A Comparison of ANSYS Fluent Meshing and Ansys Meshing for CFD

If you have ventured into Computational Fluid Dynamics (CFD), you know that the meshing process can be laborious, but critical to the solve-time and solution accuracy. You may have also noticed that there are a lot of meshing tools to choose from, and while it is tempting to think of them as a commodity, they certainly are not. The types of meshes and the workflows available in the tool can make or break your simulation (and your mood). 

Ansys Meshing and Ansys Fluent Meshing are the two most used Ansys meshing tools for CFD. It is thus useful to learn about the commonality and difference between the two. Common questions new (and existing users) have are:

  • How do the two tools fit into the Ansys CFD workflow?
  • How are the two tools different?
  • When is one tool preferred over the other?

Let us start with how these two fit into the Ansys CFD workflow. In particular, let us cover how both integrate with Ansys Workbench.

Ansys Meshing Workbench Integration

Ansys meshing is a staple of the workbench environment. Its physics-aware mesh settings allow you to tailor meshes for Electromagnetics, Structural FEA, CFD, etc. One can drag a mesh component system onto the project or bring it in as part of an analysis system. Figure 1 shows Ansys meshing component in Workbench as well as the CFD analysis systems with Ansys meshing. It is seamless.

Figure 1: Ansys Meshing Workbench Integration

Fluent Meshing Workbench Integration

Many users use Fluent Meshing in standalone mode instead of Workbench as part of the “New Fluent Experience Workflow.” However, Fluent meshing is available in Workbench as well. You can import Fluent Meshes to Polyflow and CFX, not only Fluent. Note that to do so, one must enable the beta feature in the workbench options as shown in Figure 2 to allow connections between Fluent Meshing and Polyflow or CFX.

Figure 2: Fluent Meshing Workbench Integration

Meshing Topologies

Fundamental to meshing is cell topology. It is important to first note that Fluent meshing is a strictly 3D mesher, while Ansys meshing can generate 2D and 3D meshes. In 3D, both tools can generate meshes with tet, hex, prism/wedge, and pyramid elements. Fluent’s Mosaic Meshing technology sets itself apart by leveraging conformal polyhedron elements. Polys offer advantages over tets in that they greatly reduce cell count, offer good gradient calculations because of the additional faces, while still being easy to use for complex geometries.

Figure 3: 3D Element Types, Polyhedrons are Only Available in Fluent Meshing

Conformal vs Nonconformal Meshes

Keep in mind that not all CFD tools are compatible with non-conformal meshes. Reminder, conformal meshes match every node to a node in the adjacent cells. Ansys CFD tools can handle non-conformal mesh mapping at interfaces i.e. a coarse solid mesh interface with a fine fluid mesh. However, CFX and Polyflow are not compatible with non-conformal cell structures like standard Fluent meshing hex-core meshes with 1/8 octree transitions. Do not worry though, Fluent meshing users can now easily fill in these transitions with pyramids via the advanced setting “Avoid 1/8 octree transition” and thus achieve a conformal cell structure.  

Figure 4: Fluent Meshing Conformal Hex-Core is Compatible with Ansys CFX and Polyflow

Volume Mesh Methods

The volume mesh methods available in these two tools have some commonality but also significant differences. Often the decision as to which tool should depend on which mesh method is most appropriate for your geometry and your real-world constraints like computing power, project deadlines, accuracy requirements, etc. For example, if your manager comes by your desk and tells you he wants a rough estimate for pressure drop through a manifold by the end of the day, you probably do not have time to block off a structured mesh with perfect boundary layer resolution. Figures 5 and 6 provide a high-level comparison of the methods available in both tools and you should use them to guide you as you plan your CFD model.

Figure 5: Ansys Meshing Volume CFD Mesh Methods

Figure 6: Fluent Meshing Volume Mesh Methods

Meshing Workflows

So how do you use these tools? Let us review that next because while the general steps are similar, the workflow from cad to finished mesh differs significantly.

Ansys Meshing Workflow

I would sum up the Ansys meshing workflow as flexible, parametric, and iterative. It is flexible in that you can mix/match mesh methods for different bodies and sequence them as you wish. Your control of the mesh can be as simple as accepting the physics-aware global mesh control defaults or you can take a fine comb and specify edge, node, face, body sizing, etc. in any sequence to achieve mesh refinement exactly where you want it. It is parametric in that you can have all controls be driven by user-defined name selections. These name selections can be automated based on size/ location/ associativity via the worksheet tool allowing you to update your geometry and have mesh settings propagate through. Lastly, it is iterative because you can generate the mesh for sections of the model, check quality metrics, and iterate until the mesh is ready for analysis.

