GridPro Version 9 Release Highlights!

Figure 1: GridPro Version 9 Feature Image.

1532 words / 7 minutes read

Introduction

In the ever-evolving landscape of grid generation, the goal of having an autonomous and reliable CFD simulation is the driving force behind progress. We’re thrilled to announce the release of GridPro Version 9, a major update that brings many new features, improvements, and powerful tools to empower users to achieve this vision. This release marks a significant milestone in our commitment to automate structured meshing. We have two new verticals released along with GridPro Version 9:

HexaMesh Volute – Vertical product that automatically meshes compressor, turbine, and pump volutes in less than 15 minutes.
HexaMesh Nuclear Rods – Vertical product to mesh nuclear rods with or without wires in PWR reactors.

This article presents a few highlights. To learn more about other features packed in Version 9, Check out the release notes and What’s New.

CAD Creation and Integration

To align ourselves with CFD_Vision_2030_Roadmap, we now use ESP as our modelling environment. With the introduction of this new environment, we aim to provide an adequate linkage between GridPro and the upfront CAD system. We have implemented a host of CAD creation tools, which enables users to create basic geometries in GridPro using the CAD panel.

[ New Feature ]: Grouping and Labelling of CAD Faces for Enhancing Workflow

As the first linking step in any Upfront CAD package, GridPro can import the labelling and grouping from any CAD package upstream through our improved STEP file format. The labels created in CAD software can be edited or inherited as surface and boundary labels in the mesh exported from GridPro, creating a seamless integration with the solver downstream.

Video 1: CAD Grouping and Labelling.

[ New Feature ]: CAD Label Based Surface Splitting

In GridPro Version 9, labelling/grouping can also be used to split the underlying surface mesh. In the previous version, surfaces were split to improve the volume mesh quality based on the feature angles, but now users can also split surfaces by utilizing surface labels/groups. This saves time and reduces the manual effort required to select multiple surfaces for splitting purposes.

Video 2: CAD Label-based Surface Splitting.

New Blocking Creation and Editing Features

[ New Feature ]: Block Once to Mesh all Similar Geometries

One of the significant challenges with traditional structured meshing is to dynamically update 3D blocking in the design and analysis of many engineering applications. Especially in scenarios involving shape optimization, moving boundary problems, etc. This requires the user to regenerate the blocks for every design change. It is a tedious and very time-consuming task to recreate a block structure after every design iteration.

GridPro, being a topology-based mesher, could readily accommodate geometry variations without any additional changes to the blocking. However, when geometries have non-uniform scaling, the parts of the block topology have to be moved close to the geometry to be mapped. This could become a time-consuming process, but with the introduction of the Block Mapping tool, the mapping can be done with a few clicks.

Mesh topologically similar geometries using Block Mapping tool in GridPro Version 9. — **Figure 2:** Topology Mapping Tool.

[ New Feature ]: Advanced Topology Block Smoother for Faster Meshing

GridPro’s flexible topology paradigm enables users to create blocks without any restrictions. This sometimes results in the user creating poorly shaped blocks. Though the mesh generation engine smooths the poorly shaped blocks, it increases the mesh convergence time. With the new topology, smoother, irregularly placed blocking is now repositioned to provide a better intuition and speed up the meshing time. With this new feature, the time for grid generation is significantly reduced by an order of magnitude in many cases.

Video 3: Enhanced block positioning by advanced Topology Block Smoother.

[ New Feature ]: Block Adaptation to Shock

To improve hypersonic simulation workflows, GridPro introduces a Shock Alignment feature. This innovation adapts the grid blocks to the shock formed in a baseline solution. By splitting blocks in the shock region and aligning the grid normal to the shock surface, the algorithm enhances simulation accuracy and accelerates convergence. This advancement allows users to achieve faster and more precise results, optimizing their computational fluid dynamics analyses. With GridPro’s Shock Alignment, engineers and researchers can tackle complex hypersonic flows more efficiently and reliably. (Check out the paper published in the AIAA Hypersonics Conference: A Shock Fitting Technique For Hypersonic Flows Using Hexahedral Meshes.)

**Figure 9: a.** Base grid. b. CFD post-processed result showing shock features. c. Extracted shock surface with the base grid. d. Blocks refined and aligned with the shock feature surface.

[ New Feature ]: Clamped Nesting for Enhanced Mesh Refinement

In GridPro, we have combined the benefits of unstructured meshing like local refinement, mesh adaptation, and multi-scale meshing by adapting the multi-block structure. This is done with a feature called Nesting, In this version we have released another flavour of nesting called the clamped nest. Clamped nesting aggressively refines the mesh near the geometry while coarsening it outside the region. This technique is particularly effective in creating highly refined regions, especially for LES and DNS simulations.

