Abstract
The flow features of mixed convection flow in the presence of a cylindrical roughness element are investigated in a horizontal laminar flat-plate flow inside a water channel by means of Temperature-Sensitive Paint (TSP). The buoyancy forces are generated by partially heating the flat plate, however, the beginning of the flat plate is adiabatic. A cylindrical roughness element is positioned at the start of the heated part of the test section. Different ratios of forced and free convection, which form the mixed convection flow, are investigated by adjusting the free stream velocity and the heating power. Thereby, the Reynolds number is varied in the range of \( 398 \le {\text{Re}}_{\text{k}} \le 1195 \), while the Grashof number reaches values between \( 3.97 \cdot 10^{8} \le {\text{Gr}} \le 1.46 \cdot 10^{9} \). This leads to Richardson numbers of \( 0.53 \le {\text{Ri}} \le 7.72 \).
For an increasing Reynolds number and a decreasing Grashof number, the onset of longitudinal vortices is shifted downstream while their spanwise wavelength is increased. The wake of the element changes from a well-organized, laminar flow into a turbulent flow which is accompanied with a broadening of the wake. An interaction between the wake and the vortices is observed for some conditions. In addition, this study reveals that the Richardson number is not a suitable measure for predicting the flow features of the investigated configurations.
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References
Gilpin, R.R., Imura, H., Cheng, K.C.: Experiments on the onset of longitudinal vortices in horizontal blasius flow heated from below. J. Heat Transf. 100(1), 71–77 (1978)
Lin, T.F.: Buoyancy driven vortex flow and thermal structures in a very low reynolds number mixed convective gas flow through a horizontal channel. Int. J. Heat Fluid Flow 24(3), 299–309 (2003)
Bhattacharyya, S., Mahapatra, S.: Vortex shedding around a heated square cylinder under the influence of buoyancy. Heat Mass Transf. 41(9), 824–833 (2005)
Biswas, G., Laschefski, H., Mitra, N.K., Fiebig, M.: Numerical investigation of mixed convection heat transfer in a horizontal channel with a built-in square cylinder. Numercial Heat Transf. 18(2), 173–188 (1990)
Moulai, S., Korichi, A., Fohanno, S., Polidori, G.: Buoyancy-assisted mixed convection flow over a heated square cylinder in a vertical channel. In: International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics (2014)
Farouk, B., Güceri, S.: Natural and mixed convection heat transfer around a horizontal cylinder within confining walls. Numerical Heat Transf. Part A Appl. 5(3), 329–341 (1982)
Fransson, J.H.M., Brandt, L., Talamelli, A., Cossu, C.: Experimental and theoretical investigation of the nonmodal growth of steady streaks in a flat plate boundary layer. Phys. Fluids 16(10), 3627–3638 (2004)
Puckert, D.K., Rist, U.: Experiments on critical Reynolds number and global instability in roughness-induced laminar–turbulent transition. J. Fluid Mech. 844, 878–904 (2018)
Tropea, C., Yarin, A.L., Foss, J.F. (eds.): Chap. 7.4 transition-detection by temperature-sensitive paint. Springer Handbook of Experimental Fluid Mechanics, Springer, Berlin Heidelberg (2007)
Lemarechal, J., Mäteling, E., Klein, C., Puckert, D.K., Rist, U.: Reattaching flow behind a forward-backward facing step investigated with temperature-sensitive paint. In: New Results in Numerical and Experimental Fluid Mechanics XI: Contributions to the 20th STAB/DGLR Symposium Braunschweig, pp. 285–293, Springer, Germany (2018)
Fey, U., Klein, C., Möller, T.J., Pöttner, J., Radespiel, R., Ondrus, V., Beifuß, U.: Investigation of circular cylinder flow in water using temperature-sensitive paint. In: New Results in Numerical and Experimental Fluid Mechanics VIII: Contributions to the 17th STAB/DGLR Symposium Berlin, pp. 657–664, Springer, Germany (2013)
Dittmann, A., Fischer, S., Huhn, J., Klinger, J.: Repetitorium der Technischen Thermodynamik. Springer, Wiesbaden (2013)
Puckert, D.K., Dieterle, M., Rist, U.: Reduction of freestream turbulence at low velocities. Exp. Fluids 58(5), 45 (2017)
Wiegand, T.: Experimentelle Untersuchungen zum laminar turbulenten Transitionsprozess eines Wellenzugs in einer Plattengrenzschicht. Ph.D thesis, Universität Stuttgart (1996)
Ondrus, V., Meier, R.J., Klein, C., Henne, U., Schaeferling, M., Beifuss, U.: Europium 1,3-di(thienyl)propane-1,3-diones with outstanding properties for temperature sensing. Sens. Actuators, A 233, 434–441 (2015)
Gregory, N.T., Walker, W.S.: The effect on transition of isolated surface excrescences in the boundary layer. HM Stationery Office (1956)
Lemarechal, J., Mäteling, E., Klein, C., Puckert, D.K., Rist, U.: Visualization of near-wall structures of an isolated cylindrical roughness element in a laminar boundary layer without pressure gradient. In: 21st STAB/DGLR Symposium Darmstadt, Germany (2018)
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Mäteling, E., Lemarechal, J., Klein, C., Puckert, D.K., Rist, U. (2020). Experimental Investigation of Mixed Convection in Horizontal Channel Flow in Combination with Cylindrical Roughness Elements. 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_51
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