Molecular Diffusivity Estimation (Einstein-Stokes)
Estimation of the molecular diffusion coefficient for a spherical particle in a continuum fluid using the Einstein-Stokes relation.
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1. Define Input Parameters
2. Engineering Output
Absolute Temperature (T_k)
- K
- K
Dynamic Viscosity (SI) (mu_si)
- Pa·s
- Pa·s
Molecular Radius (SI) (R_m)
- m
- m
Molecular Diffusivity (D)
- m²/s
- m²/s
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Molecular diffusivity characterizes the rate at which a solute moves through a solvent due to thermal motion, which is vital for designing mass-transfer operations. The Einstein-Stokes equation offers a reliable first-principles estimation for spherical molecules in dilute solutions. This approach is particularly useful for preliminary equipment sizing and interpreting kinetic data in the absence of experimental measurements.
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