# Start Here Pyskyfire is a Python library for analysing liquid-propellant rocket engines. **Project links:** [GitHub](https://github.com/ask-hovik/pyskyfire) · [PyPI](https://pypi.org/project/pyskyfire/) It supports: * combustion-performance and nozzle-flow calculations using NASA CEA; * thrust-chamber and nozzle contour generation; * regenerative-cooling analysis of chamber walls and coolant channels; * cooling-channel geometry, wall-material, and coolant-property models; * pump, turbine, and engine-network utilities; * plots, interactive 3D geometry views, and standalone HTML reports. Pyskyfire is intended for preliminary engine design, thermal analysis, and engine-cycle studies. ## Start with the minimal simulation {doc}`Minimal Simulation ` is the recommended introduction to Pyskyfire. The tutorial builds and analyses a 5 kN nitrous-oxide/ethanol rocket engine. It shows how to: 1. define an engine design point; 2. calculate combustion-gas properties; 3. generate a thrust-chamber contour; 4. define walls and cooling channels; 5. run a regenerative-cooling simulation; and 6. generate plots, a 3D model, and an HTML report. The complete source code is available in `examples/minimal/minimal_sim.py`. Use it as a starting point for new engine cases. ## Documentation structure The documentation is organised around the [Diátaxis](https://diataxis.fr/) framework, with Validation added as a first-class section. Each section serves a different purpose. ### Tutorials Tutorials are guided, runnable introductions to a complete workflow. * {doc}`Minimal Simulation ` Build and analyse a regeneratively cooled thrust chamber from a defined engine design point. ### Howto Howtos guide you through achieving a specific goal. For example hoe to use pyskyfire to find an optimum mixture ratio: {doc}`Mixture ratio optimisation ` ### Validation Validation reports compare Pyskyfire analyses with published engine data. * {doc}`RL10A-3-3A ` Reconstruction and validation of the RL10A-3-3A thrust chamber, regenerative cooling system, and expander cycle. ### Explanations Explanations describe the engineering models, code structure, and analysis methods used by Pyskyfire. * {doc}`Capabilities ` Overview of the analyses, outputs, and visualisation tools provided by Pyskyfire. * {doc}`Package Structure ` Overview of the repository, source packages, examples, validation cases, and their roles. * {doc}`Regenerative Cooling ` Explanation of the regenerative-cooling model, solver structure, heat-transfer paths, and governing quantities. * {doc}`Specific Impulse and Thrust Coefficient ` Explanation of the vacuum, optimum-expansion, ambient, and sea-level performance figures, and the conditions under which each applies. * {doc}`The Moody Diagram ` Explanation of the friction-factor model used for cooling-channel pressure loss. * {doc}`Rao Nozzle Contour Angles ` Explanation of the angle data used to construct Rao-style bell nozzles. ### Reference The reference section is generated from the source code and documents the available Python interfaces. | Package | Purpose | | ---------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------- | | {doc}`pyskyfire.common ` | Shared objects including fluids, material models, result containers, stations, blocks, and engine-network infrastructure. | | {doc}`pyskyfire.skycea ` | NASA CEA-based combustion and aerothermodynamic calculations, nozzle utilities, and coolant transport properties. | | {doc}`pyskyfire.regen ` | Thrust-chamber geometry, cooling channels, wall models, regenerative cooling, and film cooling. | | {doc}`pyskyfire.pump ` | Pump and turbopump analysis utilities. | | {doc}`pyskyfire.turbine ` | Turbine models and utilities for engine-cycle calculations. | | {doc}`pyskyfire.viz ` | Plotting, reporting, pressure-temperature diagrams, and 3D engine visualisation. | Use the reference when you need the exact inputs, outputs, methods, or inheritance structure of a class or function. ## Documentation and source code Tutorials use runnable scripts from the repository. The minimal simulation tutorial includes selected sections of `examples/minimal/minimal_sim.py`, so the documented workflow matches the executed example. The API reference is generated from docstrings in `src/pyskyfire/`. ```{toctree} :maxdepth: 1 :titlesonly: :hidden: self ``` ```{toctree} :caption: Tutorials :maxdepth: 1 :titlesonly: :hidden: tutorials/minimal-simulation tutorials/advanced-simulation ``` ```{toctree} :caption: How-to Guides :maxdepth: 1 :titlesonly: :hidden: howto/mixture-ratio-optimisation ``` ```{toctree} :caption: Validation :maxdepth: 1 :titlesonly: :hidden: validation/rl10a-3-3a ``` ```{toctree} :caption: Explanations :maxdepth: 1 :titlesonly: :hidden: explanations/capabilities explanations/package-structure explanations/regenerative-cooling-explanation explanations/specific-impulse explanations/moody-diagram explanations/rao-nozzle ``` ```{toctree} :caption: Reference :maxdepth: 1 :titlesonly: :hidden: autoapi/pyskyfire/common/index autoapi/pyskyfire/regen/index autoapi/pyskyfire/pump/index autoapi/pyskyfire/turbine/index autoapi/pyskyfire/skycea/index autoapi/pyskyfire/viz/index ```