Figure 7: Ansys meshing Workflow

Fluent Meshing Task-Based Workflows

Two task-based workflows are available in Fluent meshing and they cover most use cases: Watertight and Fault-Tolerant. These workflows guide users step by step through the meshing process beginning with geometry and import and ending in volume mesh generation. These workflows are customizable and can be saved to be re-used in future analyses.

Figure 8 compares the two workflows at a high level. As the names suggest, the watertight workflow is used for fluid and/or solid geometry that is relatively clean and watertight. Most users opt for this workflow when they are fortunate enough to have clean geometry or after using the capable geometry clean-up tools in Ansys Spaceclaim.

However, sometimes CAD is very dirty and/or composed of many parts that make it a laborious undertaking to clean up. The fault-tolerant meshing (FTM) workflow excels here. FTM can be used with all major CAD formats like STL, JT, etc. The best way to visualize FTM for external flow applications is to picture shrink wrapping a car. For internal flow, picture blowing up a balloon inside the part. The “wrapping” process covers up small leakages and errors in the CAD. You use the wrap to build a surface mesh and then a volume mesh.

Figure 8: Fluent Meshing Task-Based Meshing Workflows

Usability Features

Figure 9 lists some notable usability features in both tools to consider when deciding which tool is best for the project. The list is of course not exhaustive, but those listed are notable when it comes to having an efficient meshing experience. 

Figure 9: Comparison of Usability Features in Ansys Meshing and Fluent Meshing


To summarize, both Ansys Meshing and Fluent Meshing generate high quality meshes and they provide convenient usability features for efficient and accurate CFD analysis.

Notable differences between the two include:

  • Cell types/ Methods:
    • Fluent Meshing’s Mosaic-Enabled Parallel Poly-Hexcore Meshing combines high geometry fidelity, cell quality and fast solve time.
    • Ansys Meshing Sweep and Multi zone meshing enable users to create structured (primarily) hex meshes with intuitive control and flexibility.
  • Workflows
    • Fluent Meshing’s task-based workflows are easy to use and tailored to the most common CFD applications.
    • Ansys Meshing provides a flexible environment allowing users to leverage smart physics-based global controls while also providing detailed local mesh control.
  • Usability Features
    • Fluent meshing offers the ability to create custom workflows that can include journal files, local sizing and automatic mesh improvement tasks.
    • Ansys meshing worksheets enable mesh operation recording and name selection definition based on size, location, or topology for mesh control

Some readers are likely still interested in the answer to the blunt question: Which tool should I use?

Well, it depends:

  • When using Fluent to solve, the Poly-Hexcore mesh topology offers a clear advantage making Fluent Meshing the likely choice.
  • When using CFX or Polyflow, you can still leverage conformal hex-core meshing or tetrahedral meshes in Fluent Meshing, but the robust integration of Ansys meshing with CFX/ Polyflow makes it the preferred tool.
  • If a structured hex mesh is needed or preferred to minimize mesh size or to align the mesh with the flow direction everywhere, then Ansys meshing offers a more user-friendly environment for this topology via sweep or multizone meshing.

Signal & Power Integrity Updates in Ansys 2021 R1 – Webinar

The use of Ansys Electronics solutions minimizes the testing costs, ensures regulatory compliance, improves reliability and drastically reduces your product development time. All this while helping you build the best-in-class and cutting-edge products.

With signal and power integrity (SI & PI) analysis products, users can mitigate many electrical and thermal issues affecting printed circuit boards such as electromagnetic interference, crosstalk, overheating, etc. Ansys integrated electromagnetics and circuit simulation tools are essential for designing high-speed serial channels, parallel buses, and complete power delivery systems found in modern high-speed electronic devices.

