What are some of the best practices and tips for setting up and running CFD and FSI cases?

1 Choose the right software

Depending on your problem, you may need different types of software to perform CFD and FSI simulations. For example, you may need a solver that can handle multiphase flows, turbulence models, moving boundaries, or coupled physics. You may also need a pre-processor that can generate high-quality meshes, a post-processor that can visualize and extract results, and a coupling tool that can transfer data and forces between the fluid and the solid domains. Therefore, you should research and compare the features, capabilities, and limitations of various software packages before choosing the one that suits your needs.

2 Define the problem and the objectives

Before you start setting up your CFD and FSI case, you should have a clear definition of the problem and the objectives of your simulation. What are the physical phenomena that you want to capture and understand? What are the boundary conditions and the initial conditions that you need to apply? What are the outputs and the performance indicators that you want to measure and optimize? Having a clear problem statement and a well-defined scope will help you to plan and execute your simulation more efficiently and effectively.

3 Validate and verify your model

One of the most important steps in CFD and FSI simulation is to validate and verify your model. Validation means comparing your simulation results with experimental data or analytical solutions to check the accuracy and the realism of your model. Verification means ensuring that your model is free of errors and that your results are converged and consistent. You should perform validation and verification at every stage of your simulation, from meshing to solving to post-processing. This will help you to identify and correct any mistakes, uncertainties, or discrepancies in your model.

4 Optimize your mesh and your solver

Another crucial step in CFD and FSI simulation is to optimize your mesh and your solver. The mesh is the discretization of the computational domain into smaller elements or cells. The quality and the size of the mesh affect the accuracy and the speed of your simulation. You should use a mesh that is fine enough to capture the important features and gradients of the flow and the structure, but not too fine that it increases the computational cost and time. You should also use a mesh that is compatible with your solver and your coupling tool. The solver is the algorithm that solves the governing equations of the fluid and the solid domains. The choice and the settings of the solver affect the stability and the convergence of your simulation. You should use a solver that can handle the complexity and the nonlinearity of your problem, and that can be tuned and customized to improve its performance.

5 Analyze and interpret your results

The final step in CFD and FSI simulation is to analyze and interpret your results. This means using the post-processor to visualize and extract the relevant data and information from your simulation. You should use appropriate tools and methods to display and compare your results, such as plots, graphs, contours, vectors, animations, or statistics. You should also use critical thinking and reasoning to explain and understand the physical mechanisms and the trends behind your results. You should also evaluate the reliability and the significance of your results, and identify any limitations or uncertainties in your model.