Gravity Segregation of Miscible Fluids in Linear Models

Abstract

Some cases of the motion of two miscible fluids in uniform linear models are discussed. There is no bulk flow through the models, and the convection currents are caused solely by density gradients. Horizontal, vertical and inclined positions of the models are treated separately. Analytical formulas for the motion of a narrow transition zone between the fluids are obtained and compared with measurements , and the limitations are discussed. Observations of the ultimate stabilizing effect of diffusion on the motion are compared with the theory. It is shown that fluid motion in an inclined model with a constant rate of bulk flow can be directly deduced from the cases disc.ussed, provided the v'iscosity ratio is small.