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arXiv · 2012.06055

SPH modeling of natural convection around a heated horizontal cylinder: A comparison with experiments

F. Aragón·J. E. V. Guzmán·L. Di G. Sigalotti·J. Klapp·C. E. Alvarado-Rodríguez·I. Carvajal-Mariscal·A. R. Uribe-Ramírez
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Abstract

An experimental and numerical smoothed particle hydrodynamics (SPH) analysis was performed for the convective flow arising from a horizontal, thin cylindrical heat source enclosed in a glycerin-filled, slender enclosure at low Rayleigh numbers ($1.18\leq {\rm Ra}\leq 242$). Both the experiments and the SPH calculations were performed for positive ($0.1\leq\Delta T\leq 10$ K) and negative ($-10\leq\Delta T\leq -0.1$ K) temperature differences between the source and the surrounding fluid. In all cases a pair of steady, counter-rotating vortices is formed, accompanied by a plume of vertically ascending flow just above the source for $\Delta T>0$ and a vertically descending flow just below the source for $\Delta T<0$. The maximum flow velocities always occur within the ascending/descending plumes. The SPH predictions are found to match the experimental observations acceptably well with root-mean-square errors in the velocity profiles of the order of $\sim 10^{-5}$ m s$^{-1}$. The fact that the SPH method is able to reveal the detailed features of the flow phenomenon demonstrates the correctness of the approach.

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F. Aragón, J. E. V. Guzmán, L. Di G. Sigalotti, J. Klapp, C. E. Alvarado-Rodríguez, I. Carvajal-Mariscal, A. R. Uribe-Ramírez. 2020-12-11. SPH modeling of natural convection around a heated horizontal cylinder: A comparison with experiments. https://arxiv.org/abs/2012.06055

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