The main purpose of this tutorial is to set up and process a High Pressure Grinding Roll (HPGR) simulation, with the goal of later (in Part B) analyzing both power and wear data on the boundaries.

You will learn how to:

And you will use these features:

The geometries in this tutorial are composed of:

For all but the first item, which will come from a conveyor template within Rocky, the .stl files can be found in the tutorial directory.

To begin the steps for this tutorial, do the following:

For the Modules step, we will be turning on the collection of some Boundary Collision Statistics so that we may later analyze Intensities information, such as power and shear.

Besides importing the HPGR components, a Feed Conveyor will be added to this tutorial, which will come from a Conveyor Template included by default within Rocky.

Rocky not only allows Custom geometry import but also provides some default geometries that you can add to your projects and then customize.

The Feed Conveyor can input the particles if you associate an inlet to it, so you don't need a separate surface.

For the Motion Frames step, we will create three separate Motion Frames: one each for the HPGR rolls, and one for the deflector plate.

When the motion Type of Spring-Dashpot Moment (or Spring-Dashpot Force) is selected, you must then prescribe the direction and the coefficients of the Spring/Dashpot.

The moment (M) and force (F) components at the selected direction for this motion will be proportional to the displacement (Spring) and velocity (Dashpot) of the geometry, compared to the original position.

(6–1)

(6–2)

Where:

Since the Deflector has a free body motion, it is important to correctly define the Boundary Mass, Gravity Center and Moment of Inertia properties.

In addition, the Surface Wear Modification model will be enabled for the Deflector.

Next, we will define the interactions between materials.

For the Particles step, we will create a new (rock-like) polyhedron-shaped particle group in a range of sizes, and will define for it Ab-T10 breakage parameters.

Lastly, we will define an inlet and solver information for this project.

With a 3D View opened, your Data and Workspace should look similar to the image below.

The Simulation Summary window will be displayed, and then processing begins.

This completes Part A of this tutorial.

Rocky was used to set up and process an HPGR simulation with the goal of later analyzing both power and wear data on the boundaries.

During this tutorial, it was possible to:

What's Next?

The main purposes of this tutorial are to analyze the particle fragments, view the surface wear modifications, and compare the power data that we collected in the High Pressure Grinding Roll (HPGR) simulation we processed in Part A.

You will learn how to:

And you will use these features:

Because in Part A, we enabled the Ab-T10 Breakage Model on our particles, we are now able to analyze those breakage results.

As particles pass through the rolls of the HPGR, they break into fragments.

By creating a Cube User Process under the rolls, we can collect these fragments and then analyze them by size.

The final Histogram shows the cumulative particle (and fragment) size after the original particles go through the rolls.

Note that more than 50% of the particle mass accounted for within the Cube is of a smaller particle size ([0.13, 0.15] (m)) than the smallest particle originally injected (0.15 m).

Because in Part A we enabled the Surface Wear Modification model for the Deflector wall, we are now able to evaluate the results.

Modifications to the geometry can be viewed using the Filter User Process, and then defining Displacement as the Property to analyze. This will show the distance each node was moved.

The results should show only the triangles of the deflector surface that had displacements within the selected displacement range (as shown).

The worn area on the surface of the Deflector geometry can be evaluated using a Time Plot of the Filter <01> User Process you just created.

The resulting plot should look similar to the one below.

After analyzing the Displacement and Displacement Area, you were able to visualize the affected area on the Geometry Surface and plot this.

Another possible analysis is to verify the Wear Volume Loss that the Geometry suffered. Follow the steps below to visualize the Deflector Geometry's volume loss due to wear and create a Time Plot of the Wear Volume Loss property.

You can also analyze wear on the geometries without modifying the surface.

You might recall that in Part A we enabled the Module for Boundary Collision Statistics, and chose to collect Intensities.

Now that we have that data, we can use it to create a color map of the intensities data, such as shear.

The color map should look similar to the image below.

It takes a certain amount of power for the two Roll geometries to successfully comminute the material.

We can use the same Intensities data we chose to collect in Part A to measure the power draw directly from the geometries.

The results should look similar to the plot below.

This is a useful way to compare the results with real data and to calibrate the material properties correctly.

This completes Part B of this tutorial.

Rocky was used to study breakage, surface wear, and power draw in an HPGR.

During this tutorial, it was possible to:

What's Next?