU General Assembly 2020, Online | 4-8 May 2020}, doi = {10.5194/egusphere-egu2020-7262}, language = {en} } @misc{HarlanderRidderinkhofSchoutenetal., author = {Harlander, Uwe and Ridderinkhof, H. and Schouten, M. W. and Ruijter, W. P. M. de}, title = {Long term observations of transport eddies, and Rossby waves in the Mozambique Channel}, doi = {10.1029/2008JC004846}, language = {en} } @inproceedings{ScurtuGorenzEgbers, author = {Scurtu, Nicoleta and Gorenz, Paul and Egbers, Christoph}, title = {Magnetorotational-type instability in Couette-Taylor flows of viscoelastic polymeric liquids}, language = {en} } @misc{BorciaBestehornBorciaetal., author = {Borcia, I. D. and Bestehorn, M. and Borcia, R. and Sch{\"o}n, F.-T. and Harlander, U. and Richter, S.}, title = {Mean flow generated by asymmetric periodic excitation in an annular channel}, series = {The European Physical Journal Special Topics}, volume = {233 (2024)}, journal = {The European Physical Journal Special Topics}, publisher = {Springer}, doi = {10.1140/epjs/s11734-024-01181-8}, pages = {1665 -- 1672}, language = {en} } @inproceedings{KleinGhasemiSeeligetal., author = {Klein, Marten and Ghasemi, Abouzar and Seelig, Torsten and Borcia, Ion-Dan and Harlander, Uwe and Will, Andreas}, title = {Mean flow generation and inertial wave attractors in a librating annulus: DNS and theory}, series = {European Geosciences Union, General Assembly 2015, Vienna, Austria, 13 April - 17 May 2015}, booktitle = {European Geosciences Union, General Assembly 2015, Vienna, Austria, 13 April - 17 May 2015}, publisher = {European Geophysical Society}, address = {Katlenburg-Lindau}, language = {en} } @misc{GhasemiKleinWilletal., author = {Ghasemi, Abouzar and Klein, Marten and Will, Andreas and Harlander, Uwe}, title = {Mean flow generation by an intermittently unstable boundary layer over a sloping wall}, series = {Journal of Fluid Mechanics}, journal = {Journal of Fluid Mechanics}, number = {vol. 853}, issn = {1750-6859}, doi = {10.1017/jfm.2018.552}, pages = {111 -- 149}, language = {en} } @misc{GhasemiKleinHarlanderetal., author = {Ghasemi, Abouzar and Klein, Marten and Harlander, Uwe and Kurgansky, Michael V. and Schaller, Eberhard and Will, Andreas}, title = {Mean flow generation by G{\"o}rtler vortices in a rotating annulus with librating side walls}, series = {Physics of Fluids}, volume = {28}, journal = {Physics of Fluids}, number = {056603}, doi = {10.1063/1.4948406}, pages = {1 -- 23}, abstract = {Time periodic variation of the rotation rate of an annulus induces in supercritical regime an unstable Stokes boundary layer over the cylinder side walls, generating G{\"o}rtler vortices in a portion of a libration cycle as a discrete event. Numerical results show that these vortices propagate into the fluid bulk and generate an azimuthal mean flow. Direct numerical simulations of the fluid flow in an annular container with librating outer (inner) cylinder side wall and Reynolds-averaged Navier-Stokes (RANS) equations as diagnostic equations are used to investigate generation mechanism of the retrograde (prograde) azimuthal mean flow in the bulk. First, we explain, phenomenologically, how absolute angular momentum of the bulk flow is mixed and changed due to the propagation of the G{\"o}rtler vortices, causing a new vortex of basin size. Then we investigate the RANS equations for intermediate time scale of the development of the G{\"o}rtler vortices and for long time scale of the order of several libration periods. The former exhibits sign selection of the azimuthal mean flow. Investigating the latter, we predict that the azimuthal mean flow is proportional to the libration amplitude squared and to the inverse square root of the Ekman number and libration frequency and then confirms this using the numerical data. Additionally, presence of an upscale cascade of energy is shown, using the kinetic energy budget of fluctuating flow.