An Analysis of The Entropy Generation in a Square Enclosure
Abstract
:Introduction
Mathematical Formulation
Numerical Solution
Results And Discussion
Conclusion
Nomenclature
g | gravitational acceleration, m/s2 | X, Y | dimensionless coordinates |
H | enclosure height, m | x, y | coordinates, m |
k | thermal conductivity, W/mK | ||
L | enclosure width, m | Greek Letters | |
Ih | heated part, m | α | thermal diffusivity, m2/s |
Ns | dimensionless entropy generation number | β | coefficient of thermal expansion, 1/K |
P | dimensionless pressure | ρ | density, kg/m3 |
p | pressure, N/m2 | θ | dimensionless temperature |
Pr | Prandtl number | ν | kinematic viscosity, m2/s |
entropy generation, W/m3 -K | ζ | dimensionless vorticity | |
Q | overall heat transfer rate, W | ψ | stream function, m2/s |
q | heat flux, W/m2 | Ψ | dimensionless stream function |
Ra | Rayleigh number | τ | dimensionless time |
T | temperature, K | Φ | viscous dissipation function, s-2 |
t | time, s | ω | vorticity, s-1 |
Tavg | average temperature ( =(Th+Tc)/2 ), K | μ | dynamic viscosity, N-s/m2 |
ΔT | temperature difference, K | φ | irreversibility distribution function |
U | dimensionless horizontal velocity component | ||
u | horizontal velocity component, m/s | Subscripts | |
V | dimensionless vertical velocity component | c | cold surface |
v | vertical velocity component, m/s | h | hot surface |
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Pr | Ra | Benchmark values by Lage and Bejan [11] | Grid | Present values at steady-state |
0.01 | 102 | 1.00 | 40 x 40 | 1.004 |
103 | 1.05 | 40 x 40 | 1.080 | |
104 | 1.50 | 40 x 40 | 1.593 | |
105 | 2.77 | 70 x 70 | 2.778 | |
1.0 | 105 | 4.9 | 90 x 90 | 4.674 |
106 | 9.2 | 100 x 100 | 9.194 | |
107 | 17.9 | 100 x 100 | 17.897 | |
108 | 31.8 | 200 x 200 | 31.784 |
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Erbay, L.B.; Altaç, Z.; Sülüs, B. An Analysis of The Entropy Generation in a Square Enclosure. Entropy 2003, 5, 496-505. https://doi.org/10.3390/e5050496
Erbay LB, Altaç Z, Sülüs B. An Analysis of The Entropy Generation in a Square Enclosure. Entropy. 2003; 5(5):496-505. https://doi.org/10.3390/e5050496
Chicago/Turabian StyleErbay, Latife Berrin, Zekeriya Altaç, and Birsen Sülüs. 2003. "An Analysis of The Entropy Generation in a Square Enclosure" Entropy 5, no. 5: 496-505. https://doi.org/10.3390/e5050496