Title: A minimally-dissipative low-Mach number solver for complex reacting flows in OpenFOAM,
Abstract: Large eddy simulation (LES) has become the de-facto computational tool for
modeling complex reacting flows, especially in gas turbine applications.
However, readily usable general-purpose LES codes for complex geometries are
typically academic or proprietary/commercial in nature. The objective of this
work is to develop and disseminate an open source LES tool for low-Mach number
turbulent combustion using the OpenFOAM framework. In particular, a
collocated-mesh approach suited for unstructured grid formulation is provided.
Unlike other fluid dynamics models, LES accuracy is intricately linked to
so-called primary and secondary conservation properties of the numerical
discretization schemes. This implies that although the solver only evolves
equations for mass, momentum, and energy, the implied discrete equation for
kinetic energy (square of velocity) should be minimally-dissipative. Here, a
specific spatial and temporal discretization is imposed such that this kinetic
energy dissipation is minimized. The method is demonstrated using manufactured
solutions approach on regular and skewed meshes, a canonical flow problem, and
a turbulent sooting flame in a complex domain relevant to gas turbines
applications.