Abstract
We present an experimental study focusing on the large- and small-scale structures in turbulent mixed convection. Measurements are conducted at stable conditions and during a reconfiguration event using temperature probes and triggered stereoscopic particle image velocimetry. It is found that the amplitude of the temperature distribution is higher for a state with three Large-Scale Circulations (LSC) than for a state with four LSCs. Furthermore, a correlation analysis of velocity fields measured during a reconfiguration process reveals the change of the dominant LSC mode. However, the mean spatial power distribution computed via a fast Fourier transformation reflects no changes in small-scale flow structures.
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Acknowledgments
The authors like to thank Annika Köhne for proof-reading this work.
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Niehaus, K.A., Mommert, M., Schiepel, D., Schmeling, D., Wagner, C. (2020). Comparison of Two Unstable Flow States in Turbulent Mixed Convection. In: Dillmann, A., Heller, G., Krämer, E., Wagner, C., Tropea, C., Jakirlić, S. (eds) New Results in Numerical and Experimental Fluid Mechanics XII. DGLR 2018. Notes on Numerical Fluid Mechanics and Multidisciplinary Design, vol 142. Springer, Cham. https://doi.org/10.1007/978-3-030-25253-3_52
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DOI: https://doi.org/10.1007/978-3-030-25253-3_52
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