The study of dispersion enables us to understand the rate of dispersion of drugs/nutrients in blood flow, the diffusivity of gases used in Chromatography columns, the dispersion of salt and other materials in estuaries etc. This book contains the mathematical modelling of dispersion of solutes in Herschel Bulkley fluids in circular pipes and annular pipes providing exact solutions to the unsteady convective diffusion equations using the generalized dispersion model. This analysis is applied to blood flows and it should be useful to physiologists, chemical engineers or anyone else who wishes to develop mathematical models to dispersion phenomena in different contexts.