A direct numerical simulationHere the origin of the term direct numerical simulation (see e.g. p. 385 in ) owes to the fact that, at that time, there were considered to be just two principal ways of getting theoretical results regarding turbulence, namely via turbulence theories (like the direct interaction approximation) and directly from solution of the Navier–Stokes equations.https://eprints.soton.ac.uk/66182/1/A_primer_on_DNS.pdf "A Primer on Direct Numerical Simulation of Turbulence –