Geometry Preparation using Ansys Discovery — Lesson 1

CFD analysis is an important tool used in the design and optimization of FSAE cars. Preparing geometry for meshing and simulation involves several steps to ensure that the geometry is suitable for further analysis. Complex geometries often contain intricate details that are not essential for the analysis. In such cases, simplifying the geometry can significantly reduce the computational resources and time required for meshing and simulation. This simplification can involve removing small features, combining or merging surfaces, or simplifying curves.

Repairing the geometry ensures that it is topologically valid and suitable for mesh generation. Geometry repair involves identifying and fixing issues such as gaps, overlaps, self-intersections, or nonmanifold edges. In addition to repairing obvious issues, the geometry may require further cleanup and healing to ensure its integrity. This can involve removing small sliver surfaces, smoothing or simplifying curves, aligning and connecting disjointed surfaces, and ensuring the geometry is watertight. Through this three-part lesson, we will understand this process of simplifying and repairing the geometry using Ansys Discovery.

To learn more about the basic tools used for geometry preparation in Ansys Discovery, please refer to the course Geometry Prep for CFD Simulation using Ansys Discover here.

Simulation Files

Download the files here to follow the video step-by-step. Student teams can apply for a free research license here.

CAD Simplification Using Ansys Discovery — Lesson 1, Part

In this lesson, using practical and physics-based justifications, we will identify some simplifying assumptions that we can implement to transform the original, complex FSAE CAD geometry into a CFD-simulation friendly geometry. We will make use of Ansys Discovery for modifying the car geometry. Along the way, we will also learn how to utilize various tools such as Fill, Combine, Move, and more.

Alternate video link.

CAD Repair Using Ansys Discovery — Lesson 1, Part 2

In this lesson, we will learn how to repair the simplified FSAE CAD by detecting and fixing any geometry-based issues that may create problems during meshing using Ansys Discovery. We will learn about the contents of the Repair and Prepare tabs and how to use various tools available under them, such as Solidify Surface Bodies, Fix Edge and Faces, Interference, etc., to aid in the CAD repair process

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CAD Preparation Using Ansys Discovery — Lesson 1, Part 3

In this lesson, we will learn how to prepare the simplified FSAE CAD for meshing to perform an external aerodynamic analysis. We will look at how to create fluid enclosure around the car, create separate fluid regions around the wheels for implementing moving reference frame conditions, and apply the Share Topology tool between the different fluid regions to ensure conformal mesh generation between the fluid regions during meshing. Finally, we will learn how to create named selections for different parts of the car, which is very useful during meshing, solver setup, and post-processing.  

Alternate video link.