EXPERIMENTS ON FREE-SURFACE PHENOMENA

This paper reviews an experimental program in which predictions from domain perturbation theory for motions which perturb the rest state are used in conjunction with experimental measurements on free surface deformations associated with the Weissenberg effect at low rates of shear to obtain values for certain rheological parameter. The experiments include free surface measurements on a liquid near a circular rod rotating in steady motion and oscillatory motion in a large volume of fluid, secondary flows and circumferential velocity measurements in steady rod climbing, normal stress amplification effects, and free surface shapes on a fluid confined between rotating cylinders. Temperature effects are noted, and interesting instability phenomena at high rates of shearing are demonstrated. © 1979.