Center of Engineering and Multiscale modeling of Fluid flow
Discrete element method (DEM) is an Lagrangian method for simulating granular flow and multiphase flow containing solid particles. Particles can be spherical or non-spherical with irregular shape.
In Discrete Element Method (DEM), particles may be considered as either deformable or rigid, which continuously come into contact with each other and rebound. The translational and rotational motions of each body are formulated in the model and are highly dependent on type and strength of interactions of the bodies with the surrounding medium through contact and interparticle effects.
The particles may interact with each other through their contact points/areas. Depending on the operating conditions of the system, interparticle interactions, such as van der Waals, liquid bridge, and electrostatic forces, may exist between distinct bodies even if they are not in contact. In multiphase flows, the fluid interacts with the distinct bodies in the system. The interaction between each body and the fluid is mutual. During the motion of bodies, they interact with stationary or moving walls. Moving walls increases the kinetic energy of bodies leading to convective movement.
We investigate mixing mechanism in a rotating drum operating in rolling regime. To this end, a drum with the diameter of 0.2 m and depth of 0.03 m is half-filled with 19000 3-mm spherical particles. Rotation speed of the drum is 10 RPM. This rotation speed creates the cascading regime…
In this DEM simulation, we create a random packed bed of spherical particles in a cylindrical container with the diameter of 15 cm and height of 20 cm. Particles are a mixture of spherical particles with similar density (2500 kg/m3) and uniform sizes distribution between 3 and 7.5 mm. In…
In this simulation, we create a random packed bed of particles (packed bed of spheres) in a cylindrical container with the diameter of 15 cm and length of 20 cm. To create this bed, 8000 7-mm spherical particles with the density of 2500 kg/m3 are used. In the followings, we…
In many occasion in process industries (i.e. chemical engineering), we need to create a random packed bed of Catalysts. Packing of Hollow Cylinders in reactor (heterogeneous catalytic reaction) tubes can be simulated using DEM. This packing will then be used in other reactor flow simulations for more detailed kinetics, heat…
Many industrial processes like granulation, particle coating, bio-mass pyrolysis, dryers contain rotating drum as a part of their processes. its rotation cause a gentle motion of particles. So, this gentle motion brings particle to the bed surface, where particles avalanche from top to bottom. The drum wall pulls particles up…
Screw conveyor uses the power of a rotating helical ribbon to transport solids from one place to another. They usually are horizontal or with a slight angle with respect to horizon. They have applications in many industries including chemical and petrochemical, power plants, cements, paper, flour, iron and steel foundries,…
V-blender (V-mixer) is found in most of solid processing industries. They provide reliable and easy mixing of dry powders in batch mode. This mixer can be found in many industries such as food and pharmaceutical processing. You see a list of V-blender applications here: Food processing : mixing of dairy…