Ignis

Overview

Ignis is a C++ code for computing laminar premixed and diffusion flame profiles. Steady and unsteady solutions are possible, with soot formation and radiation models included.

Dependencies and installation

The code is intended to be built and used on Linux-like systems, including MacOS and the Linux subsystem for Windows.

Required software:

• CMake 3.15+
• C++17
• SUNDIALS
  • CVODE and KINSOL
• YAML
• SootLib
• RadLib

Optional software:

• Doxygen (for building documentation)
• graphviz (for Doxygen)

Build and installation instructions

1. Create and navigate into a top-level build directory
2. Configure CMake: cmake ..
3. Build Ignis: make
4. Install Ignis: make install

The build process installs the executable in run/ignis.x.

CMake configuration variables

The default CMake configuration should be adequate for users that do not immediately require the documentation. CMake configuration options can be set by editing the top-level CMakeLists.txt file, or specifying options on the command line during step 2 as follows:

cmake -DIGNIS_BUILD_DOCS=ON ..

Then build the documentation with make docs, and navigate to docs/index.html to view the documentation.

Using Ignis

Ignis is called from the command line with one of four command line options:

• ./ignis.x premixed
• ./ignis.x diffusion
• ./ignis.x diffusion_table
• ./ignis.x flamelet If no option is set the code defaults to premixed. Each of these options has a corresponding driver function that sets up and runs the case. The driver functions read case parameters from corresponding input files:
• input/input_premixed.yaml
• input/input_diffusion.yaml
• input/input_diffusion_table.yaml
• input/input_flamelet.yaml

Examples

The four case types, with the default input files function as four example cases for the code. They can be modified and extended as desired.

Flame formulations

Details of the equations solved and models used are given for

• Diffusion flames
• Premixed flames
• Diffusion flame table
• Laminar flamelets