stroemung

A Computational Fluid Dynamics (CFD) simulator in Rust.

Intro

stroemung implements a 2D fluid dynamics simulation based on Numerical Simulation in Fluid Dynamics: A Practical Introduction by M. Griebel, T. Dornseifer, and T. Neunhoeffer, as well as NaSt2D, its associated C implementation.

stroemung is also inspired by khanhn201/flow2d-rs by @khanhn201.

Some project goals of stroemung are:

• Physically accurate simulation of the simplified fluid dynamics problems presented in Numerical Simulation in Fluid Dynamics.
• Reliance on ndarray's higher-order iterators instead of indexing, where possible.
• Avoidance of branching code in inner loops, where possible.
• Integration and unit testing of linear algebra primitives, boundary condition setup routines, pressure solver and overall simulation steps [still in progress].
• Numerical comparison against the reference NaSt2D where appropriate.

Name

Die Strömungsmechanik, Fluidmechanik oder Strömungslehre ist die Wissenschaft vom physikalischen Verhalten von Fluiden. -- Wikipedia

Status

• Currently shows a basic GUI with a simulation grid preset based on flow past an obstacle.
• The linear algebra primitives and some of the simulation steps have been implemented and tested against reference values from NaSt2d.
• The other parts of the implementation have been written, but not completely tested.
• Some methods are documented, most are not.
• The Python scripts to generate NaSt2D problem files and parse their outputs are partially implemented.

Installation

Cargo

• Install the rust toolchain in order to have cargo installed by following this guide.

Running

It is highly recommended to run in release mode, since the simulation can be computationally demanding.

cargo run --release

Click "Run / Pause" to start the simulation, or "Run one simulation step" to iterate one step.

You can draw boundary or fluid cells with the mouse by clicking on the appropriate buttons. Note that the simulation doesn't allow for boundary cells that have fluid on opposite sides. If you attempt to paint fluid cells that create such a boundary, the drawing tool will simply reject it. If you create a weird boundary pattern that you can't delete, just paint over it with boundary cells again or reset the simulation.

Some simulation parameters can be adjusted from the command-line, see

cargo run --release -- --help

for details. For example, to increase the Reynolds number of the simulated fluid to 400, run:

cargo run --release -- --reynolds 400

Generating test data

There is a Python script in the python/ directory which will generate test data from the NaSt2D program. See python/README.md for more details.

License

Licensed under the MIT license.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the MIT license, shall be licensed as above, without any additional terms or conditions.

See CONTRIBUTING.md.