Dual-Fluid Herschel-Bulkley Model for Pumping Flowable Concrete

Pumping concrete is an important aspect of construction practice. This Demonstration simulates a nonlinear rheological model, known as the Herschel–Bulkley model [1], to obtain analytical predictions of volume flow rate versus pressure loss per unit length . The results are based on the two-fluid Herschel–Bulkley model. We predict the relation between and , given the eight model parameters: three for the rheological properties of the bulk concrete, three for the rheological properties of the fluid in the lubrication layer, pipe radius and thickness of the lubrication layer. In addition to total volume flow rate, the three contributions to the overall volume flow rate are shown: from the LL region, from the shearing-flow region of the bulk concrete and from the plug-flow region of the bulk concrete. The sum of the three contributions is to be compared with observed results for the volumetric flow rate.