Vadasz number, abbreviated as Va, a dimensionless number, governs the effect of porosity on flow in a porous media. It characterizes the relative importance of buoyancy driven flow to viscous forces in a rotating system. The Vadász number is particularly useful in analyzing convective heat transfer and fluid flow in systems influenced by rotation, such as geophysical flows, rotating machinery, or convection in porous rotating layers.
Key Points about Vadász Number
- When the Vadász number is "high", buoyancy effects dominate over rotational effects in the fluid flow.
- When the Vadász number is "low", rotational effects play a more significant role compared to buoyancy forces.
Vadasz Number formula |
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\( Va \;=\; \dfrac{ \phi \cdot Pr }{ Da }\) (Vadasz Number) \( \phi \;=\; \dfrac{ Va \cdot Da }{ Pr }\) \( Pr \;=\; \dfrac{ Va \cdot Da }{ \phi }\) \( Da \;=\; \dfrac{ \phi \cdot Pr }{ Va }\) |
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| Symbol | English | Metric |
| \( Va \) = Vadasz Number | \( dimensionless \) | \( dimensionless \) |
| \( \phi \) (Greek symbol phi) = Porous Media | \( dimensionless \) | \( dimensionless \) |
| \( Pr \) = Prandtl Number | \( dimensionless \) | \( dimensionless \) |
| \( Da \) = Darcy Friction Factor | \( dimensionless \) | \( dimensionless \) |