Leverage the simulation capability from Ansys to solve the most critical aspects of your designs. Join PADT’s Electronics expert and application engineer Aleksandr Gafarov for a detailed look at what is new for SI & PI in Ansys 2021 R1, including updates available within the following tools:

• SIwave – Granta support & differential time domain crosstalk

• Q3D – Uniform current terminals

• Circuits – Network data explorer & SPISim

• HFSS 3D – Parallel meshing, encrypted 3D components & IC workflow improvements

• Electronics Desktop – Ansys cloud, Minerva & optiSLang integration

• And much more

Register Here

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You will only have to do this once! For all future webinars, you can simply click the link, add the reminder to your calendar and you’re good to go!

Ansys Mechanical Selection Information: Even More Useful Than We Thought

I have always known that the Selection Information window is extremely useful, giving us properties like Surface Area, Edge length, and the distance between two selected nodes.

But it will also do a few things that I had not known about, until recently. 

Normally you can Export the Nodal Locations with a solution result plot, but for that you have to solve the model first. If you have not yet solved the model, you can still get the nodal locations using the Selection Information window, though it is a little finicky.

  1. Open the Selection information window from the Home tab.
  1. Select all the nodes by selecting one node and hitting CTRL-A.
  1. In the Selection Information window, click the ‘Node ID’ header to sort by Node ID number.
  1. Select the first cell of the data you want.
  1. Scroll all the way to the bottom of the Window, and while holding down the Shift key, select the last row of the adjacent columns that you want to select.
  1. Once selected, right-click on it and hit “Export Text File”, or “Copy” and then Paste the data into Excel.

The trick is that the “Export Text File” and “Copy” do not show up if you pick the headers to select the entire columns like you do in Excel.

You can do the same thing to thing to get the mass properties of an assembly.

Selecting bodies will give you the mass, centroid, and principal moments of inertia. You can get this in the Worksheet view when the Geometry branch is highlighted.  Unlike the Worksheet, however, we can change the options to show the Moments of inertia about a given coordinate system.

We can now export out the six moments of inertia about any given coordinate system.  Next, I will attempt the find the ACT calls to do the same thing.   Stay tuned…

All Things Ansys 087: Introducing Rocky DEM – The latest in 3D Discrete Element Modeling Technology


Published on: May 3rd, 2021
With: Eric Miller, Robert McCathren, Ahmad Haidari & Marcus Reis

In this episode your host and Co-Founder of PADT, Eric Miller is joined by PADT’s Application Engineer, Robert McCathren, as well as Ahmad Haidari – Senior Director of Strategy & Business Development at Rocky DEM, and Marcus Reis – VP of Sales, Support & Marketing at Rocky DEM to discuss the company’s partnership with Ansys and what their tool is capable of.

Rocky is a powerful 3D Discrete Element Modeling (DEM) Particle Simulation Software that quickly and accurately simulates the flow behavior of bulk materials with complex particle shapes and size distributions, for typical applications such as conveyor chutes, mills, mixers, and other materials handling equipment.

If you have any questions, comments, or would like to suggest a topic for the next episode, shoot us an email at podcast@padtinc.com we would love to hear from you!



Simulation Workflow from Ansys Electronic Desktop Circuit to Ansys HFSS

ANSYS Electronics Desktop (AEDT) is a collection of powerful tools for simulation. AEDT Circuit provides time domain as well as frequency domain analyses. AEDT Circuit has high execution speed and robust ability to handle circuits of active and passive elements. Analysis types range from DC, Linear Networks (frequency domain), Transient, Oscillator, TV Noise, Envelope, Harmonic Balance, VerifEye (Statistical Eye Diagram), AMI Analysis, and more, with integrated support for additional co-simulation with tools like HSPICE or Matlab. Follow arturoherrera to get access for Matlab courses.

AEDT Circuit also provides an easy way to create and simulate planar structures such as microstrip, stripline, coupled lines, co-planar strips, co-planar waveguides, and other Printed Circuit Board (PCB) elements which can then be converted into a physical layout of the PCB. In this blog a simple workflow is explained to generate and model a planar structure in Circuit, then export the circuit model to HFSS 3D layout and HFSS for further analysis.

Define your substrate:

After inserting a Circuit Design, right-click on Data under project tree, choose Add Substrate Definition. This brings you to Substrate Defintion window that gives you many optios of substate types. You can choose the type of substarte you need and enter the dielectric and trace metalization information as shown in Figure 1. This substrate is used in calucalation of line impedances.



Figure 1. (a) Substrate Definition options of substrate types, (b) the definition of strapline used in this blog.

