Stacker Mesh Workflow: Hexahedral Mesh for IC, Package, and PCB

Stacker Mesh Workflow. Hexahedral mesh for IC, package, and PCB. Hi everybody, this is Edwin Rodriguez from Ozen Engineering Inc. and today we are going to use the Stacker Mesh workflow to easily create a mesh in geometries like the printed circuit board assemblies.

We can see here the concept of stacker.

Having this complex geometry, we are going to project all the bodies in a base phase, and we can see all the profiles here, and then we can create a quadrilateral mesh on that phase, meaning we are going to mesh only in two dimensions, and then we can stack up to create a hexahedral mesh.

Let's move to the software to see how it works. We have here this PCB assembly geometry where we can identify some PCBs, some chips represented by blocks, and these solder joints which are not blocks, they are like curvy geometries that represent the ball joints.

We can see also that our geometry has shared topology created from Discovery. Now we can go to mesh and add our workflow from mesh workflows, Stacker Mesh workflow. We can see that there are three main tasks that will be performed to create the mesh.

The input will transfer the geometry to the mesh workflow, the steps will create the mesh, Finally, the output will deliver the mesh to the model. Now we can follow the input. In the input we are going to select our multibody part. We can say Ctrl A with the keyboard and apply.

Now I have one part here. And I can run this task. I can do it in two ways. By right click, in this case initialize workflow, or I can use this button from the control or you can also use the When I move to the Domain Browser, I can see there is the Part, which is the Multibody Part.

and I can still see the individual volumes representing all the geometry. OK, we can move to the next steps, where we can identify 9 different steps to create the Stacker Mesh from this model. The first task will be the merge parts.

Inside each step we can see we have the controls, which is this part where we can define and control the task, and we have the outcome, which is the result of the operations. In this case we don't need to define anything, just running the task.

Then the second task will be identifying the stackable bodies In this case we expect to identify all the block geometries as stackable bodies because it is similar to swept meshing and all the solder ball joints to be non-stackable bodies. And we can perform the operations.

In the control, we can see we have the scope for this task is the outcome from the previous operation, which is the merged parts outcome. and then we can execute this task. Now we have two groups.

First one, in the blue, is the stackable bodies, as we expected, it's all the block parts, and the non-stackable bodies scope is the orange highlighted here for the solder ball joints. Okay, we can also see from the steps we have some definitions which are important for our mesh workflow.

We can see we have global settings that identifies the mesh sizing that will be performed here, and we have the stacker settings. In this case, by these properties, we are defining the base phase where the 2D mesh will be created.

We can see this is located in the origin of the global coordinate system and the vector definition, which is done by these three directions, is pointing through the Z axis. Okay, continuing with our workflow, we can move to the next task that is the multi-zone.

In this task, we want all the parts which have been identified as non-stackable to be meshed. We can see the outcome of this, the scope for this task is the outcome from the previous task which is the non-stackable bodies scope, meaning the nine solder joints.

And then we can see some settings which are the values we are going to use to mesh those bodies. If I execute this task, I can see there is an error, meaning the mesh was not successful. and this is because the size of the mesh is too high for this geometry.

I can go back by revert to step and modify this mesh sizing. Instead of using settings, I am going to use value and I can type more adequate size values for the element size and the sweep direction size.

and that way I can execute my task again and see how the mesh is generated in this specific bodies. And we can see this is a beautiful mesh for this core bodies.

We can continue for the next step which is the diagnostics In this case we want to identify dimensions in the lateral that will be the plane in this case xy directions and in the vertical minimum sizes in order to create our 3D mesh I am going to just execute the step and I can see how these values are detected through the task to create the subsequent mesh.

In the next step, the 5th, we are going to create that surface and we are going to project all the bodies into that base phase. And this task is called Flatten Value. We can see the scope for this task is the previous outcome, which is the detect stackable bodies. We have three different scopes.

We have the base phase scope, which points to that phase highlighted in blue. We have the base edge scope, which points to all those lines in the same phase. And we can continue in that way our model. Moving to the sixth task, we can create a size field.

This is the way we are going to define our element size. This is equivalent to sizing in the machine, normal workflow. In this case, we have by default a curvature sizing, but I want to add an additional control to define a constant size on that face.

To do so, I am going to right click and insert constant sizing and instead of using value, I can select an outcome from a previous task, but this is not the right one. I want to choose the face in the base size.

That's why I can go to labels and select the base face label, apply to scoping pattern, and apply selection. Doing so, I have here the right selection and I can modify the element size I want to include.

Instead of settings, I am going to use value 0.5 mm, it's a good number, and I can create the size field. I don't have any visual outcome, but I can move to the next task where I am going to create the mesh surface. And in that way, I can see how the machine is going.

Then I can see I have two controls here and the size field surface measures I am going to let it as it is but in the quad mesh advanced options I am going to change the triangle reduction mode to aggressive to have as much as quad as possible Then I am going to execute this step and I can see now I have my mesh.

Let's just take a look. and we can see how all the details have been included in our 2D mesh and this is only for this phase we created as a base phase. Now we can move or we can extrude this mesh to create our three-dimensional mesh.

This is made in the eighth step which is the mesh volume 1. I can expand it and I see we have the volume meshing and we have all the scopes defined from the previous steps. I am going to let it as they are but I want to add a new task which is the number of divisions on edge.

That will allow me to control the number of elements through the thickness for all the parts. In this case, instead of using value, I will use outcome again and I will let it for the mesh parts. meaning I want to modify all the bodies except the non-stackable ones. And I want to use three divisions.

Then I can execute that step and now we have a three-dimensional mesh. And please see we have three elements through the thickness in all the parts, except for the solder joints.

And then the final task will be delete the two-dimensional mesh we used to define all the remaining because we don't need it anymore. I am just going to execute this step and now I have my 3D mesh for all the assembly I wanted from the beginning.

Finally, I am going to just output the workflow to return control to the model.

This is just complete workflow and now we can see we have the mesh which is a regular mesh as created by any other method and we also can see we have the geometry, the original geometry which is silent but we have the new geometry which is created from the workflow.

This is all the steps we need to perform to create this kind of meshes for your electronics application. I hope you will find it interesting. Thank you for watching! Please contact us at https://ozeninc.com/contact for more information.