Horizontal Drum Mixer Research Articles

Simulation Modeling of Non-Homogeneous Mixture in the Horizontal Drum Mixer

The paper proposes a simulation model of the diffusion mixing of solids, based on the theory of probability and stochastic diffusion model of imperfect processes of solid particles. It is assumed that the particles have different sizes and density. Model of the program implemented in the AnyLogic SoftWare. Developed a simulation model to evaluate the differences between the intense mixing processes in time and assess their impact on the course of other processes in a horizontal drum mixer.

Optimization of Parameters Dry Construction Mixtures in the Horizontal Drum Mixer

In the article the process of continuous mixing of dry construction mixtures and developed an experimental mathematical model of horizontal drum mixer. It is noted that the qualitative analysis of the structure of the mixing process should take into account semantic and mathematical description of the mixing process of building materials in the horizontal continuous mixer drum. On the basis of the developed mathematical model simulation work performed horizontal drum mixer software environment AnyLogic.

Optimization of process parameters mixing dry construction mixtures in the horizontal drum mixer continuous simulation method

In the article the process of continuous mixing of dry construction mixtures and developed an experimental mathematical model of horizontal drum mixer. It is noted that the qualitative analysis of the structure of the mixing process should take into account semantic and mathematical description of the mixing process of building materials in the horizontal continuous mixer drum. On the basis of the developed mathematical model simulation work performed horizontal drum mixer software environment AnyLogic.

A design heuristic for optimizing segregation avoidance practices in horizontal drum mixers

Segregation is a major problem for many solid processing industries. Differences in particle size or density lead to flow-induced segregation within the surface layer. Here we examine methods of avoiding radial segregation in a horizontal drum mixer. Recently, it has been suggested that segregation in this type of particle mixer can be thwarted if the sheared (surface) regions of the bed are inverted at a rate above some critical frequency. Further, it has been hypothesized that the effectiveness of this technique can be linked to the probability distribution of the number of surface layer “passes” a particle takes per rotation of the drum. In this article, various baffle configurations are numerically and experimentally studied to investigate the efficacy of this measure as a design heuristic for the development of improved drum mixing devices. We choose the horizontal drum geometry as it represents the simplest possible example of a tumbler-type mixer, however, we expect the results found here regarding the efficacy of our design heuristic to be generic for any surface-dominated mixing device.

Stochastic Modelling of Particle Segregation in a Horizontal Drum Mixer

A process of segregation of two distinct fractions of solid particles in a rotating horizontal drum mixer was described by stochastic model assuming the segregation to be a diffusion process with varying diffusion coefficient. The model is based on description of motion of particles inside the mixer by means of a stochastic differential equation. Results of stochastic modelling were compared to the solution of the corresponding Kolmogorov equation and to results of earlier carried out experiments.

Description of segregation in a horizontal drum mixer by use of the diffusion equation

An attempt has been made to describe the axial segregation of solid particles of two dimensions in a horizontal drum mixer. For this purpose the Kolmogorov's forward diffusion equation with variable diffusion coefficient and zero drift velocity was used. For the case of "pure" segregation this approach has given good results.

Stochastic diffusion model of non-ideal mixing in a horizontal drum mixer

Since a non-ideal solid particle system contains particles of different sizes and/or densities, mixing of non-ideal particle systems in a horizontal drum mixer is complex and stochastic in nature. In the present work such non-ideal mixing process has been modeled by the Kolmogorov diffusion equation. Two parameters appearing in the Kolmogorov diffusion equation, the diffusion coefficient and drift velocity, have been determined in this work from one-step tracer experiments, and their physical significances have been discussed. The convective or drift velocity, which varies with respect to the axial position of the mixer, appears to be important in illucidating the non-ideal mixing characteristics. A good agreement between the model and the experimental data has been observed.

Motion and Segregation of Solid Particles of Different Density in a Horizontal Drum Mixer

Motion and Segregation of Solid Particles of Different Density in a Horizontal Drum Mixer

Segregation of Solid Particles in a Horizontal Drum Mixer

Segregation of Solid Particles in a Horizontal Drum Mixer

A probabilistic model of the diffusional mixing of particulate solids

Three probability distributions governing particle movement within a horizontal drum mixer have been defined. For a mixer which has been conceptually divided into sections of equal width, by passing planes through the mixer perpendicular to its axis, a relationship for the diffusion coefficient based on these probability distributions has been derived from Fick's First Law. Observations of the movement of an individual particle were used as a direct means of evaluating the Fick's First Law diffusion coefficients for various combinations of mixer load and speed. A second set of diffusion coefficients was obtained from observations of actual mixing. A linear regression between the two sets of diffusion coefficients showed that they are highly correlated. It was found that the frequency of collisions resulting in particle movement is affected by an interaction between the mixer speed and load and that the average distance which a particle travels is affected by the mixer load, but not by the mixer speed.