Predicting the capacity of an off-road self-loading drum mixer with different concrete consistencies through three-dimensional fluid dynamics analysis

The design features of machinery for concrete production are closely connected with the maximum volume capacity of processed material. Regarding the design of off-road concrete mixer trucks, there are many key parameters that define the final capacity, for example the geometric dimensions, the rotational speed and the concrete consistency. This paper presents a numerical investigation of an Eulerian-Eulerian multiphase CFD model applied to an off-road self-loading concrete truck mixer, which simulates the maximum concrete capacity by varying the concrete consistency. The calibration is performed by matching the maximum capacity of a commercially available drum, under different concrete consistency classes, with the yield stress value of the non-Newtonian Bingham model applied to the rheological properties of the simulated fresh concrete. This model can be used for the design of new concrete mixers, in order to predict the maximum capacity of the drum under different conditions and geometric design aspects. This work intends to highlight the calibration method and the numerical Bingham values applied to fresh concrete, in order to quantify concrete drum capacity while changing the fresh concrete consistency.