PyPrometheus

PyPrometheus generates source code to compute chemical source terms. These source terms appear in the species conservation equations for reactive flows, so their implementation is needed for reactive-flow simulations.

Dependencies

Chemical source terms have models for reaction rates (e.g., Arrhenius rate coefficients) and thermodynamic properties (e.g., NASA polynomials). PyPrometheus manages source-term parameterization through Cantera (https://www.cantera.org). We recommend the latest version. There are no other dependencies.

Installation

Once you've installed Cantera, follow these steps to compile PyPrometheus.

• cd build
• Open makefile and substitute your local Cantera path in line 1.
• make

Note: a CMake-based build system is underway.

Running PyPrometheus

There are two steps to using PyPrometheus: (i) generating the models and (ii) using them in reactive flow simulations.

Generating source-term source code

Let's start with some preliminary definitions. We call the generated source code Prometheus thermochemistry kernels (PTK). To generate a PTK, we need an input config file. This file only needs to include two options:

• mech: The name of the mechanism. Note that this has to match the name of the Cantera input file. The only Cantera input format currently supported is cti.
• language: The language in which the source term will be implemented. PyPrometheus supports Python and C++. We provide an example (inputs/sample_inputs.config).

After customizinng the input file, we can generate a PTK by typing: build/Prometheus.exe <my_input.config> Prometheus will then produce a mech.py or mech.H.

Using generated PTKs (source code)

At this point, we have a PTK, but how do we even use it? We provide an in-depth tutorial via the jupyter notebook examples/tutorial_compute_source_terms.ipynb. Simply cd into tutorials and launch jupyter with jupyter notebook.

Authors

• Esteban Cisneros
• Michael Anderson