Define your stackup:

The stackup in Circuit is very similar to the stackup in HFSS 3D Layout. Please note that the definition of substrate is not automatically transferred to the stackup. The stackup needs to be defined by the user. Select the Schematic tab and from the top banner choose Stackup. Then define each layer. This stackup will be used in creating the layout and transferring it to HFSS 3D Layout.  Figure 2 shows the stackup used for the FR4 substrate that was defined in Figure 1(b).

Figure 2. Stackup definition that will be used to transfer the layout to HFSS 3D Layout.

Create the circuit:

Circuit provides a large selection of component libraries. To see the Component Libraries, click on View and check Component Libraries. In the Component Libraries window look for Distributed and expand it. Under this category you see different types of PCB structures. We will use Stripline library. Expanding Stripline library there are various categories, including Transmission Lines. We need Transmission Line Physical Length component, as we would like to use pieces of transmission line to create an ideal branch line coupler. You notice by hovering the cursor on the name of the component a small information windows shows the symbol and information about the component, alternatively you can right-click on the name of the component and choose “View Component Help” to get to the complete help page about the component. Once a component is selected and placed in the circuit it will also appear under the Project Components list at the bottom of the Component Libraries list. This provides a quick way to reuse them (Figure 3).

Figure 3. (a) Component Libraries, (b) Project Components and information window.

Let’s choose a physical length transmission line and place it on the schematic window. By double clicking on the symbol the Properties window opens and can be modified. Explicit values or parameters can be used to define the line properties.

Are you starting to calculate the line impedance to figure out the dimensions? Wait, there is a tool here that helps you do that. Click on TRL to open the line calculator. The line can be synthesized based on its impedance and electrical size by choosing the correct frequency and clicking on Synthesize (Figure 4). Using physical length transmission lines (50 and 35 ohms) and Tee lines and 4 ports I created an ideal branch line coupler (Figure 5). I ran a frequency analysis to make sure the circuit is working properly.

Before moving on to export the layout to HFSS 3D layout we can do one more step. To keep the substrate definition and reuse it layer, click on File->Save As Technology File. This would save the definition of stripline substrate in the personal library. Next step is to export the layout to HFSS 3D layout.

Figure 4. Properties and TRL windows.

Figure 5. Branch line coupler schematic.

Export to HFSS 3D Layout:

Under Schematic tab, click on Layout, or from the top menu choose Circuit->Layout Editor. Notice that this layout editor is very similar to the HFSS 3D Layout window. Click Ctrl+A, to select everything. Then choose Draw form the top banner and click on Align MW Ports (Figure 6), notice that other tools are also available under Draw, such as Sanitize Layout and Geometry Healing. You might need to do a bit more corrections and cleaning before exporting the layout. Before exporting the geometry, you can also check the HFSS Airbox using Layout->Draw HFSS Airbox.

Figure 6. Aligning ports.

You may change the orientation to Isometric for a better view of the box (Figure 7).

Figure 7. Layout editor in Isometric orientation, showing the HFSS airbox.

Make sure everything is still selected or select them with Ctrl+A, then under Edit, choose Copy to HFSS 3D Layout.  Now an HFSS 3D Layout design is created. Open the design. There might be a few things you like to change. Expand the ports, the name of the ports might have changed. You also note that the ports are of Gap type. You can select the port and in the Properties window, under HFSS click on Gap and choose the Wave port. Just note that the wave port cannot be internal to the design. You might need to adjust the air box size or create PEC port caps in HFSS later.

The second point to consider is about the parameters defined in Circuit. Remember that we defined W35 and W50 as the line widths in Circuit. The parameter are transferred but several local variables are also created based on them. For example click on the 50 ohm line. The width is now shown as a new parameter. You can see the complete list of parameters that are created by choosing HFSS 3D Layout->Design Parameters. Under the Parameters Default you still see W35 and W50, but moving to Local Variables tab you see the parameters created based on the Parameters Default.

Figure 8. Properties window.

Export to HFSS:

Any HFSS 3D Layout design can be exported to HFSS. Click on Analysis from the project three. Right-click and Add HFSS Solution Setup (Figure 9). There is no need to run this analysis. It just needs to be created. Right-click on the HFSS Setup that was just created, select Export->HFSS Model (Figure 10). Select the name and location for this file. Open this file and examine the model. Notice that the parameters are not transferred to HFSS model, this is because all parts of the model are imported (Figure 11). The default ports (Gap ports) appear as lumped port. If you changed the Gap ports to Wave ports in HFSS 3D Layout, it is now the time to add the PEC port caps or change the airbox to make sure ports are not internal to the model.

