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On streamwise structures in boundary layer under adverse pressure gradient on inclined plate

Uruba V., Prochazka P., Skala V.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2018

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Vol. 22, No 3

255--267

EN

The presented study is focused on experimental investigation of a boundary layer on a flat plate in an adverse pressure gradient. The flat plate is placed in a regular flow, the pressure gradient is generated by the plate inclination. The preceding studies deal with the structure of the wake behind the plate, the presented study concentrates on the flow structureclose to the suction surface of the plate. The dynamical behavior of the flow structures is studied in details with respect to the topology in the streamwise direction. In spite of the fact that thetime-mean flow field is close to 2D, more or less constant along the span, the instantaneous structures topology is fully 3D. Rather oblique structures are detected instead of those oriented in the streamwise direction. The patterns are travelling in the streamwise direction along the plate.

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Zastosowanie techniki termoanemometrycznej w badaniach modelowych nad rozprzestrzenianiem zanieczyszczeń gazowych

Moryń-Kucharczyk E., Jonas P., Mazur. O., Podolski M., Uruba V.

Systems : journal of transdisciplinary systems science

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2006

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Vol. 11, nr 1

247-254

EN

Simultaneous measurement of velocity and concentration in flow of two gases mixture is required at several wind tunnel experiments, e.g. modeling of pollutant dispersion. A thermoanemometer is a suitable tool for such measurements owing to it broad dynamic range for measurement of velocity and concentration fluctuations. The paper presents a measurement method by means of a special dual hot-wire probe (modification of the DANTEC t. 55P71) in a stream of the air/CO2 mixture. The in-house developed procedure of the simultaneous measurement of both the mean and the r.m.s. values of concentration and velocity was applied to investigation of a gaseous carbon dioxide round jet spreading into a collateral air flow. Performed experiments indicate that the applied measurement method might be useful for the turbulent diffusion investigations in complex conditions. They also confirm the usability of carbon dioxide as a tracer gas in modeling of gaseous pollutant spreading.

3

The improvement of the hot-wire anemometer measurement procedure in the LP stage a full scale steam turbine

Jonas P., Mazur O., Rehak V., Uruba V.

Transactions of the Institute of Fluid-Flow Machinery

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2003

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nr 113

191-200

EN

The method of investigation of the flow structure and correlation velocity/temperature fields in the LP stage using a CTA anemometer is outlined in the contribution. The arrangement of the rotary slanted hot-wire probe equipped with a resistance thermometer and a pressure transducer is described that makes possible to correct the CTA-readings from the effect of the steam state small variations and from the disturbances caused by the impacts of large water droplets on the heated wire. Next some details of the synchronized sampling of CTA output voltage and the evaluation of the results are presented.

4

Investigation of the intermittency factor in a transitional boundary layer near the wall

Jonas P., Mazur O., Uruba V., Stępień M.

Turbulence : international journal

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2002

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Vol. 8-9

189-198