Solving Boltzmann and Fokker-Planck Equations Using Sparse Representation

Abstract

The main objectives of this project is to develop efficient and accurate spectral methods for fractional PDEs and high-dimensional problems. Fractional partial differential equations (FPDEs) appear in the investigation of transport dynamics in complex systems which are governed by the anomalous diffusion and non-exponential relaxation patterns. The main difficulties for dealing with fractional differential equations are: (i) fractional derivatives are non-local operators; (ii) fractional PDEs in space are usually derived in unbounded domains and their solutions exhibit slow algebraic decay at infinity; (iii) when truncated to finite domains, fraction derivatives involve singular weight functions and the solutions of FPDEs are usually singular near the boundary. We developed several efficient approaches to deal with these problems. The main difficulty for solving high-dimensional problems is how to break the curse of dimensionality. We continued our work in developing fast sparse spectral methods for solving a class of moderately high dimensional elliptic equations in bounded and unbounded domains. Many complex nonlinear systems can be described as gradient flows. We developed a class of extremely efficient numerical methods for solving a large class of gradient flows.

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Document Details

Document Type
Technical Report
Publication Date
Apr 09, 2019
Accession Number
AD1085893

Entities

People

  • Jie Shen

Organizations

  • Purdue University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Boundaries
  • Boundary Value Problems
  • Chebyshev Functions
  • Differential Equations
  • Equations
  • Fokker Planck Equations
  • Formulas (Mathematics)
  • Galerkin Method
  • Laguerre Functions
  • Nonlinear Systems
  • Partial Differential Equations
  • Polynomials
  • Scientific Research
  • Universities
  • Wave Equations

Fields of Study

  • Mathematics

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Calculus or Mathematical Analysis

Technology Areas

  • Space