Behavior of settling inertial particles in a differentially heated cubic cavity at moderate Rayleigh number
This study is related to the transport of inertial particles in a differentially heated cubic cavity. Three moderate values of the Rayleigh number Ra = 2×108, 4×108, 7×108 are considered. There is no back reaction from the particle on the flow, i.e., one-way coupling. Small (d = 15μm), intermediate (d = 35μm), and large (d = 75 μm) sizes of particles are used to study the particle behavior. The particles are influenced by two forces, the drag and gravity force. From our simulations, we observed that a large fraction of smallsized particles follow the flow motion and they are not significantly affected by gravity, remaining suspended in the flow. On the other hand, large-sized particles quickly settle down toward the bottom wall under gravity and are deposited at the bottom wall. Owing to this difference, particle distribution for small particles and large particles is quite different. Small particles tend to accumulate near a particular region near hot and cold walls, while the particle depletion region is observed in the core region in a particular pattern. Large particles are almost uniformly distributed. Detailed mechanisms are discussed using the flow field and particle response characteristics.
KeywordsNatural convection One-way coupling Particle trajectory Rayleigh number
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- A. Sergent, S. Xin, P. Joubert, P. Le Quéré, J. Salat and F. Penot, Resolving the stratification discrepancy of turbulent natural convection in differentially heated air-filled cavities-Part I: Reference solutions using Chebyshev spectral methods, International Journal of Heat and Fluid Flow, 39 (2013) 1–14.CrossRefGoogle Scholar
- A. Sergent, P. Joubert, S. Xin and P. Le Quéré, Resolving the stratification discrepancy of turbulent natural convection in differentially heated air-filled cavities-Part II: End walls effect using large eddy simulation, International Journal of Heat and Fluid Flow, 39 (2013) 15–27.CrossRefGoogle Scholar
- S. Xin, J. Salat, P. Joubert, A. Sergent, F. Penot and P. Le Quéré, Resolving the stratification discrepancy of turbulent natural convection in differentially heated air-filled cavities-Part III: A full convection-conduction-surface radiation coupling, International Journal of Heat and Fluid Flow, 42 (2013) 33–48.CrossRefGoogle Scholar
- R. Puragliesi, Numerical investigation of particle-laden thermally driven turbulent flows in enclosure, Ph.D. Thesis, No. 460, École Polytechnique Fédérale de Lausanne (2010).Google Scholar
- P. Oresta and A. Prosperetti, Effect of particle settling on Rayleigh-Bérnard convection, Physical Review E87 (2013) 063014.Google Scholar
- L. Soucasse, Ph. Rivière and A. Soufiani, Natural convection in a differentially heated cubical cavity under the effects of wall and molecular gas radiation at Rayleigh numbers up to 3x109, International Journal of Heat and Fluid Flow, 61 (2016) 510–530.Google Scholar