Optical Rheometry of Dense Suspensions

点击翻译按钮获取中文摘要

Birefringence and dichroism refer to variations in the real and imaginary parts of the refractive index with direction for anisotropic media. This research will measure birefringence and dichroism for highly concentrated suspensions in order to gain information on the microstructures than can form when such suspensions are subjected to shear or electric fields. Special emphasis will be placed on measurements as a function of the wave length of light because the strong dependence of dichroism on the ratio of particle size to wave length offers the possibility of probing structures of different length scales in an anisotropic medium. In particular, this may allow characterization of structures in suspensions comprised of particles of different sizes. The research should lead to a more useful tool for characterizing concentrated suspensions under processing conditions. Applications include ceramics casting and electrorheological fluids.