TY - GEN A1 - Borcia, Rodica A1 - Borcia, Ion-Dan A1 - Bestehorn, Michael A1 - Sharma, Deewakar A1 - Amiroudine, Sakir T1 - Phase field modeling in liquid binary mixtures: isothermal and non-isothermal problems T2 - Physical Review Fluids N2 - The objective in the present paper is to study binary fluids with phase field modeling coupled with Navier-Stokes equations. An extended free energy is proposed to account for the continuous path from immiscible to miscible states. We consider fluid pairs that are immiscible for temperatures below the critical one (consolute temperature) and miscible above it. Our extended phase field equation permits us to move from the immiscible state (governed by the Cahn-Hilliard equation) to the miscible state (defined by the species diffusion equation). The scaling of interface tension and interface width with the distance to the critical point is highlighted. The whole system is mechanically excited showing Faraday instability of a flat interface. A linear stability analysis is performed for the stable case (interface waves) as well as for the unstable Faraday one. For the latter, a Floquet analysis shows the well-known Arnold's tongues as a function of the consolute temperature and depth layer. Moreover, two-dimensional finite difference simulations have been performed allowing us to model nonlinear flow patterns both in miscible and immiscible phases. Linear theory and nonlinear simulations show interesting results such as the diminishing of the wavelength of Faraday waves or a shift of the critical vibration amplitude when the consolute temperature is approached. KW - Binary fluids KW - Drop coalescence KW - Drop interactions KW - Drops & bubbles KW - Microfluidics Y1 - 2022 UR - https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.7.064005 U6 - https://doi.org/10.1103/PhysRevFluids.7.064005 SN - 2469-990X VL - 7 IS - 6 SP - 1 EP - 19 ER - TY - GEN A1 - Borcia, Rodica A1 - Popescu, Sebastian A1 - Borcia, Ion-Dan T1 - IMA10: interfacial fluid dynamics and processes T2 - European Physical Journal Special Topics N2 - MA10–special issue presents recent advances on interfacial fluid dynamics with applications in microfluidics, biology, engineering and geophysics. KW - Fluid Dynamics KW - Instabilities Droplets Y1 - 2023 U6 - https://doi.org/10.1140/epjs/s11734-023-00798-5 SN - 1951-6401 SN - 1951-6355 VL - 232 IS - 4 SP - 365 EP - 366 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 - GEN A1 - Bestehorn, Michael A1 - Borcia, Ion-Dan T1 - Thin film lubrication dynamics of a binarymixture Y1 - 2010 ER - TY - CHAP A1 - Borcia, Ion-Dan A1 - Harlander, Uwe T1 - Inertial waves inside a liquid confined between two rotating coaxial cylinders: the case of small Ekman number Y1 - 2011 ER - TY - CHAP A1 - Borcia, Ion-Dan A1 - Seelig, Torsten A1 - Harlander, Uwe A1 - Egbers, Christoph T1 - Inertial waves in rotating cylindrical geometry: mean flow interactions and attractors Y1 - 2011 ER - TY - CHAP A1 - Borcia, Ion-Dan T1 - Attractors, eigenvalues and mean flow interactions in a fluid confined between two co-rotating cylinders Y1 - 2011 ER - TY - GEN A1 - Borcia, Ion-Dan A1 - Bestehorn, Michael T1 - Simulation of pattern morphology in binary liquid mixtures Y1 - 2010 ER - TY - CHAP A1 - Seelig, Torsten A1 - Harlander, Uwe A1 - Borcia, Ion-Dan A1 - Egbers, Christoph T1 - Zonal mean flow excitation due to inertial waves propagating in the meridional plane T2 - European Geosciences Union (EGU), 9th General Assembly, Vienna, Austria, 22-27 April Y1 - 2012 UR - http://meetingorganizer.copernicus.org/EGU2012/EGU2012-4981-1.pdf N1 - EGU2012-4981-1 ER - TY - CHAP A1 - Borcia, Ion-Dan A1 - Harlander, Uwe A1 - Seelig, Torsten A1 - Egbers, Christoph T1 - Comparing attractor frequency bands with eigen frequencies for a confined rotating fluid T2 - European Geosciences Union (EGU), 9th General Assembly, Vienna, Austria, 22-27 April Y1 - 2012 UR - http://meetingorganizer.copernicus.org/EGU2012/EGU2012-10411.pdf N1 - EGU2012-10411 ER - TY - CHAP A1 - Borcia, Ion-Dan A1 - Harlander, Uwe A1 - Seelig, Torsten A1 - Egbers, Christoph T1 - Comparing the spectrum of wave attractor frequency bands and the eigenspectrum of fluid in a rotating annulus with inclined inner cylinder T2 - Book of abstracts, 9th European Fluid Mechanics Conference (EFMC), 9-13 September, Rome, Italy Y1 - 2012 UR - http://www.efmc9.eu/absbook/index.html ER - TY - CHAP A1 - Seelig, Torsten A1 - Harlander, Uwe A1 - Borcia, Ion-Dan A1 - Scurtu, Nicoleta A1 - Egbers, Christoph A1 - Klein, Marten A1 - Ghasemi, Abouzar A1 - Will, Andreas A1 - Schaller, Eberhard T1 - Inertial waves in rotating cylindrical annulus: theory, experiment and simulations T2 - Book of abstracts, 9th European Fluid Mechanics Conference (EFMC), 9-13 September, Rome, Italy Y1 - 2012 UR - http://www.efmc9.eu/absbook/index.html ER -