Bejan’s heatline analysis of natural convection in right-angled triangular enclosures: Effects of aspect-ratio and thermal boundary conditions
| Autor: | Tanmay Basak, R. Anandalakshmi, Ram Satish Kaluri |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Quantitative features
Materials science Thermodynamics Triangular enclosure Heat flows Isothermal process Triangular cavities Heating Thermal Streamlines streaklines and pathlines Boundary value problem Heat-flow patterns Heatlines Thermal boundary conditions Fluids Thermal mixing Boundary conditions Natural convection Heat flow analysis General Engineering Mechanics Condensed Matter Physics Aspect ratio Nusselt number Flow patterns Isothermal heating Enclosures Heat flux Heat transfer characteristics Heat transfer Linear heating Maximum heat flux Flow measuring instruments |
| Zdroj: | International Journal of Thermal Sciences. 49:1576-1592 |
| ISSN: | 1290-0729 |
| DOI: | 10.1016/j.ijthermalsci.2010.04.022 |
| Popis: | Natural convection in right-angled triangular enclosures with various top angles ( φ =15°, 30°, 45°) is studied in detail via heat flow analysis for various uniform isothermal and linear isothermal heating thermal boundary conditions. Detailed analysis on the effects of aspect-ratio and thermal boundary conditions on the fluid and heat flow inside the triangular enclosures have been carried out for a range of fluids ( Pr = 7.2, 1000, 0.015) within Ra = 10 3 –10 5 . Interesting features of heat flow patterns under various thermal boundary conditions are ‘visualized’ by heatlines. The effect of increase in φ of triangular enclosures is such that the maximum heat flux at the top vertex decreases and the thermal mixing in cavity increases with the increase in φ . It is found that, the fluid in the lower corners is adequately heated in presence of hot right wall compared to that in left wall heating cases. Further, the heat transfer characteristics, in terms of local and average Nusselt numbers, indicate that isothermal heating cases exhibit exponential decrease in Nu l whereas linear heating cases interestingly show local intermediate maxima. Also, various qualitative and quantitative features of Nu and N u ¯ are adequately explained based on heatlines. Finally, the correlations for N u l ¯ and Ra are obtained for various fluid with all heating situations. |
| Databáze: | OpenAIRE |
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