Figure 9. Adding HFSS solution setup.

Figure 10. Exporting the layout to an HFSS model.

Figure 11. HFSS model.

It is important to note that the type of analysis in Circuit is different than HFSS which will lead to slightly different result (Figure 12), which is expected and emphasizes the value of simulating structures in a full-wave field simulator like HFSS.



Figure 12. (a) Branch-line coupler S parameters from Circuit model, (b) the imported HFSS branch-line coupler S parameters.


This was a short blog showing the workflow for importing PCB and planar designs from AEDT Circuit to HFSS 3D Layout and HFSS. The workflow is a good method to quickly create the HFSS model of a planar structure.

If you would like more information related to this topic or have any questions, please reach out to us at info@padtinc.com.

Project Management for Non-Linear Dynamics Simulation with ANSYS LS-DYNA

We spend a lot of time writing articles about how to use the very capable tools that are available from Ansys, Inc., but tend to skip over the project management side of simulation. But, project management can be as important, especially for challenging simulations, as the technical aspects.  We recently completed a series of Non-Linear Dynamics simulations with ANSYS LS-DYNA and ended up learning a lesson or two about how to get such projects done on time and on budget. Follow korucaredoula to get access to the series.

What is Non-Linear Dynamics Simulation, and what makes it different?

When materials are deformed so fast that the rate of strain changes material properties, we refer to that as non-linear dynamics. In non-linear structural simulation, the material may be distorting in a non-linear way (usually plasticity), but the non-linear properties are dynamic. Because of this, time gets involved in the equation, as do non-linear material properties.  Think car crash, metal forming, drop, bird impact on windshields and jet engine blades, and bullets going through stuff. 

There are various software tools in the Ansys family that can do the non-linear dynamics, but our preferred program is Ansys LS-Dyna.  It is an explicit dynamics solver that solves structural, fluid, thermal, and other physics.  It is an amazing program that does many things. Still, for the class of problem we are talking about here, we only care about time-dependent material non-linearity for structural deformation.

Setting expectations

Before beginning a project of any type, it is important to establish goals.  Non-linear dynamics is no different. What is different is that you have to be realistic about what goals you can achieve.  The events you are modeling are, by their very nature are very, well, non-linear. The answers you calculate can change drastically with mesh, loads, material properties, and solver parameters.

If you need high accuracy, then you need to set the expectation that it will take longer to solve, and you have to be more careful with your model. If you don’t need accuracy and you may be looking for relative improvements, like seeing if one geometry option makes things better or worse in your design, then you can back off and be less detailed.  This difference can have a large impact on your schedule and overall cost.

So before you plan, before you start gathering information, decide what you expect to get out of your model.

Planning for the Job

Once you have set your expectations and goals, it’s time to map out the project. It is not that different from most structural or vibration jobs. You still have to get geometry, create a mesh, define loads and constraints, apply material models, run, and post processes.

However, each of those steps can be different for non-linear dynamics.  Here are some critical issues to be aware of when producing a schedule:

  • Geometry
    If you are working with thin, especially sheet metal, parts, you probably want to use shells. They are more efficient and can be more accurate in many situations. You need to not just have a CAD model, but also a model that has the mid-plane surface defined as well as thicknesses.

    You also want to look at removing tiny features that don’t impact the solution.  The run time in an explicit dynamic solver is driven by the smallest element size. If you have tiny features relative to your overall geometry, capturing them can drive up your run times.  So set aside time to remove or simplify them.
  • Meshing
    As mentioned above, small elements can drive up run time. Also, distorted elements or elements that become distorted can cause your solutions to diverge and fail. You may (probably) need to create a hexahedral (brick) mesh.  All of these things require more time to create the mesh, and from a project standpoint, you need to plan for that.
  • Contact
    Ansys LS-Dyan rocks at contact.  It is pretty much automatic in most cases. So here, you don’t have to set aside time to define and tweak your contacts to get convergence. But there are many options, including erosion and other fancy options. Understand your contact needs and track and manage them.
  • Loads
    Everything in LS-DYNA is time-dependent, and loads are no exception.  If you are lucky, your load or loads are constant over time. But if not, you need to set aside time to characterize those loads and get them specified in the right format.  In addition, loads can be calculated, say the results of an explosion or an airbag deployment. These use Equation of State models to calculate forces on the fly and are a major advantage of the tool.
  • Solving
    From a project management standpoint, it is very important to plan for relatively long solves, restarts, and if possible, solving several jobs at the same time.  Non-linear dynamics is computationally intense. Do some trade studies on computer resources vs. schedule time.  Is it worth investing in more cores to solve faster or just let it chug away on a smaller computer? Also, don’t assume a single run to get the answer you want. Often you need to run the model multiple times before you understand what is really going on.

