SBIR-STTR Award

A New Hybrid Method for High-Order EM-PIC Simulations
Award last edited on: 10/9/2008

Sponsored Program
SBIR
Awarding Agency
DOD : AF
Total Award Amount
$600,970
Award Phase
2
Solicitation Topic Code
AF071-009
Principal Investigator
Tian Xiao

Company Information

Wave Computation Technologies Inc

1800 Martin Luther King Jr Parkway Suite 204
Durham, NC 27707
   (919) 360-6475
   tianxiao@wavenology.com
   www.wavenology.com
Location: Single
Congr. District: 04
County: Durham

Phase I

Contract Number: ----------
Start Date: ----    Completed: ----
Phase I year
2007
Phase I Amount
$100,000
We propose to prototype and test a new 3-D hybrid technique that combines two efficient algorithms, (a) the discontinuous Galerkin pseudospectral time-domain (DG-PSTD) method and (b) the boundary conformal finite-difference time-domain (BC-FDTD) method, as a high-order solver for electromagnetic particle-in-cell (EM-PIC) simulations. This hybrid technique overcomes the well-known limitation of existing EM-PIC solvers due to their stair-stepping approximation. The proposed hybrid method uses domain decomposion to divide the problem into DG-PSTD regions with coarse structures and BC-FDTD regions with fine structures. As the DG-PSTD method has spectral accuracy and the BC-FDTD method has second-order accuracy, the overall convergence of this EM-PIC solver is better than second order. The team has already developed the most relevant techniques for the pure electromagnetics problem in an existing commercial prototype, Wavenology EM Pack, and has worked on plasma simulations. The proposed 3-D hybrid numerical EM-PIC solver will be integrated into this commercial prototype. It promises to effectively mitigate spurious effects caused by the stair-stepping approximation in the EM-PIC simulation.

Keywords:
Electromagnetic Particle-In-Cell (Em-Pic) Simulation, Hybrid Technique, Pseudospectral Time-Domain Method, Finite-Difference Time-Domain Method,High P

Phase II

Contract Number: ----------
Start Date: ----    Completed: ----
Phase II year
2008
Phase II Amount
$500,970
Wave Computation Technologies, Inc. (WCT) proposes to develop a new commercial electromagnetic particle-in-cell (EM-PIC) software package based on a 3-D hybrid technique that combines two efficient algorithms, (a) the enlarged cell technique (ECT) and (b) the spectral-element time-domain (SETD) method, as a high-order solver for EM-PIC simulations. This hybrid technique overcomes the well-known limitation of existing EM-PIC solvers due to their stair-stepping approximation. The proposed hybrid method uses domain decomposition to divide the problem into SETD regions with coarse structures and ECT regions with fine structures. As the SETD method has spectral accuracy and the ECT method has second-order accuracy, the overall convergence of this EM-PIC solver is better than second order. In Phase I the team has already developed and demonstrated the prototype of this method. Specifically, we have integrated the ECT with the particle-in-cell calculation, and have achieved the second-order global convergence. The typical computation time for a problem with 5.45 million cells and 1600 time steps is approximately 14 minutes on a desktop computer (Pentium-D 2.8GHz, only 1 CPU is used). This speed is believed to be unprecedented. In Phase II, the proposed 3-D hybrid numerical EM-PIC solver will be integrated into an existing commercial platform to produce a new commercial package, Wavenology PIC. It promises to effectively mitigate spurious effects caused by the stair-stepping approximation in the conventional EM-PIC simulation method. The commercial code will be complete with particle emission and propagation. The algorithm will be scalable, stable and globally at least second order accurate for curved geometries. Issues such as self force, grid heating, non-physical radiation and self heating will be mitigated to globally second-order convergence.

Keywords:
Particle-In-Cell (Pic),Electromagnetic (Em),Simulation,Conformal,Boundary