The behaviour of a Bingham fluid in the cone-and-plate viscometer

A theoretical explanation of the shear-stress characteristics of a Bingham fluid as given by a cone-and-plate viscometer is developed for the case when the fluid is separated from the surfaces of the instrument by a thin layer of Newtonian liquid. It is shown to apply qualitatively to china clay suspensions and a method of deriving the true parameters of the fluid from the flow curve is given.