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 - TY - CHAP A1 - Seelig, Torsten A1 - Borcia, Ion-Dan A1 - Klein, Marten A1 - Ghasemi, Abouzar A1 - Will, Andreas A1 - Egbers, Christoph A1 - Schaller, Eberhard A1 - Harlander, Uwe T1 - Inertial waves and wave attractors in a rotating annulus with inner or outer cylinder libration T2 - European Geosciences Union (EGU), 10th General Assembly, Vienna, Austria, 07 – 12 April 2013 Y1 - 2013 UR - http://meetingorganizer.copernicus.org/EGU2013/EGU2013-7602.pdf N1 - EGU2013-7602 ER - TY - GEN A1 - Borcia, Ion-Dan A1 - Harlander, Uwe T1 - Inertial waves in a rotating annulus with inclined inner cylinder: comparing the spectrum of wave attractor frequency bands and the eigenspectrum in the limit of zero inclination T2 - Theoretical and Computational Fluid Dynamics Y1 - 2013 U6 - https://doi.org/10.1007/s00162-012-0278-6 SN - 1432-2250 VL - 27 IS - 3-4 SP - 397 EP - 413 ER - TY - GEN A1 - Klein, Marten A1 - Seelig, Torsten A1 - Kurgansky, Michael V. A1 - Ghasemi, Abouzar A1 - Borcia, Ion-Dan A1 - Will, Andreas A1 - Schaller, Eberhard A1 - Egbers, Christoph A1 - Harlander, Uwe T1 - Inertial wave excitation and focusing in a liquid bounded by a frustum and a cylinder T2 - Journal of Fluid Mechanics N2 - The mechanism of localized inertial wave excitation and its efficiency is investigated for an annular cavity rotating with Ω0 . Meridional symmetry is broken by replacing the inner cylinder with a truncated cone (frustum). Waves are excited by individual longitudinal libration of the walls. The geometry is non-separable and exhibits wave focusing and wave attractors. We investigated laboratory and numerical results for the Ekman number E ≈ 10−6. inclination α = 5.71◦ and libration amplitudes ε 0.2 within the inertial wave band 0 < ω < 2Ω0 . Under the assumption that the inertial waves do not essentially affect the boundary-layer structure, we use classical boundary-layer analysis to study oscillating Ekman layers over a librating wall that is at an angle α = 0 to the axis of rotation. The Ekman layer erupts at frequency ω = f∗, where f∗ ≡ 2Ω0 sin α is the effective Coriolis parameter in a plane tangential to the wall. For the selected inclination this eruption occurs for the forcing frequency ω/Ω0 = 0.2. For the librating lids eruption occurs at ω/Ω0 = 2. The study reveals that the frequency dependence of the total kinetic energy Kω of the excited wave field is strongly connected to the square of the Ekman pumping velocity wE (ω) that, in the linear limit, becomes singular when the boundary layer erupts. This explains the frequency dependence of non-resonantly excited waves. By the localization of the forcing, the two configurations investigated, (i) frustum libration and (ii) lids together with outer cylinder in libration, can be clearly distinguished by their response spectra. Good agreement was found for the spatial structure of low-order wave attractors and periodic orbits (both characterized by a small number of reflections) in the frequency windows predicted by geometric ray tracing. For ‘resonant’ frequencies a significantly increased total bulk energy was found, while the energy in the boundary layer remained nearly constant. Inertial wave energy enters the bulk flow via corner beams, which are parallel to the characteristics of the underlying Poincaré problem. Numerical simulations revealed a mismatch between the wall-parallel mass fluxes near the corners. This leads to boundary-layer eruption and the generation of inertial waves in the corners. KW - boundary-layer structure KW - geophysical and geological flows KW - waves in rotating fluids Y1 - 2014 U6 - https://doi.org/10.1017/jfm.2014.304 SN - 1750-6859 IS - vol. 751 SP - 255 EP - 297 ER - TY - CHAP A1 - Klein, Marten A1 - Ghasemi, Abouzar A1 - Seelig, Torsten A1 - Borcia, Ion-Dan A1 - Harlander, Uwe A1 - Will, Andreas T1 - DNS of inertial wave attractors in a librating annulus with height-dependent gap width T2 - 15th European turbulence conference (ETC), Delft, The Netherlands (2015) N2 - Direct numerical simulations (DNS) of