}, language = {en} } @inproceedings{SeeligGhasemiKurganskyetal., author = {Seelig, Torsten and Ghasemi, Abouzar and Kurgansky, Michael V. and Klein, Marten and Will, Andreas and Harlander, Uwe}, title = {Mean flow generation due to longitudinal librations of sidewalls of a rotating annulus}, series = {15th European turbulence conference (ETC), Delft, The Netherlands (2015)}, booktitle = {15th European turbulence conference (ETC), Delft, The Netherlands (2015)}, language = {en} } @misc{KurganskySeeligKleinetal., author = {Kurgansky, Michael V. and Seelig, Torsten and Klein, Marten and Will, Andreas and Harlander, Uwe}, title = {Mean flow generation due to longitudinal librations of sidewalls of a rotating annulus}, series = {Geophysical \& Astrophysical Fluid Dynamics}, volume = {114}, journal = {Geophysical \& Astrophysical Fluid Dynamics}, number = {6}, issn = {1029-0419}, doi = {10.1080/03091929.2019.1692829}, pages = {762}, abstract = {Laboratory experiments with a rotating cylindrical annulus arereported that reveal a prograde jet, which is adjacent to a (longitu-dinally) librating inner straight cylindrical wall. Here, wall libration isrealised as a time-harmonic modulation of the inner cylinder's rota-tion rate. The outer cylindrical wall and bottom and top lids rotatewith constant angular velocity. The main purpose of our study is tocontribute to a qualitative and quantitative understanding of non-linearities that are present in oscillating, but centrifugally stable,vertical boundary layers frequently encountered in rotating wall-bounded flows. We consider a problem that is in a sense comple-mentary to that of previous works that focused on oscillating Ekmanlayers but neglected the vertical Stokes-Stewartson layers. A sim-ple analytical model is proposed that is able to predict the magni-tude and spatial structure of the emerging prograde near-wall jet interms of nonlinearity inherent in the inner cylinder's boundary layerdynamics.}, language = {en} } @misc{XuHarlander, author = {Xu, Wenchao and Harlander, Uwe}, title = {Mean flow generation in rotating annulus with stochastic methods}, series = {17th European Turbulence Conference, ETC 2019, September 3 - 6, 2019, Torino, Italy}, journal = {17th European Turbulence Conference, ETC 2019, September 3 - 6, 2019, Torino, Italy}, address = {Turin}, pages = {1}, language = {en} } @incollection{ZanounDurstEgbers, author = {Zanoun, El-Sayed and Durst, F. and Egbers, Christoph}, title = {Mean Flow Properties in Smooth Pipe Flow Experiment}, language = {en} } @misc{SchoenHarlanderBorciaetal., author = {Sch{\"o}n, Franz-Theo and Harlander, Uwe and Borcia, Ion Dan and Borcia, Rodica and Bestehorn, Michael}, title = {Mean fluid transport in an oscillating circular channel with asymmetric forcing}, series = {Water waves : an interdisciplinary journal}, volume = {2025}, journal = {Water waves : an interdisciplinary journal}, publisher = {Birkh{\"a}user, part of Springer Nature}, address = {Basel}, issn = {2523-3688}, doi = {10.1007/s42286-025-00121-w}, pages = {1 -- 21}, abstract = {We investigate surface waves in an oscillating circular channel with local topography. The focus is on spatially or temporally breaking this dynamic system's symmetry. Asymmetrical wave dynamics and a mean flux excitation are detected to varying degrees, depending on the two input parameters, fluid depth and the tank's oscillation frequency. The fluid resonates around multiples of the fundamental eigenfrequency of the channel. The development of solitary wave-trains (undular bores) is observed in these resonance bands. A particle image velocimetry system measures the velocity field in the vertical plane of the free surface flow. Moreover, we are using 17 evenly distributed ultrasonic sensors to measure the surface displacement. This makes it possible to find out how strongly the mean flux depends on the resonance frequencies and to study the influence of the surface waves on the symmetry breaking. A numerical long-wave model helps to isolate the various factors influencing the mean flux.