The core theory establishes that transport phenomena for mass, momentum, and energy share a unified physical basis governed by three specific diffusivities: molecular diffusion coefficient ($D$), thermal diffusivity ($\alpha = k/\rho c_p$), and kinematic viscosity (momentum diffusivity). The fundamental governing mechanism is the ratio of convective transport to diffusive transport, which defines dimensionless numbers such as the Reynolds number ($Pe_m = UL/\nu$, $Re^*$) and Prandtl/Schmidt numbers. This framework dictates that non-dimensional fluxes, traditionally expressed via Nusselt or Sherwood analogies, are functions of ratios between inertial-convective forces and viscous-diffusive forces within the domain of transport physics.
The core theory establishes that transport phenomena for mass, momentum, and energy share a unified physical basis governed by three specific diffusivities: molecular diffusion coefficient ($D$), the…