As you know, Conveyor Dynamics, Inc. (CDI) and others have been using DEM, since 1995 in the design of conveyor chutes, gyratory, cone, roll, and impact crushers, AG, SAG, ball, rod, and vertical mills, and many other forms of comminution systems.

Vibrating screens and other classifiers have been improved through DEM application.

We use DEM to simulate flow in bins, bunkers, stockpiles and other containment systems.

In addition, DEM is used to simulate blasting, block caving and other forms of mine operation.

CDI has designed hundreds of chute systems in coal, iron ore, limestone, bauxite, copper ore and concentrate, and many other mineral groups.

Multiphase flow of rock, fluid and gas have been performed.

Present studies include incorportion of Molecular Dynamics to study nano-particle polishing of computer chips.

Breakage of particles has been in use since 1998 to advance the science of comminution and degradation .

Wear mechanics of SAG mill lifter designs has been extremely successful. THis has lead to significant improvements of liner life and mill output per kW.

Belt and chute liner wear have produced great increases in life expectancy of belts and liners.

Product degradation and dust production have some great improvements.

CDI has 10-20 CPU's operating on designs every day 24 x 7.

Why the question? ■

A cautionary note:

Not all DEM codes produce the same result. How do you know if the code is replicating the real world. Does it create or destroy mass or energy. Some codes do not preserve the kinetic energy transfers. There are some good tests to assure compliance with the physical world.

Does the particle configuration represent realistic events with appropriate physics. Can the code replicate J&J or other shear cell test yield loci stress curves?

Does the particle shape replicate the shear work and impact action.

What about particle size distribution. Can the code handle 10:1 or 20:1 particle size (diameter passing) range? Can the code handle sufficient particle size count > 10^6 if required? Can realistic geometries be handled?

What about moisture and the liquid brigde effect with finer particles? What about Einstonian and Van der Waal forces in fine particles?

Do you have elastic, viscoelastic or viscoplastic interactions?

The list of what should be known is extensive. It is a list you should know before making decisions. ■

Love to hear from you and wishing Happy Holidays and Best Success in the New Year. ■

Glenn,

Glad you could visit us at www.ChuteMaven.com. There are several applications that DEM is very successful at modeling. Please contact us for further questions.

Best Regards,

Ginger

Hustrulid Technologies Incorporated

1-305-433-4891

Support@ChuteMaven.com ■