Simulation Analysis of Air Flow and Turbulence Statistics in a Rib Grit Roughened Duct
The implementation of variable artificial roughness patterns on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the ducts of solar air heaters. Different geometries of roughness elements investigated have demonstrated the pivotal role that vortices and assoc...
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| Format: | Article |
| Language: | English |
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Wiley
2014-01-01
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| Series: | The Scientific World Journal |
| Online Access: | http://dx.doi.org/10.1155/2014/791513 |
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| author | I. I. Vogiatzis A. C. Denizopoulou G. K. Ntinas V. P. Fragos |
| author_facet | I. I. Vogiatzis A. C. Denizopoulou G. K. Ntinas V. P. Fragos |
| author_sort | I. I. Vogiatzis |
| collection | DOAJ |
| description | The implementation of variable artificial roughness patterns on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the ducts of solar air heaters. Different geometries of roughness elements investigated have demonstrated the pivotal role that vortices and associated turbulence have on the heat transfer characteristics of solar air heater ducts by increasing the convective heat transfer coefficient. In this paper we investigate the two-dimensional, turbulent, unsteady flow around rectangular ribs of variable aspect ratios by directly solving the transient Navier-Stokes and continuity equations using the finite elements method. Flow characteristics and several aspects of turbulent flow are presented and discussed including velocity components and statistics of turbulence. The results reveal the impact that different rib lengths have on the computed mean quantities and turbulence statistics of the flow. The computed turbulence parameters show a clear tendency to diminish downstream with increasing rib length. Furthermore, the applied numerical method is capable of capturing small-scale flow structures resulting from the direct solution of Navier-Stokes and continuity equations. |
| format | Article |
| id | doaj-art-e30bbddfe9554c7fa5f6d384ea4d30f0 |
| institution | Kabale University |
| issn | 2356-6140 1537-744X |
| language | English |
| publishDate | 2014-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | The Scientific World Journal |
| spelling | doaj-art-e30bbddfe9554c7fa5f6d384ea4d30f02025-02-03T01:31:04ZengWileyThe Scientific World Journal2356-61401537-744X2014-01-01201410.1155/2014/791513791513Simulation Analysis of Air Flow and Turbulence Statistics in a Rib Grit Roughened DuctI. I. Vogiatzis0A. C. Denizopoulou1G. K. Ntinas2V. P. Fragos3Department of Hydraulics, Soil Sciences and Agricultural Engineering, Faculty of Agriculture, Aristotle University of Thessaloniki, 57001 Thessaloniki, GreeceDepartment of Hydraulics, Soil Sciences and Agricultural Engineering, Faculty of Agriculture, Aristotle University of Thessaloniki, 57001 Thessaloniki, GreeceDepartment of Hydraulics, Soil Sciences and Agricultural Engineering, Faculty of Agriculture, Aristotle University of Thessaloniki, 57001 Thessaloniki, GreeceDepartment of Hydraulics, Soil Sciences and Agricultural Engineering, Faculty of Agriculture, Aristotle University of Thessaloniki, 57001 Thessaloniki, GreeceThe implementation of variable artificial roughness patterns on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the ducts of solar air heaters. Different geometries of roughness elements investigated have demonstrated the pivotal role that vortices and associated turbulence have on the heat transfer characteristics of solar air heater ducts by increasing the convective heat transfer coefficient. In this paper we investigate the two-dimensional, turbulent, unsteady flow around rectangular ribs of variable aspect ratios by directly solving the transient Navier-Stokes and continuity equations using the finite elements method. Flow characteristics and several aspects of turbulent flow are presented and discussed including velocity components and statistics of turbulence. The results reveal the impact that different rib lengths have on the computed mean quantities and turbulence statistics of the flow. The computed turbulence parameters show a clear tendency to diminish downstream with increasing rib length. Furthermore, the applied numerical method is capable of capturing small-scale flow structures resulting from the direct solution of Navier-Stokes and continuity equations.http://dx.doi.org/10.1155/2014/791513 |
| spellingShingle | I. I. Vogiatzis A. C. Denizopoulou G. K. Ntinas V. P. Fragos Simulation Analysis of Air Flow and Turbulence Statistics in a Rib Grit Roughened Duct The Scientific World Journal |
| title | Simulation Analysis of Air Flow and Turbulence Statistics in a Rib Grit Roughened Duct |
| title_full | Simulation Analysis of Air Flow and Turbulence Statistics in a Rib Grit Roughened Duct |
| title_fullStr | Simulation Analysis of Air Flow and Turbulence Statistics in a Rib Grit Roughened Duct |
| title_full_unstemmed | Simulation Analysis of Air Flow and Turbulence Statistics in a Rib Grit Roughened Duct |
| title_short | Simulation Analysis of Air Flow and Turbulence Statistics in a Rib Grit Roughened Duct |
| title_sort | simulation analysis of air flow and turbulence statistics in a rib grit roughened duct |
| url | http://dx.doi.org/10.1155/2014/791513 |
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