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1

Direct numerical simulation of the Taylor–Couette flow with the asymmetric end-wall boundary conditions

Tuliszka-Sznitko E., Kiełczewski K.

Archives of Mechanics

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2016

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Vol. 68, nr 5

395--418

EN

In the paper the authors present the results obtained during a direct numerical simulation of the transitional Taylor–Couette flow in closed cavity. The spectral vanishing viscosity method is used to stabilize computations for higher Reynolds numbers. The Taylor–Couette flow is widely used for studying the primary pattern formation, transitional flows and fully turbulent flows. The Taylor–Couette flow is also important from engineering point of view: the results can be interesting for engineers dealing with gas turbines and axial compressors. In the paper the attention is focused on the influence of the end-wall boundary conditions on the flow structures and on statistics (i.e. the radial profiles of the angular velocity, angular momentum, torque, the Reynolds stress tensor components). The results are discussed in the light of experimental and numerical data published in literature (F. Wendt, Ing.-Arch., 4, 1933; H. Brauckmann, B. Eckhardt, J. Fluid Mech., 718, 2013).

2

Numerical Investigations of Taylor-Couette Flow Using DNS/SVV Method

Tuliszka-Sznitko E., Kiełczewski K.

Computational Methods in Science and Technology

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2015

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Vol. 21, No. 4

211--219

EN

In the paper the authors present the results obtained during a numerical investigation (Direct Numerical Simulation/ Spectral Vanishing Viscosity method – DNS/SVV) of a Taylor-Couette flow, i.e. the flow between two concentric disks and two concentric cylinders. The Taylor-Couette flow is one of paradigmatical systems in hydrodynamics, widely used for studying the primary instability, pattern formation, transitional flows and fully turbulent flows. Simultaneously, the flows in rotating cavities appear in numerous machines in the field of mechanics and chemistry, e.g., in cooling systems of gas turbines and axial compressors. In the paper, attention is focused on the laminar-turbulent transition region of the Taylor-Couette flow. The main purpose of the computations is to investigate the influence of different parameters (the aspect ratio, the end-wall boundary conditions, temperature gradient) on the flow structure and on flow characteristics.

3

Numerical study of the flow structure and heat transfer in rotating cavity with and without jet

Kiełczewski K., Tuliszka-Sznitko E.

Archives of Mechanics

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2013

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Vol. 65, nr 6

527--548

EN

In the paper we investigate the flow with heat transfer in the rotating cavity of different geometrical parameters and different Reynolds numbers. We focus on the near-wall characteristics and compare our results with the experimental and numerical data published in literature as well as with the theoretical results. We also present the preliminary results obtained for rotor/rotor configurations with the axial annular jet. Computations are performed using pseudo-spectral methods. Parallelization of the DNS code allows us to perform computations on the meshes with up to 35 million collocation points.

4

Numerical simulation of turbulent heat and momentum transport in rotating cavity

Tuliszka-Sznitko E., Majchrowski W., Kiełczewski K.

Journal of Theoretical and Applied Mechanics

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2011

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Vol. 49 nr 4

1217-1232

EN

The paper gives the results of the Direct Numerical Simulation (DNS) and Large Eddy simulation (LES) which were performed to investigate the 3D transitional non-isothermal flows within a rotor/stator cavity. A Lagrangean version of the dynamic Smagorinsky eddy viscosity model was used. Computations were performed for the cavity of the aspect ratio L=3.0-5.0, curvature parameters Rm=1.8-5.0, for the Reynolds number Re=(1.0-2.5)105 and for defferent Prandtl numbers. The results were obtained for coupled momentum and thermal transport in the rotor/stator cavity flows. The obtained distributions of the turbulent heat flux tensor components, the Reynolds stress tensor components, the turbulent Prandtl numer and other structural parameters coincide with the experimental data (published in the literature).

PL

W atykule przedstawiono wyniki symulacji przepływu (z wymianą ciepła) w obszarze pomiędzy stojanem i wirnikiem oraz dwoma pierścieniami uzyskane z zastosowaniem metod DNS i LES. Badania przeprowadzono dla rozciagłości obszaru L=3.0-5.0 oraz dla współczynnika krzywizny Rm=1.8-5.0. Badano struktury niestabilnościowe występujące w warstwie przyściennej wirnika i stojana oraz profile osiowe naprężeń reynoldsowskich, fluktuacji temperatury, turbulentnej liczby Prandtla, profile parametrów strukturalnych i korelacyjnych. Obliczenia przeprowadzono dla różnych liczb Reynoldsa i Prandtla. Uzyskane rozwiązania porównano z wynikami badań eksperymentalnych Elkinsa i Eatona (2000) uzyskanymi podczas badania przepływu wokół pojedynczego wirującego dysku podgrzewanego jednorodnym strumieniem. Rezultaty badań porównywano również z wynikami uzyskanymi dla dwuwymiarowych turbulentnych warstw przyściennych.