TY - CHAP A1 - Borcia, Ion-Dan A1 - Borcia, Rodica A1 - Bestehorn, Michael A1 - Borcia, C. A1 - Dumitrascu, N. A1 - Egbers, Christoph T1 - Drops on cylindrical surfaces T2 - 7th Conference of the International Marangoni Association, Vienna (Austria), June 23-26, 2014 Y1 - 2014 UR - http://ima7.conf.tuwien.ac.at/AbstractsIMA7.pdf SP - S. 33 PB - Techn. Univ. CY - Vienna ER - TY - CHAP A1 - Borcia, Ion-Dan A1 - Borcia, Rodica A1 - Bestehorn, Michael A1 - Egbers, Christoph T1 - Drops on cylindrical wires T2 - International Topical Team Workshop on Two-Phase Systems for Ground and Space Applications, ITTW 2013 Y1 - 2013 UR - http://www.zarm.uni-bremen.de/ITTW2013/abstracts/ITTW2013_Book-of-Abstracts.pdf ER - TY - GEN A1 - Borcia, Rodica A1 - Borcia, Ion-Dan A1 - Helbig, Markus A1 - Meier, Martin A1 - Egbers, Christoph A1 - Bestehorn, Michael T1 - Dancing drops over vibrating substrates T2 - The European Physical Journal Special Topics KW - Thin Film Instabilities Y1 - 2017 UR - https://link.springer.com/article/10.1140/epjst/e2016-60202-6 U6 - https://doi.org/10.1140/epjst/e2016-60202-6 SN - 1951-6355 SN - 1951-6401 VL - 226 IS - 6 SP - 1297 EP - 1306 ER - TY - CHAP A1 - Borcia, Ion-Dan A1 - Borcia, Rodica A1 - Bestehorn, Michael A1 - Xu, Wenchao A1 - Harlander, Uwe T1 - Surface waves generated by libration in a circular channel T2 - The 12th European Fluid Mechanics Conference, 9 September 2018 – 13 September 2018, Vienna, Austria Y1 - 2018 UR - http://info.tuwien.ac.at/efmc12/EFMC12_program_v3.2.pdf ER - TY - GEN A1 - Borcia, Ion-Dan A1 - Borcia, Rodica A1 - Bestehorn, Michael A1 - Richter, Stefan A1 - Xu, Wenchao A1 - Harlander, Uwe T1 - Horizontal Faraday instability and parametric excitation in a circular channel T2 - GAMM 2019, 90th Annual Meeting of the International Assoociation of Applied Mathematics and Mechanics, February 18-22, 2019, Vienna, Austria Y1 - 2018 UR - https://jahrestagung.gamm-ev.de/images/2019/Photos/GAMM2019_BookofAbstracts.pdf SN - 978-3-903024-84-7 SP - 338 PB - TU Verlag CY - Wien ER - TY - GEN A1 - Borcia, Ion-Dan A1 - Borcia, Rodica A1 - Xu, Wenchao A1 - Bestehorn, Michael A1 - Richter, Sebastian A1 - Harlander, Uwe T1 - Undular bores in a large circular channel T2 - European Journal of Mechanics - B/Fluids N2 - An experimental device previously developed for studying rotating baroclinic flows has been used to investigate undular bores formation, propagation and collision. Up to our knowledge this is the first experimental study of undular bores in a circular channel. For a setup without barriers, this geometry accomplishes in a natural way the periodic lateral boundary conditions, very often used in numerical simulations. An excellent agreement between the experiment and simulation has been achieved. The spatio-temporal structure of bores is well reproduced for the first few reflections or collisions. KW - Undular bores KW - Bore collision KW - Periodical boundary conditions Y1 - 2020 UR - https://www.sciencedirect.com/science/article/pii/S0997754619300706?via%3Dihub U6 - https://doi.org/10.1016/j.euromechflu.2019.09.003 SN - 0997-7546 VL - 79 SP - 67 EP - 73 ER - TY - GEN A1 - Borcia, Ion-Dan A1 - Richter, Sebastian A1 - Borcia, Rodica A1 - Schön, Franz-Theo A1 - Harlander, Uwe A1 - Bestehorn, Michael T1 - Wave propagation in a circular channel: sloshing and resonance T2 - The European Physical Journal Special Topics N2 - Surface wave resonance of a liquid (water) layer confined in a circular channel is studied both experimentally and numerically. For the experiment, eight unevenly distributed ultrasonic distance sensors measure the local height of the wave surface. The resonance curves show maxima only for odd multiples of the fundamental resonance frequency . We explained this behavior using a simple intuitive “ping-pong” like model. Collision of wave fronts can be observed for higher frequencies. Also, the wave reflection on the walls can be treated as wave collision with itself. The non-linearity seems to be weak in our study so the delay in the wave propagation before and after the collision is small. Time-space plots show localized propagating waves with high amplitudes for frequencies near resonance. Between the peaks low amplitude and harmonic patterns are observed. However, for higher frequencies, the frequency band for localized waves becomes wider. In the Fourier space-time plane, this can be observed as a point for the harmonic patterns or a superposition of two lines: one line parallel to wave-vector k axis corresponding to the excitation frequency and a second line with inclination given by wave propagation velocity . For planned future work, this result will help us to reconstruct the whole water surface elevation using time-series from only a few measurement points Y1 - 2023 UR - https://link.springer.com/article/10.1140/epjs/s11734-023-00790-z U6 - https://doi.org/10.1140/epjs/s11734-023-00790-z SN - 1951-6401 SN - 1951-6355 VL - Vol. 232 IS - 4 SP - 461 EP - 468 ER - TY - GEN A1 - Schön, Franz-Theo A1 - Harlander, Uwe A1 - Borcia, Ion Dan A1 - Borcia, Rodica A1 - Bestehorn, Michael T1 - Mean fluid transport in an oscillating circular channel with asymmetric forcing T2 - Water waves : an interdisciplinary journal N2 - 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. Y1 - 2025 U6 - https://doi.org/10.1007/s42286-025-00121-w SN - 2523-3688 VL - 2025 SP - 1 EP - 21 PB - Birkhäuser, part of Springer Nature CY - Basel ER - TY - CHAP A1 - Borcia, Rodica A1 - Bestehorn, Michael A1 - Egbers, Christoph T1 - Surface effects at the mixing of two perfectly miscible components in a thin liquid film T2 - International Topical Team Workshop on Two-Phase Systems for Ground and Space Applications, ITTW 2013 Y1 - 2013 UR - http://www.zarm.uni-bremen.de/ITTW2013/abstracts/ITTW2013_Book-of-Abstracts.pdf ER -