  • Post-processing
    We are solving highly non-linear events, and understanding what the model is telling us is the whole point of the exercise.  Budget time for processing massive amounts of data over time and reducing it into something useful. Also, time is needed to create animations.  The analyst may also find themselves buried in the weeds at the post-processing stage, and project management should take on the role of reviewing the results from a big picture perspective and drive what tables, graphs, plots, and animations are created.

Keeping the project on the rails when things are literally blowing up and crashing

The dynamic nature of both the events being modeled and the process of creating and running the models make for a less predictable progression for the project.  A project manager needs to pay close attention to what is going on at all times and pull the engineers doing the work back up for air to find out where things are going. 

Here are some things to watch out for:

  • Building a model that is more complex than needed
  • Making sure that the situation being simulated in the model is what the customer needs simulated
  • Too much time being spent to fit the model on a limited computer. Get a bigger computer.
  • The simulation engineer is fixated on details that don’t impact the solution much
  • Oversimplification of components, connections, and loads.
  • Science project mode – spending time trying to learn basic information or trying to get something new to work, and not solving a specific problem.

One of, if not the most important roles for the project manager is communication.  Constantly interacting with the engineers (without nagging) and with the customer (the person who will consume the results) is critical.  This is not a throw-it-over-the-wall type of project.  And the more you accomplish, often the more you have new questions.  It may take two weeks or nine months. But either way, the PM needs to be constantly talking to everyone involved.

And yes, here at PADT, we have actually modeled a train car going off the rails. The project, though, stayed on track because we kept a close watch and stayed focus on the specifications. Things did surprise us, and we had to change some of the model when we got the first results, but we planned for that, communicated with the customer, and kept our changes to what was needed to answer the customer’s questions.

Our cars have incredible crash safety, very few planes fail because of bird ingestion, and we create amazing components out of formed sheet metal because of this type of non-linear dynamic simulation, and in most cases, Ansys LS-Dyna. Proper project management that recognizes the challenges and differences for this type of project can make a massive variety of products even better.

Electronics Reliability Updates in Ansys 2021 R1 – Webinar

Best practices for ensuring and predicting electronics reliability require comprehensive multi-physics simulations. Ansys ensures reliability success by developing solutions and workflows that overcome today’s biggest simulation and design challenges. 

With Ansys 2021 R1, electronics reliability became much easier to manager with advanced capabilities for design democratization, workflow automation, and robust reliability predictions. Along with these updated components, users can better access integrated workflows between Ansys Sherlock, Icepak, Mechanical, LS-Dyna, and more to provide the results necessary to optimize product designs and ensure unparalleled reliability in the field. 

Join PADT’s Systems Application & Support Engineer Josh Stout for a presentation covering updates to existing features and the introduction of new tools available in this latest release. Learn how users can:

• Extract detailed geometries from any ECAD file

     • Predict time to failure before prototyping

     • Perform complex multiphysics analyses

     • Implement automation and optimization 

     • And much more

Register Here

If this is your first time registering for one of our Bright Talk webinars, simply click the link and fill out the attached form. We promise that the information you provide will only be shared with those promoting the event (PADT).

You will only have to do this once! For all future webinars, you can simply click the link, add the reminder to your calendar and you’re good to go!

All Things Ansys 086: Thermal Integrity in Ansys 2021 R1


Published on: April 20th, 2021
With: Eric Miller & Josh Stout

In this episode your host and Co-Founder of PADT, Eric Miller is joined by PADT’s Systems Application & Support Engineer, Josh Stout in order to discuss what is new with regards to thermal integrity in Ansys 2021 R1.