}, language = {en} } @misc{UhligPreussGrafetal., author = {Uhlig, Benedict and Preuß, Ann-Christin and Graf, Johann and Neben, Matthias}, title = {Measurement and Simulation of the Oil Supply at the Piston Assembly}, series = {MTZ worldwide}, volume = {78}, journal = {MTZ worldwide}, number = {2}, issn = {2192-9114}, doi = {10.1007/s38313-016-0167-2}, pages = {72 -- 77}, abstract = {The main focus of the project series "Piston Ring Oil Transport" is the investigation of the tribological conditions in the piston assembly. Within the first part of the project, a 0.5-l single-cylinder research engine was built up [1, 2], which is equipped with numerous sensors to measure the tribological circumstances. In the second project part [3] presented here, additional simulation models are developed, which gain accuracy compared to the recorded measurement data and contribute significantly to an understanding of the oil supply at the piston assembly.}, language = {en} } @misc{FechtWunderlichMeieretal., author = {Fecht, Hans-J{\"o}rg and Wunderlich, Rainer and Meier, Martin and Sprenger, Heinz}, title = {Measurement of Thermophysical Properties of Metallic Melts for High Quality Castings}, language = {en} } @inproceedings{BabcsanLeitlmeierMeieretal., author = {Babcsan, N. and Leitlmeier, D. and Meier, M. and Banhart, J. and Garcia-Moreno, F.}, title = {Measurements on cell walls and Plateau borders of particle stabilized foams}, series = {A collection of papers presented at the 5th European Conference on Foams, Emulsions, and Applications, EUFOAM 2004}, booktitle = {A collection of papers presented at the 5th European Conference on Foams, Emulsions, and Applications, EUFOAM 2004}, editor = {Vignes-Adler, Mich{\`e}le}, publisher = {Elsevier}, address = {Amsterdam [u.a.]}, language = {en} } @misc{ButtJehringEgbers, author = {Butt, Usman and Jehring, Lothar and Egbers, Christoph}, title = {Mechanism of drag reduction for circular cylinders with patterned surface}, series = {International journal of heat and fluid flow}, volume = {Vol. 45}, journal = {International journal of heat and fluid flow}, issn = {1879-2278}, pages = {128 -- 134}, language = {en} } @misc{UhligPreussGrafetal., author = {Uhlig, Benedict and Preuß, Ann-Christin and Graf, Johann and Neben, Matthias}, title = {Messtechnische und simulative Untersuchung des {\"O}lhaushalts an der Kolbengruppe}, series = {MTZ - Motortechnische Zeitschrift}, volume = {78}, journal = {MTZ - Motortechnische Zeitschrift}, number = {2}, issn = {2192-8843}, doi = {10.1007/s35146-016-0175-4}, pages = {76 -- 81}, abstract = {Die Projektreihe Kolbenring-{\"O}ltransport dient der Untersuchung der tribologischen Zust{\"a}nde in der Kolbengruppe. Dabei wurde im ersten Projektabschnitt ein 0,5-l-Einzylinder-Forschungsmotor aufgebaut, der mit zahlreichen Sensoren ausger{\"u}stet ist, um diese Zust{\"a}nde messtechnisch zu erfassen. Im zweiten, hier ausschnittsweise vorgestellten Projektabschnitt wurden zus{\"a}tzliche Simulationsmodelle implementiert, die durch Abgleich mit den aufgezeichneten Messdaten an Genauigkeit gewinnen und zum Verst{\"a}ndnis des {\"O}lhaushalts in der Kolbengruppe erheblich beitragen.