EBI-DNScode

OpenFOAM^® is a widely used, flexible, easy to extend and powerful toolkit for computational fluid dynamics simulations that provides additional tools for pre and postprocessing. It has a number of solvers dedicated to the simulation of combustion processes. These solvers suffer from some shortcomings:

• No detailed models for molecular diffusion are available. Instead, a unity Lewis number is assumed for all species.
• The computation of chemical reaction rates from finite rate models uses OpenFOAM's^® solvers for ordinary differential equations (ODE). Compared to other ODE solvers, they run much slower.

In order to overcome these shortcomings and to provide an OpenFOAM^® based solver that can compute flames both accurately as well as efficiently, the EBI-DNS solver was created. It was first developed in 2012 and has been improved ever since. It couples OpenFOAM^® to the open-source library Cantera. This enables the use of Cantera's detailed model for diffusion coefficients. This also means that reaction mechanisms can be provided to the OpenFOAM^® solver in Cantera's xml format. The integration of chemical reaction rates is performed by Sundials CVODE solver, which is the only third-party dependency of the EBI-DNS solver. Compared to OpenFOAM's^® own ODE solvers, this was found to speedup chemistry computation by a factor of ten, depending on the setup.

The EBI-DNS solver itself is based on OpenFOAM's^® rhoReactingBuoyantFoam solver. It extends the solver by additional features and also changes the transport equations for species masses and energy, because the species can diffuse with different velocities. OpenFOAM^® is used in version v1712 or 5.x and the interface is based on Cantera's version 2.5.0a2