@misc{MerboldHamedeFroitzheimetal., author = {Merbold, Sebastian and Hamede, Mohammed Hussein and Froitzheim, Andreas and Egbers, Christoph}, title = {Flow regimes in a very wide-gap Taylo-Couette flow with counter rotating cylinders}, series = {Philosophical transactions of the Royal Society : Series A, Mathematical, physical and engineering sciences}, volume = {381}, journal = {Philosophical transactions of the Royal Society : Series A, Mathematical, physical and engineering sciences}, number = {2246}, issn = {1364-503X}, doi = {10.1098/rsta.2022.0113}, language = {en} } @misc{HamedeMerboldEgbers, author = {Hamede, Mohammed Hussein and Merbold, Sebastian and Egbers, Christoph}, title = {Experimental methods for investigating the formation of flow patterns in a very wide gap Taylor-Couette flow (\$\eta=0.1\$)}, series = {tm - Technisches Messen}, volume = {90}, journal = {tm - Technisches Messen}, number = {5}, issn = {2196-7113}, doi = {10.1515/teme-2022-0107}, pages = {332 -- 339}, language = {en} } @misc{GaillardSzaboEgbers, author = {Gaillard, Yann and Szabo, Peter and Egbers, Christoph}, title = {AtmoFlow: Thermo-electrohydrodynamic convection in the thermally driven spherical shell with differential rotation}, series = {EGU General Assembly 2023}, journal = {EGU General Assembly 2023}, doi = {10.5194/egusphere-egu23-1841}, 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} } @misc{HasanuzzamanEgbers, author = {Hasanuzzaman, Gazi and Egbers, Christoph}, title = {Application of machine learning for sustainable aviation : the role of friction drag and flow control in turbulent boundary layer flows}, series = {The 2nd International Conference on Advancing Sustainable Futures (ICASF 2024)}, journal = {The 2nd International Conference on Advancing Sustainable Futures (ICASF 2024)}, doi = {10.13140/RG.2.2.31060.92807}, pages = {1 -- 8}, language = {en} } @misc{SimonYaraslauSzaboetal., author = {Simon, K{\"u}hne and Yaraslau, Sliavin and Szabo, Peter and Carter, R. and Krebs, Andreas and Egbers, Christoph}, title = {Simultaneous particle image velocimetry and background oriented schlieren measurements of convective flows}, series = {Experimentelle Str{\"o}mungsmechanik, Hrsg.: B. Ruck et al.}, journal = {Experimentelle Str{\"o}mungsmechanik, Hrsg.: B. Ruck et al.}, publisher = {German Association for Laser Anemometry 26.8 GALA e.V.}, address = {Karlsruhe}, isbn = {978-3-9816764-4-0}, language = {en} } @misc{KuehneSliavinSzaboetal., author = {K{\"u}hne, Simon and Sliavin, Yaraslau and Szabo, Peter and Carter, Richard and Krebs, Andreas and Egbers, Christoph}, title = {Phase-demodulation of interferograms of thermo-electrohydrodynamic convection in a differentially heated cylindrical annulus}, series = {Experimentelle Str{\"o}mungsmechanik : 31. Fachtagung, 3.-5. September 2024, Berlin / Herausgeber: C. Rauh, B. Ruck, A. Leder}, journal = {Experimentelle Str{\"o}mungsmechanik : 31. Fachtagung, 3.-5. September 2024, Berlin / Herausgeber: C. Rauh, B. Ruck, A. Leder}, publisher = {German Association for Laser Anemometry 26.8 GALA e.V.}, address = {Karlsruhe}, isbn = {978-3-9816764-4-0}, pages = {7.1. -- 7.8}, language = {en} } @misc{ShahirpourEgbersSesterhenn, author = {Shahirpour, Amir and Egbers, Christoph and Sesterhenn, J{\"o}rn}, title = {Detection of energetic low dimensional subspaces in spatio-temporal space in turbulent pipe flow}, series = {Springer Nature}, journal = {Springer Nature}, number = {Volume 114}, doi = {10.1007/s10494-024-00600-z}, pages = {1017 -- 1041}, language = {en} } @misc{SzaboEgbers, author = {Szabo, Peter and Egbers, Christoph}, title = {Dielectrophoretic-driven thermoelectrohydrodynamic convection in a dielectric fluid layer induced by an inhomogeneous external electric field}, series = {Physical review E}, volume = {111}, journal = {Physical review E}, publisher = {American Physical Society}, address = {College Park, MD}, issn = {2470-0053}, doi = {10.1103/PhysRevE.111.045105}, pages = {1 -- 9}, language = {en} } @misc{TravnikovSzaboGaillardetal., author = {Travnikov, Vadim and Szabo, Peter and Gaillard, Yann and Egbers, Christoph}, title = {Centrifugally-driven spherical gap convection with polar angle-dependent boundary condition : can the Nusselt number fall below unity?