Resumen
In this study, a simple and new parametric equation is proposed that describes the relative viscosity of a suspension as a function of suspended solid concentration, covering a range from very dilute to highly concentrated states, based on Costa (2005). The proposed viscosity law depends mainly on the solid volumetric concentration and maximum packing fraction at which a regime transition occurs. Furthermore, the viscosity of dilute as well as a highly-concentrated kaolinite suspension (in excess of 40% and lower than 50%) was measured in a coaxial cylinder rheometer. The proposed formula shows a capability of fitting the measured bulk viscosity into the hyper-concentrated regime in the experiment. Finally, the proposed equation could also be found to show a good fitting relationship with published experimental results on partially crystallised Li2Si2O5 melt and partially melted granite with solid contents from 75% to 95%.