**Figure 8: a.** Clamp nesting block pattern. b. Clamp nested mesh around a turbine blade. c. Zoomed view showing the clamp nested mesh at one location.

[ Enhancement ]: Quick Blocking for Regular Patterns Using the Array-Block Feature

To speed up the block creation time for repeated geometries, an Array-block replication option is introduced. This provides the capability to replicate a topology in multiple directions. This tool is particularly advantageous when dealing with similar geometric patterns or shapes. Instead of creating the topology individually for each pattern, users can generate one pattern and seamlessly replicate it across self-similar geometric patterns in three different directions. Utilizing the Array feature, users can create blocking for a single periodic section and extend it in the X, Y, and Z directions.

Using 3D Array Tool, a topology can be copied in multiple directions. — **Figure 4:** 3D Array.

[ Enhancement ]: Generate, View, and Check Higher-Order Meshes

Starting now, the UI enables the creation of higher-order meshes with ease. Users can choose their preferred higher-order format – quadratic, cubic, or quartic – and the tool will automatically adjust the density to the nearest multiple of the selected order for seamless mesh generation.

Users can also import internally or externally generated higher-order grids into the UI for visualization and quality assessment. The meshes can be observed in various modes, including Only Edges, Edges with Corners, Edges with Nodes, and Edges with All Nodes, allowing for a comprehensive examination.

Moreover, users can evaluate mesh quality parameters such as the Jacobian of the higher-order elements and compare them to the native linear mesh for detailed analysis.

With GridPro Version 9, higher order meshes like quadratic, cubic and quartic can be generated. — **Figure 3:** Higher order meshes.

[ New Feature ]: Eliminating Negative Volumes with Local Block Smoothing.

The local block smoothing feature introduced in GridPro Version 9 provides the user a way to eliminate negative volumes ( folds) in the generated mesh locally. The local smoothing is a post-processing step which can be done in the grid to either improve the grid locally or to eliminate negative volumes.

The smoothing feature offers two schemes: Transfinite Interpolation (TFI) and Partial Differential Equation (PDE) smoothing. TFI-based smoothing is computationally less intensive, while PDE-based smoothing, despite its higher computational cost, proves more effective in areas with high curvature, producing meshes with fewer folds.

Grid block smoothing tool in GridPro Version 9 to enhance folds or elevate the mesh quality in user-selected blocks. — **Figure 5:** Mesh Smoothing.

[ Enhancement ]: GUI Access to Grid Schedule to Speedup Mesh Smoothing

In version 9, we provide GUI options to harness the control features in the Grid Schedule function. These are designed to accelerate mesh smoothing by leveraging the multi-grid capabilities of structured meshes. Particularly beneficial for large topologies, the approach involves initially running the topology at a lower density. Once the corners are approximately smoothed and positioned, the smoother can be executed for higher densities, contributing to accelerated grid convergence.

Users can insert additional steps to further customize the smoothing process, effectively breaking down the process into multiple stages. After each step, the smoothing computations automatically resume from the previous state, ensuring a seamless and efficient progression.

[ Enhancement ]: Enhanced Cut Plane Tool to Create Multiple Sectional Views

Now, users can generate multiple Cut Planes, allowing them to create sectional views at various locations and directions. The Cut Plane, employed to clip a portion of a surface or grid, facilitates the examination of its interior, mainly when the area to be meshed is situated inside the surfaces. The enhanced feature of utilizing more than one Cut Plane significantly simplifies the assessment of topology and mesh in complex areas.

Video 4: Multiple-cut planes feature facilitates better examination of topology and mesh in complex areas.

[ Enhancement ]: Python-based CAD and Meshing API

In version 9, we introduced the CAD and Meshing API with Python 3 support, empowering users to automate the meshing workflow with greater control. The updated API provides a comprehensive set of commands, including preprocessing and postprocessing operations. Repetitive tasks and batch operations can also be automated. This significantly reduces the user’s time spent on meshing and enhances productivity, particularly for new designs that follow similar workflows.

The new APIs can be tightly integrated with any CAD or optimization system, making them an excellent tool for automating topologically similar geometries. By leveraging the API, users can streamline their design process, ensuring efficient and consistent high-quality meshes and CFD results across different designs.

How to Get Your Hands on GridPro Version 9

Upgrading to GridPro Version 9 ! Existing users can easily upgrade to the latest version, while new users can explore the enhanced capabilities by downloading the software from https://www.gridpro.co m.

Visit our official website gridpro.com to download the latest version of GridPro!

To see these features in action, visit our Youtube Channel: GridPro Version 9 New Features Playlist.

Conclusion

As we continue to evolve and innovate, GridPro Version 9 reflects our commitment to providing you with the best tools and features to ease the workflow of mesh generation and accuracy of your CFD simulations. We believe these new features and tools will increase reliability and change how you mesh.