Large Eddy Simulation of Liquid Metal Turbulent Mixed Convection in a Vertical Concentric AnnulusSource: Journal of Heat Transfer:;2018:;volume( 140 ):;issue: 007::page 72504DOI: 10.1115/1.4038858Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: In the present study, turbulent forced and mixed convection heat transfer to a liquid metal flowing upwards in a concentric annulus is numerically investigated by means of large eddy simulation (LES). The inner-to-outer radius ratio is 0.5. The Reynolds number based on bulk velocity and hydraulic diameter is 8900, while the Prandtl number is set to a value of 0.026. A uniform and equal heat flux is applied on both walls. LES has been chosen to provide sufficiently accurate results for validating Reynolds-averaged turbulence models. Moreover, with the thermal sublayer thickness of liquid metals being much larger than the viscous hydrodynamic one, liquid metals present a separation between the turbulent thermal and hydrodynamic scales. Thus, with the same grid resolution, it is possible to perform a LES for the flow field and a “thermal” direct numerical simulation (DNS) for the temperature field. Comparison of the forced convection results with available DNS simulations shows satisfying agreement. Results for mixed convection are analyzed and the differences with respect to forced convection at the same Reynolds number are thoroughly discussed. Moreover, where possible, a comparison with air is made.
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| contributor author | Marocco, Luca | |
| contributor author | Garita, Francesco | |
| date accessioned | 2019-02-28T11:01:14Z | |
| date available | 2019-02-28T11:01:14Z | |
| date copyright | 4/6/2018 12:00:00 AM | |
| date issued | 2018 | |
| identifier issn | 0022-1481 | |
| identifier other | ht_140_07_072504.pdf | |
| identifier uri | http://yetl.yabesh.ir/yetl1/handle/yetl/4251796 | |
| description abstract | In the present study, turbulent forced and mixed convection heat transfer to a liquid metal flowing upwards in a concentric annulus is numerically investigated by means of large eddy simulation (LES). The inner-to-outer radius ratio is 0.5. The Reynolds number based on bulk velocity and hydraulic diameter is 8900, while the Prandtl number is set to a value of 0.026. A uniform and equal heat flux is applied on both walls. LES has been chosen to provide sufficiently accurate results for validating Reynolds-averaged turbulence models. Moreover, with the thermal sublayer thickness of liquid metals being much larger than the viscous hydrodynamic one, liquid metals present a separation between the turbulent thermal and hydrodynamic scales. Thus, with the same grid resolution, it is possible to perform a LES for the flow field and a “thermal” direct numerical simulation (DNS) for the temperature field. Comparison of the forced convection results with available DNS simulations shows satisfying agreement. Results for mixed convection are analyzed and the differences with respect to forced convection at the same Reynolds number are thoroughly discussed. Moreover, where possible, a comparison with air is made. | |
| publisher | The American Society of Mechanical Engineers (ASME) | |
| title | Large Eddy Simulation of Liquid Metal Turbulent Mixed Convection in a Vertical Concentric Annulus | |
| type | Journal Paper | |
| journal volume | 140 | |
| journal issue | 7 | |
| journal title | Journal of Heat Transfer | |
| identifier doi | 10.1115/1.4038858 | |
| journal fristpage | 72504 | |
| journal lastpage | 072504-10 | |
| tree | Journal of Heat Transfer:;2018:;volume( 140 ):;issue: 007 | |
| contenttype | Fulltext |