PoPe (Projection on Proper elements) for code control: verification, numerical convergence and reduced models. Application to plasma turbulence simulations

TL;DR

PoPe is a new method for code verification, convergence assessment, and error characterization in simulations, applicable across dimensions and regimes, demonstrated on plasma turbulence models.

Contribution

The paper introduces PoPe, a novel approach for code control that verifies models, assesses convergence, and designs reduced models with low computational cost.

Findings

PoPe effectively verifies plasma turbulence simulations.

It quantifies residual errors and convergence properties.

It aids in designing efficient reduced models.

Abstract

The Projection on Proper elements (PoPe) is a novel method of code control dedicated to 1) checking the correct implementation of models, 2) determining the convergence of numerical methods and 3) characterizing the residual errors of any given solution at very low cost. The basic idea is to establish a bijection between a simulation and a set of equations that generate it. Recovering equations is direct and relies on a statistical measure of the weight of the various operators. This method can be used in any dimensions and any regime, including chaotic ones. This method also provides a procedure to design reduced models and quantify the ratio costs to benefits. PoPe is applied to a kinetic and a fluid code of plasma turbulence.