Reduced Run Times for Pressure-Based, Large Eddy Simulations Using Fourth Order, Implicit Time Integration

Abstract

Although Large Eddy Simulation (LES) is a promising approach for resolving flow physics and acoustics in turbulent-reacting flows, it has not yet made the transition to routine industrial use. The reason for limited use of unstructured LES for practical design analysis is the excessive turnaround times for LES, which results from the very small time steps and cell sizes required to resolve flow and acoustic features. In this study, we focused on implementing a fourth order accurate, implicit time integration scheme named Spectral Deferred Correction (SDC) to significantly reduce turnaround times from LES calculations in a pressure-based (SIMPLEC) Navier-Stokes solver. Sample calculations are presented that show the potential of an order of magnitude run time improvement for two test cases: 1) an acoustic wave reflecting in a frictionless duct, and 2) turbulent flow past an integral fuel injector/flame holder.