Physics

Eigenfunction

Perturbation (astronomy)

Mathematics

Mechanics

Diffusion

Optics

Taylor dispersion

Asymptotic expansion

Gaussian

Mathematical analysis

Eigenvalues and eigenvectors

Dispersion (optics)

Quantum mechanics

Classical mechanics

Thermodynamics

Physical Review Fluids

We consider a setting with two infinite parallel plates, where the diffusive substance is adsorbed at the lower plate, simultaneously advected longitudinally by a main flow and vertically by a crossflow. We utilize the classical method of moments along with the eigenfunction expansion to calculate the moments up to fourth-order, and thus the effects of non-Gaussian properties can be reflected. Compared with the result of Brownian dynamics simulations, the present work is shown sufficient to cover the pre-asymptotic dispersion regime out of reach of the generalized Taylor dispersion (GTD) method and dual-perturbation method.

Transient dispersion in a channel with crossflow and wall adsorption