The Reynolds number (Re) is a dimensionless quantity that represents the ratio of inertial forces to viscous forces in a fluid flow.
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- Re is the Reynolds number,
- Ļā is the density of the freestream fluid,
- Vā is the velocity of the freestream fluid relative to the object (freestream velocity),
- c is a characteristic length of the object (e.g., chord length for an airfoil),
- Ī¼ā is the dynamic viscosity of the freestream fluid.