inertial wave attractors have been carried out in a librating Taylor-Couette system with broken mirror symmetry in the radial-axial cross-section. The inertial wave excitation mechanism and its localisation at the edges was clarified by applying boundary layer theory. Additional resonance peaks in the simulated response spectra were found to agree with low-order wave attractors obtained by geometric ray tracing. Numerics and theory are in qualitative agreement with recent lab experiments. KW - direct numerical simulations KW - geophysical and astrophysical turbulence KW - waves in rotating fluids Y1 - 2015 UR - http://www.etc15.nl/proceedings/proceedings/documents/134.pdf ER - TY - CHAP A1 - Klein, Marten A1 - Ghasemi, Abouzar A1 - Seelig, Torsten A1 - Borcia, Ion-Dan A1 - Harlander, Uwe A1 - Will, Andreas T1 - Mean flow generation and inertial wave attractors in a librating annulus: DNS and theory T2 - European Geosciences Union, General Assembly 2015, Vienna, Austria, 13 April - 17 May 2015 KW - boundary-layer structure KW - direct numerical simulation KW - instability KW - waves in rotating fluids Y1 - 2015 UR - http://meetingorganizer.copernicus.org/EGU2015/EGU2015-15640-1.pdf N1 - EGU2015-15640-1 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Klein, Marten A1 - Ghasemi, Abouzar A1 - Seelig, Torsten A1 - Borcia, Ion-Dan A1 - Harlander, Uwe A1 - Will, Andreas T1 - DNS of inertial wave attractors in a librating annular cavity with a height-dependent gap T2 - ICTW 19, Book of Abstracts, 19th International Couette-Taylor Workshop, June 24 - 26, 2015 Cottbus, Germany KW - waves in rotating fluids KW - geophysical and geological flows KW - direct numerical simulations Y1 - 2015 SP - 122 EP - 123 CY - Cottbus ER - TY - CHAP A1 - Klein, Marten A1 - Borcia, Ion-Dan A1 - Egbers, Christoph A1 - Ghasemi, Abouzar A1 - Harlander, Uwe A1 - Kurgansky, Michael V. A1 - Schaller, Eberhard A1 - Seelig, Torsten A1 - Will, Andreas T1 - Inertial Waves and Wave Excitation Mechanisms in Annular Cavities: Simulations, Experiments and Theory T2 - European Turbulence Conference ETC14, Lyon, 2013 KW - boundary-layer structure KW - geophysical and geological flows KW - waves in rotating fluids Y1 - 2013 UR - http://etc14.ens-lyon.fr/etc-14-proceedings/accepted-talks ER - TY - CHAP A1 - Rodda, Costanza A1 - Borcia, Ion-Dan A1 - Harlander, Uwe T1 - Experimental study of internal wave emission from baroclinic jets T2 - 11th European Fluid Mechanics Conference, Sept. 12-16, 2016, Sevilla, Spain Y1 - 2016 UR - http://www.efmc11.org/download/com/com_0145_C1CLR1.pdf ER - TY - CHAP A1 - Rodda, Costanza A1 - Borcia, Ion-Dan A1 - Harlander, Uwe T1 - Experimental results on intertia gravity wave emission from baroclinic jets T2 - Book of abstracts, School ISTROF 2016, Instabilities and Turbulence in Strato-Rotational Flows, July 11-13th, 2016, Le Havre Y1 - 2016 UR - https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxzY2hvb2xpc3Ryb2Z8Z3g6NDA3Y2E3ZGQ2OWIwMTdmNQ ER - TY - GEN A1 - Vincze, Miklós A1 - Borcia, Ion-Dan A1 - Harlander, Uwe T1 - Temperature fluctuations in a changing climate: an ensemble-based experimental approach T2 - Scientific Reports Y1 - 2017 U6 - https://doi.org/10.1038/s41598-017-00319-0 SN - 2045-2322 VL - 7 SP - 254 ER - TY - CHAP A1 - Rodda, Costanza A1 - Borcia, Ion-Dan A1 - Harlander, Uwe T1 - Baroclinic wave laboratory experiment with radial heating and vertical stratification to study IGW emission from baroclinic fronts T2 - European Geosciences Union General Assembly 2017 Vienna, Austria, 23–28 April 2017 Y1 - 2017 UR - http://meetingorganizer.copernicus.org/EGU2017/EGU2017-3676.pdf N1 - EGU2017-3676 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - GEN A1 - Rodda, Costanza A1 - Borcia, Ion-Dan A1 - Le Gal, Patrice A1 - Vincze, Miklos A1 - Harlander, Uwe T1 - Baroclinic, Kelvin and inertia-gravity waves in the barostrat instability experiment T2 - Geophysical & Astrophysical Fluid Dynamics Y1 - 2018 U6 - https://doi.org/10.1080/03091929.2018.1461858 SN - 1029-0419 SN - 0309-1929 VL - 112 IS - 3 SP - 175 EP - 206 ER -