Low-storage, Explicit Runge-kutta Schemes for the Compressible Navier-stokes Equations

The derivation of low-storage, explicit Runge-Kutta (ERK) schemes has been performed in the context of integrating the compressible Navier-Stokes equations via direct numerical simulation. Optimization of ERK methods is done across the broad range of properties, such as stability and accuracy e ciency, linear and nonlinear stability, error control reliability, step change stability, and dissipation/dispersion accuracy, subject to varying degrees of memory economization. Following van der Houwen and Wray, sixteen ERK pairs are presented using from two to ve registers of memory per equation, per grid point and having accuracies from third to fth order. Methods have been tested with not only DETEST, but also with the 1D wave equation. Two of the methods have been applied to the DNS of a compressible jet as well as methane-air and hydrogen-air ames. Derived 3(2) and 4(3) pairs are competitive with existing full-storage methods. Although a substantial e ciency penalty accompanies use of twoand three-register, fth-order methods, the best contemporary full-storage methods can be nearly matched while still saving two to three registers of memory.