If you have any questions, comments, or would like to suggest a topic for the next episode, shoot us an email at podcast@padtinc.com we would love to hear from you!



Mechanical Analysis Updates in Ansys 2021 R1 – Webinar

Ansys 2021 R1 delivers significant improvements in simulation technology together with nearly unlimited computing power to help engineers across all industries reimagine product design and achieve product development goals that were previously thought impossible. 

With updates made to Ansys mechanical, users can easily handle the complexity of a variety of design environments. Everything from mulitphysics analysis to dynamic simulation allows for the ability to create a product that meets performance goals and holds up over time. 

Join PADT’s Application Engineer Robert McCathren for a look at analytical advancements in Ansys Mechanical 2021 R1, including updates for: 

          ​​​​• Element Technology

          • NonLinear Adaptivity

          • Coupled Physics Analysis

          • Linear Dynamics

          • Contact

          • And much more

Register Here

Running Ansys Fluent on Ansys Cloud using a Journal File and a UDF

Cloud computing is becoming more and more popular with the recent changes in the work environment, and Ansys Cloud solution is no exception. While running a Fluent simulation on the Ansys Cloud is now a more familiar task among CFD users since its introduction around a year ago, there are still some cases that might be challenging and need more attention. One of these cases is performing a Fluent simulation using a UDF.

The first thing users might notice when launching an Ansys Cloud Fluent job through the ACT extension is that the UDF files won’t be uploaded, which is why they might see their cases are failing if they don’t pay extra attention. In order to avoid this issue, users must follow one of the options below.

The first and most commonly used method to launch a Fluent job with a UDF is via the CLI (Command Line Interface). With this method, the .c and all other files in the working directory will be uploaded to the Cloud. Then UDF will then be compiled on the Cloud.

Since the Cloud computers already have compilers installed, one doesn’t need to anything special. The local directory should have .c file, case file with UDF plugged-in, and a journal file. As a side note, Ansys Fluent 19.3 and higher supports expressions that can be used to define boundary conditions instead of UDF. Starting with Ansys Fluent 2020R2, the C compiler is built-in with the software. Please refer to the product documentation.

We highly recommend that the user should have the required compiler installed locally to compile, hook, and test the routine before submitting it to the cloud.

If you have not used CLI to submit a Fluent job to the clouds, please read the article below:


In short, you have to open a command prompt (cmd.exe) and navigate to your working folder. This folder should contain all the Fluent input files needed for the run: journal file, case file, etc. Once you login using ansyscloudcli command, you are ready to submit your job on the cloud.

Below is a common example for the commands to run Fluent on the cloud:

ansyscloudcli runfluent -j fluent_via_journal --jou tjunction.jou –q Flexible_eastus_Standard_HC44rs_2020r2 -n 1 -m 36 -v 2020r2

Here is some description of these commands:

> AnsysCloudCLI runFluent -j <job name> [--jou <journal>] -q <queue>  [-n <num nodes>] [-m <max cores>] -v <solver version>
-j: job name
-q: name of the queue 
    (run: ansyscloudcli getQueues, to get a list of all queues. Queue name is case sensitive)
-i: name of the input file for the solver
--jou: journal to execute (if set, -i is not used)
-n: number of nodes
-m: (optional) max number of cores. Useful if you want to make a run with 4 cores on a computer with 16 cores
-v: target solver version

The second method is to compile the UDF locally and upload all files to a virtual desktop infrastructure (VDI) session. Then the compiled UDF can be used with Fluent through the VDI session. Note that the UDF can’t be compiled on a VDI session with versions 2020R2 and earlier.

Lastly, with 2021R1 Fluent has a built in Clang compiler which will allow you to compile a UDF in a VDI session. However, the Clang compiler still won’t allow you to submit a Fluent job with a UDF through the ACT.

Ansys Cloud VDI solution running on a local desktop via RDP

All Things Ansys 085: Additive & Structural Optimization Updates in Ansys 2021 R1


Published on: April 5th, 2021
With: Eric Miller & Doug Oatis

In this episode your host and Co-Founder of PADT, Eric Miller is joined by PADT’s Lead Mechanical Engineer, Doug Oatis in order to discuss what is new with regards to additive and structural optimization in Ansys 2021 R1.

If you have any questions, comments, or would like to suggest a topic for the next episode, shoot us an email at podcast@padtinc.com we would love to hear from you!



