Mixed Hermite-Legendre Spectral Method Proposed for Kinetic Plasma Simulations
Researchers have proposed a hybrid spectral method combining Hermite and Legendre polynomial expansions for solving kinetic collisionless plasma equations. The mixed approach is designed to handle both near-Maxwellian distributions and strongly non-Maxwellian features like beams and plateaus more efficiently than either method alone. This advancement could improve computational accuracy in plasma physics simulations while maintaining practical computational costs.
A new mixed spectral method for kinetic plasma simulations combines Hermite polynomials (traditionally used for near-Maxwellian distributions) with Legendre polynomials (better suited for non-Maxwellian features). The method is particularly advantageous for problems where non-Maxwellian features are localized in velocity space. The researchers demonstrate both analytically and numerically that the mixed method conserves total mass, momentum, and energy through imposed constraints. Numerical results show that for the same number of degrees of freedom, the mixed method achieves improved accuracy compared to using either Hermite or Legendre methods individually, while maintaining comparable computational cost.
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- arXiv physicsCenter
Mixed Hermite-Legendre spectral method for kinetic plasma simulations
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