A high-order public domain code for direct numerical simulations of turbulent combustion

TL;DR

This paper presents a high-order, publicly available numerical scheme implemented in the Pencil Code for direct numerical simulations of turbulent combustion, validated against established results and demonstrating high accuracy and effective boundary conditions.

Contribution

The paper introduces a fifth-order spatial scheme for turbulent combustion simulations in the Pencil Code, validated with hydrogen combustion and boundary condition implementation.

Findings

Fifth-order spatial accuracy verified.

Doubling resolution increases flame front accuracy 32-fold.

Boundary conditions validated for all directions.

Abstract

A high-order scheme for direct numerical simulations of turbulent combustion is discussed. Its implementation in the massively parallel and publicly available Pencil Code is validated with the focus on hydrogen combustion. Ignition delay times (0D) and laminar flame velocities (1D) are calculated and compared with results from the commercially available Chemkin code. The scheme is verified to be fifth order in space. Upon doubling the resolution, a 32-fold increase in the accuracy of the flame front is demonstrated. Finally, also turbulent and spherical flame front velocities are calculated and the implementation of the non-reflecting so-called Navier-Stokes Characteristic Boundary Condition is validated in all three directions.