The two main purposes of this tutorial are to learn how to define the mantle and shaft movements required for a Cone Crusher simulation, and how to set up Tavares breakage model parameters.

You will learn how to:

And you will use these features:

The geometries in this tutorial are composed of:

The .stl files can be found in the tutorial directory.

To get started with this tutorial, do the following:

For this tutorial, information about Power on the boundary will be used.

Therefore, we must enable the collection of Boundary Collision Statistics during the Modules step.

For the Geometries step, we will import the following six separate geometry files in .stl format, disable the Feed Hopper geometry during initial particle release, and then add a surface (to associate with an inlet) to release particles into the domain.

In this tutorial, we will be creating cone crusher movements, which are defined by the following motions:

These motions can be created in Rocky with a special Cone Crusher Frame that is added during the Motion Frames step.

When the new Cone Crusher Frame is added to your project, the following options are available in the Data Editors panel:

In addition, the Cone Crusher Frame will automatically create two separate motions that are designed to be applied to the appropriate geometries.

These two motions include the following:

How to calculate Initial Orientation:

For the Motion Frames step, we will add a type of motion frame that is specific to the cone crusher:

The frame's two components can now be assigned to their respective geometries.

At this point, the movement can be previewed.

For the Materials step, two materials will be used:

For the Particles step, we will create a new (rock-like) polyhedron-shaped particle group, in a range of sizes, with random orientation, and with the Tavares breakage model enabled.

For this tutorial, we will change the orientation of the particles as they are injected into the inlet.

To set the orientation of the particle:

For this tutorial, we will enable the Tavares breakage model.

Like Ab-T10, the Tavares model is based upon the Voronoi fracture particle subdivision algorithm.

However, the breakage energy probability and resulting fragment size distribution are based upon the Tavares et al. (UFRJ) approach, which:

To set the Breakage Model:

For the Inlets and Outlets step, we will create a Particle Inlet and then set our Circular Surface as the location from which we want particles to enter the simulation.

For the Solver step, we will also define our breakage start and delay times.

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

The Simulation Summary screen appears (as shown), then processing begins.

This completes Part A of this tutorial, in which Rocky was used to set up and process a cone crusher simulation.

During this tutorial, it was possible to:

What's Next?

The main purpose of this tutorial is to learn how to analyze the results from the Cone Crusher simulation that we set up and processed in Part A.

You will learn how to:

And you will use these features:

Once processing is complete, you can analyze the resulting Particle Size Distribution (PSD) of the fragments.

We will do this by:

In the last Timestep of the simulation, you can observe that some Particles are accumulating in an open space of the transmission housing (in the Blue cube) (as shown).

Using the Divisions Tagging Calculation of the Particles in the hopper, we can identify from what section of the hopper these particles are coming from, which is helpful information for improving the equipment design.

For this case, we will create a Cylinder User Process at an Output Time far enough into the simulation that the Hopper is full of particles.

Color Particles using the newly added Property:

You should now see all of the following:

Lastly for this analysis, a Cube will be added to separate the accumulated Fragments from the rest of the Particles.

Then, another Histogram will be created to show the hopper region from which the accumulated Fragments are originating.

From the Histogram, it can be seen that most of the accumulated Fragments are coming from bins 1 and 12 of the hopper.

This information may not have been obvious before the Divisions Tagging analysis. Now, an appropriate solution can be devised if this particular result is undesirable.

It might also be useful to filter out the particles that actually broke; in Rocky, these broken particles are called fragments.

One way to isolate these fragments is by using the Laguerre-Vonoroi Size property, which has the following characteristics:

Using this property, the particles that did not break will have values equal to zero.

Therefore, to filter out only the fragments, we will select only the particles that have a Laguerre-Vonoroi Size value greater than zero.

Let's start by creating the Filter User Process.

Then, to visualize in a 3D View window only the filtered fragments:

The view now shows only the particles that have broken (fragments).

Earlier in Part A, we turned on the collection of some Boundary Collision Statistics; specifically, those regarding Intensities.

We can now use the resulting data to estimate how much power is required by the equipment, which is commonly known as Power Draw.

The Average Power Draw of the geometries can be estimated by the following expression:

(8–2)

where:

First, let's define .

The plot shows the operation conditions start after 2.5 seconds (in which the breakage starts), so = 2.5s.

Now, let's apply the Average Power Draw formula to the Power curve.

The new Average Power (Custom) curve appears on the Curves tab for the selected geometry, but is also made available for all other geometries automatically.

Now, let's sum the Average Power of the Mantle Cone and the Mantle Shaft geometries to estimate the Average Power Draw of the equipment:

Each row of this table shows the average power measured from 2.5s to the time shown in Column A.

Thus, the Average Power Draw of the simulation is in the last row of this table and it is 4840.28 W (as shown).

This completes Part B of this tutorial, in which Rocky was used to analyze the results from a cone crusher simulation.

During this tutorial, it was possible to:

What's Next?