Scalability of OpenFOAM Density-Based Solver with Runge–Kutta Temporal Discretization Scheme
Algorithm 1
The Eulerian fluxes are calculated explicitly so that the ordinary differential equations system can be constructed and further integrated in time by using explicit Runge–Kutta algorithm.
Result: construct Eulerian fluxes explicitly
while runTime.loop() do
Saving quantities at preavious time steps if rk4 then
/ The following firstly constructs the Eulerian fluxes by applying the Kurganov and Tadmor (KT) scheme. /
surfaceScalarField phi
(“phi,”
());
surfaceVectorField phiUp
(“phiUp,”
(
+ );
surfaceScalarField phiEp
(“phiEp,”
(
+
+ ));
/ Then, the divergence theorem (Gauss’s law) is applied to relate the spatial integrals to surface integrals.