}, language = {de} } @misc{MeierMeyerMutabazietal., author = {Meier, Martin and Meyer, Antoine and Mutabazi, Innocent and Egbers, Christoph}, title = {Microgravity experiments on thermo-electric flows}, series = {26th European Low Gravity Research Association Biennial Symposium and General Assembly, Granada (Spanien), September 24-27, 2019}, journal = {26th European Low Gravity Research Association Biennial Symposium and General Assembly, Granada (Spanien), September 24-27, 2019}, pages = {293 -- 294}, language = {en} } @article{FuttererGellertHuschtoetal., author = {Futterer, Birgit and Gellert, Marcus and Huschto, Michael and Larcher, Thomas von and Egbers, Christoph}, title = {Microgravity Science on International Space Station (ISS): The Geoflow Experiment}, language = {en} } @inproceedings{Futterer, author = {Futterer, Birgit}, title = {Minimierung von Diskretisierungsfehlern bei gitterunabh{\"a}ngiger Elektrodenpositionierung}, series = {62. Jahrestagung der Deutschen Geophysikalischen Gesellschaft im Jahr der Geowissenschaften}, booktitle = {62. Jahrestagung der Deutschen Geophysikalischen Gesellschaft im Jahr der Geowissenschaften}, publisher = {Deutsche Geophysikalische Gesellschaft}, address = {Hannover}, language = {de} } @misc{KupkaZaussingerMontgomery, author = {Kupka, Friedrich and Zaussinger, Florian and Montgomery, M. H.}, title = {Mixing and overshooting in surface convection zones of DA white dwarfs: First results from ANTARES}, series = {Monthly Notices of the Royal Astronomical Society}, volume = {474}, journal = {Monthly Notices of the Royal Astronomical Society}, number = {4}, issn = {1365-2966}, pages = {4660 -- 4671}, language = {en} } @phdthesis{Haun, author = {Haun, Peter}, title = {Modelling of thermo-electro hydrodynamic (TEHD) convection}, edition = {1st edition}, publisher = {Cuvillier Verlag}, address = {G{\"o}ttingen}, isbn = {978-3-689-52666-5}, doi = {10.61061/ISBN_9783689526665}, pages = {XXIV, 369}, abstract = {In Thermo-Electro Hydrodynamics (TEHD), an electric field is applied to a fluid within a heated domain to induce thermal convection. The fluid and the electric field must meet specific conditions to establish a dielectrophoretic force that acts as a buoyancy force on the fluid. This buoyancy force is utilised in experiments to replicate gravitational buoyancy, explore resulting flow structures, or develop heat transfer systems without moving parts. In this study, the electric force field acting on a dielectric fluid in a capacitor is derived from the Maxwell equations and coupled with the Navier-Stokes equation for fluid motion. Furthermore, an Open Source Field Operation and Manipulation (OpenFOAM) solver is extended to incorporate TEHD momentum and energy-contributing terms. In a dimensional analysis, dimensionless parameters are derived and tested. Therefore, parameter studies in 2D approximations of planar and cylindrical geometries are done. Additionally, the 2D investigations are utilised to study the behaviour of heat transfer and boundary layer properties, and some scaling laws are derived. Finally, 3D spherical shell microgravity experiments are analysed and linked to the results of 3D numerical analysis. The results verify the derived methods, which are expanded and applied to the upcoming space experiment, AtmoFlow.}, language = {en} } @misc{GaillardSzaboTravnikovetal., author = {Gaillard, Yann and Szabo, Peter and Travnikov, Vadim and Egbers, Christoph}, title = {Modelling Thermo-Electrohydrodynamic Convection in Rotating Spherical Shell Using OpenFOAM ®}, series = {OpenFOAM® Journal}, volume = {5 (2025)}, journal = {OpenFOAM® Journal}, doi = {10.51560/ofj.v5.136}, pages = {1 -- 16}, language = {en} } @incollection{ZanounEgbersJehring, author = {Zanoun, El-Sayed and Egbers, Christoph and Jehring, Lothar}, title = {Modified Optical and Thermal Anemometers for Laminar and Turbulent Boundary Layers Investigation}, language = {en} }