}, series = {Physics of fluids}, volume = {37}, journal = {Physics of fluids}, publisher = {American Institute of Physics}, address = {New York}, issn = {1089-7666}, doi = {10.1063/5.0281082}, pages = {1 -- 15}, language = {en} } @misc{BarzantnyHamedeMajchrzyketal., author = {Barzantny, Marcel and Hamede, Mohammed Hussein and Majchrzyk, MichaΕ‚ and Merbold, Sebastian and Egbers, Christoph and Kostowski, Wojciech}, title = {Experimental investigation of the flow characteristics driving the Ranque-Hilsch phenomenon}, series = {International journal of heat and mass transfer}, volume = {253}, journal = {International journal of heat and mass transfer}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {0017-9310}, doi = {10.1016/j.ijheatmasstransfer.2025.127543}, pages = {1 -- 14}, abstract = {The Ranque-Hilsch vortex tube (RHVT) is a device that separates a pressurized inlet stream into two decompressed streams of different temperature, flowing to the so-called hot and cold outlets. In this study, the flow structures within the vortex tube were examined qualitatively. The examination considered both compressible and incompressible fluids, using pressurized air and water as working fluids. A parametric study was conducted, in which the fluid inlet pressure and the vortex tube length were varied. Three tubes, with the same diameter but differing lengths (100, 180, and 240 mm) were utilized. The flow inside the tube was investigated using a flow visualization technique, which was employed in a variety of configurations and setups contingent on the specific fluid conditions under examination. The visualization process required the use of aerosol injection in the case of air, and kalliroscope particles in the case of water investigation. The research enabled the visualization of the flow structure within the vortex tube, thereby significantly advancing the comprehension of the underlying physical processes. The findings of the experimental research demonstrated the existence of phenomena of considerable scientific value. The internal vortex and its spatial and temporal structure observed in the RHVT were consistent with literature data. This was achieved despite the so-far established consensus that this type of research is challenging and not entirely reliable. In the course of water-based investigation, the cavitation phenomenon was observed in the vicinity of the internal vortex. This discovery is likely to be the first of its kind and may contribute significantly to the advancement of research on the Ranque-Hilsch phenomenon.}, language = {en} } @misc{ZanounBauerWagneretal., author = {Zanoun, El-Sayed and Bauer, Christian and Wagner, Claus and Durst, Franz and Egbers, Christoph and Bellani, Gabriele and Talamelli, Alessandro}, title = {Cross-validation of numerical and experimental data in turbulent pipe flow with new scaling correlations}, series = {Journal of turbulence}, journal = {Journal of turbulence}, publisher = {Taylor \& Francis}, address = {London}, doi = {10.1080/14685248.2025.2560314}, pages = {1 -- 22}, abstract = {The dependence of turbulence statistics and wall friction on Reynolds number in fully developed turbulent pipe flow remains a fundamental subject in fluid mechanics. This paper cross-validates experimental and numerical results, focusing on the scaling of turbulence statistics at the pipe centerline and across the inner-outer flow region. Pipe flow experiments were reviewed for friction Reynolds numbers 810≀Reπœβ‰€55Γ—103, where Re𝜏=π‘’πœβ’π‘…/𝜈, π‘’πœ is the wall friction velocity, 𝑅 the pipe radius, and 𝜈 the kinematic viscosity. Complementary DNS data for 180≀Reπœβ‰€2880 provide detailed insight into near-wall turbulence. A novel friction correlation, Re𝜏=0.048Re0.923 c is introduced, predicting pipe-wall friction across a wide range of Re𝑐 with accuracy better than Β±2.06\%, where Re𝑐 is the Reynolds number based on the centerline streamwise mean velocity component π‘ˆzc. This correlation enables reliable friction estimates from centerline single-point measurements or DNS data without requiring near-wall or streamwise pressure-gradient information and is validated by consistent agreement with both experiments and DNS. The monotonic decrease in centerline turbulence intensity βŸ¨π‘’β€²π‘§2⟩1/2/π‘ˆzc with increasing Re𝑐 is explained using the streamwise mean momentum equation. Finally, azimuthal spatial filtering of DNS data highlights the limitations of hot-wire resolution near the wall. For Re𝜏β‰₯2880, higher-order experimental statistics agree well with DNS for 𝑦+β‰₯30 and into the logarithmic region, with both datasets equally well described by logarithmic or power-law correlations, while near-wall discrepancies remain due to resolution limits.}, language = {en} }