Observations of shear-augmented diffusion processes and evaluation of effective diffusivity from current measurements in Corpus Christi Bay

摘要

Studies on the process of diffusion in fluids have shown that in the presence of a shear structure within the current field, the observed spreading of a marked fluid can be augmented significantly. Shear-diffusion becomes the dominant diffusion process after a time T-n, the initialization time has elapsed. Given the existence of a vertical shear structure within the flow field, the characteristic vertical mixing time, T-c having an inverse relation to vertical turbulent diffusivity, K-z governs this initialization time.