Thermal Integrity Updates in Ansys 2021 R1 – Webinar

With CAD-centric (mechanical and electrical CAD) and multiphysics user interfaces, Icepak facilitates the solving of today’s most challenging thermal management problems in electronics products and assemblies. Icepak uses sophisticated CAD healing, simplification and metal fraction algorithms that reduce simulation times, while providing highly accurate solutions that have been validated against real-world products.

This tool provides powerful electronic cooling solutions that utilize the industry leading Ansys Fluent computational fluid dynamics solver for thermal and fluid flow analyses of integrated circuits, packages, printed circuit boards, and electronic assemblies.

With the release Ansys 2021 thermal integrity capabilities saw improvements in a variety of areas. Join PADT’s Application & Support Engineer and Thermal Integrity expert Josh Stout to learn more about recent advancements surrounding: 

• Solar Radiation Modeling

     • Robust Meshing Distribution

     • Dynamic Thermal Management

     • The Release of AEDT Mechanical Solutions

     • And Much More

Register Here

If this is your first time registering for one of our Bright Talk webinars, simply click the link and fill out the attached form. We promise that the information you provide will only be shared with those promoting the event (PADT).

You will only have to do this once! For all future webinars, you can simply click the link, add the reminder to your calendar and you’re good to go!

All Things Ansys 084: The State of Mechanical Meshing in Ansys 2021


Published on: March 22nd, 2021
With: Eric Miller & Joe Woodward

In this episode your host and Co-Founder of PADT, Eric Miller is joined by PADT’s Senior Mechanical Engineer and Lead Trainer, Joe Woodward in order to discuss what new mechanical meshing capabilities are available in Ansys 2021.

Meshing is an integral part of the engineering simulation process where complex geometries are divided into simple elements that can be used as discrete local approximations of the larger domain. The mesh influences the accuracy, convergence and speed of the simulation. Furthermore, since meshing typically consumes a significant portion of the time it takes to get simulation results, the better and more automated the meshing tools, the faster and more accurate the solution.

If you have any questions, comments, or would like to suggest a topic for the next episode, shoot us an email at podcast@padtinc.com we would love to hear from you!



Additive & Structural Optimization Updates in Ansys 2021 R1 – Webinar

The most powerful simulation solution for metal additive manufacturing, the Ansys Additive Suite delivers the critical insights required by designers, engineers and analysts to avoid build failure and create parts that accurately conform to design specifications. This comprehensive solution spans the entire workflow — from design for additive manufacturing (DfAM) through validation, print design, process simulation and exploration of materials.

Ansys 2021 R1 delivers enhancements across all portfolio products — Ansys Additive Prep, Ansys Additive Print, Ansys Additive Science and Ansys Workbench Additive — empowering users to further advance their additive manufacturing capabilities.

Join PADT’s Simulation Support & Application Engineer Doug Oatis for a webinar covering both the structural optimization and additive updates made to Ansys 2021 R1 including enhancements for: 

  • Process Simulation

  • Part Qualification

  • Design for AM

  • Build Setup

  • Shape & Lattice Optimization

  • And much more

Register Here

If this is your first time registering for one of our Bright Talk webinars, simply click the link and fill out the attached form. We promise that the information you provide will only be shared with those promoting the event (PADT).

You will only have to do this once! For all future webinars, you can simply click the link, add the reminder to your calendar and you’re good to go!

All Things Ansys 083: Digital Mission Engineering & the Acquisition of AGI


Published on: March 8th, 2021
With: Eric Miller, Anthony Dawson & Paul Graziani

In this episode your host and Co-Founder of PADT, Eric Miller is joined by Anthony Dawson, Vice President & General Manager at Ansys, and Paul Graziani, CEO and Co-Founder of Analytical Graphics, Inc. (AGI) to discuss the acquisition of AGI and what it means for those simulating in the aerospace and defense industry.

Digital mission engineering, pioneered by AGI, combines digital modeling, simulation, testing, and analysis for aerospace, defense, telecommunication, and intelligence applications to evaluate mission outcomes at every phase of a system’s life cycle. Using this tool you can evaluate the full effect of every change you make and find problems before they become crises.

If you have any questions, comments, or would like to suggest a topic for the next episode, shoot us an email at podcast@padtinc.com we would love to hear from you!