Transport phenomena are processes that redistribute quantities such as mass, momentum and energy. Bulk motion produces advection, while microscopic motion and interactions can produce diffusion, heat conduction and viscosity.
Constitutive laws relate a flux to a driving gradient: Fourier's law gives heat flux , and Fick's first law gives diffusive flux . Combining these relations with conservation balances gives evolution equations. The coefficients and the appropriate transported quantity depend on the medium; a formal similarity between two diffusion equations does not make their physical diffusivities identical.
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Transport phenomena is a field of study that deals with the transfer of mass, momentum, and energy in physical systems. It encompasses the mechanisms and processes that govern how substances move and interact under various conditions. The main areas of transport phenomena include: 1. **Mass Transfer**: This involves the movement of chemical species, such as in diffusion and convection processes.