A penetroviscosimeter for Newtonian and visco-plastic fluids

The penetration test has been widely used by engineers to characterize the behavior of materials such as soils, fresh concrete, or concentrated suspen sions. These approaches provide related measurements to rheological propert ies by means of empirical parameters. The present paper, based on Bikerman' s works,(1) describes an analytical method for a penetration test, for Newt onian or Binghamian fluids. Characteristics of the flow between the bowl and the plunger are determined using an end effect correction method. In the case of Newtonian fluids, th e theoretical developments are validated by experiments on a standard mater ial. The material density is also determined using the same measurements. For the Bingham behavior, the total set of equations is presented. The limi ting cases of low and infinite velocity are studied and applied to a very c oncentrated suspension. The viscosity and the yield stress are compared to the results of capillary and vane shear experiments. The same order of magn itude is found. However, we show here that these properties are only equiva lent ones for this material, due to the slip motion observed at the penetro meter walls.