Vibrational Effect on Entropy Generation in a Square Porous Cavity
Abstract
:Introduction
Equations and Numerical Methods
Entropy Generation
Nuav | |||
---|---|---|---|
Ra=10 | Ra=100 | Ra=1000 | |
Baytas and Pop [10] | 1.079 | 3.16 | 14.06 |
Walker and Homsy [11] | -------- | 3.10 | 12.96 |
Gross et al. [12] | -------- | 3.14 | 13.45 |
Manole and Lage [13] | -------- | 3.12 | 13.64 |
Moya et al. [14] | 1.065 | 2.80 | ------- |
Present prediction | 1.079 | 3.14 | 13.82 |
Results and discussion
Conclusions
Nomenclature
A | Area of the cavity, m2. |
Be | Bejan number, (see Eq. (8)). |
Cp | Specific heat of the fluid, J.kg-1.0C-1. |
Cs | Specific heat of the solid matrix, J.kg-1.0C-1. |
Ecm | Modified Eckert number = . |
K | Permeability of the porous media, m2. |
KE | Kinetic energy, J. |
Ns | Entropy generation number, (see Eq. (7)). |
Nu | Nusselt number, (see Eq. (9)). |
Pr | Prandtl number = ν/α. |
Ra | Rayleigh number, (see Eq. (3)). |
Entropy generation rate, W.m-3.K-1. | |
Characteristics entropy transfer rate, (see Eq. (5)). | |
T | Temperature of the fluid, 0C. |
T0 | Reference temperature, 0C. |
t | Time, sec. |
u* | x-component of the velocity, m.sec-1. |
v* | y-component of the velocity, m.sec-1. |
u | x-component of the dimensionless velocity = u*/u0. |
v | y-component of the dimensionless velocity = v*/u0. |
u0 | Reference velocity = α/W. |
W | Width and height of the cavity, m. |
x* | Horizontal distance, m. |
y* | Vertical distance, m. |
x | Dimensionless horizontal distance =x*/W. |
y | Dimensionless vertical distance =y*/W. |
Greek symbols | |
α | Thermal diffusivity of the fluid, m2.sec-1. |
β | Thermal expansion coefficient of the fluid, 0C-1. |
ψ* | Streamfunction, m2.sec-1. |
ψ | Dimensionless streamfunction = ψ*/α. |
Θ | Dimensionless temperature = (T-T0)/ΔT. |
ω* | Angular frequency, Hz. |
ω | Dimensionless angular frequency, (see Eq. (3)). |
ρ | Density of the fluid, kg.m-3 |
ρs | Density of the solid matrix, kg.m-3 |
τ | Dimensionless time = t.α/(W2.σ). |
σ | Empirical constant (see Eq. (3)) |
ν | Kinematic viscosity of the fluid, m2.sec-1. |
∀ | Volume of the cavity, m3. |
ϕ | Porosity of the porous media. |
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Mahmud, S.; Fraser, R.A. Vibrational Effect on Entropy Generation in a Square Porous Cavity. Entropy 2003, 5, 366-376. https://doi.org/10.3390/e5050366
Mahmud S, Fraser RA. Vibrational Effect on Entropy Generation in a Square Porous Cavity. Entropy. 2003; 5(5):366-376. https://doi.org/10.3390/e5050366
Chicago/Turabian StyleMahmud, Shohel, and Roydon Andrew Fraser. 2003. "Vibrational Effect on Entropy Generation in a Square Porous Cavity" Entropy 5, no. 5: 366-376. https://doi.org/10.3390/e5050366