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Divergence preservation in the ADI algorithms for electromagnetics. (English) Zbl 1175.78029

Summary: The recent advances in alternating direct implicit (ADI) methods promise important new capability for time domain plasma simulations, namely the elimination of numerical stability limits on the time step. But the utility of these methods in simulations with charge and current sources, such as in electromagnetic particle-in-cell (EMPIC) computations, has been uncertain, as the methods introduced so far do not have the property of divergence preservation. This property is related to charge conservation and self-consistency, and is critical for accurate and robust EMPIC simulation. This paper contains a complete study of these ADI methods in the presence of charge and current sources. It is shown that there are four significantly distinct cases, with four more related by duality. Of those, only one preserves divergence and, thus, is guaranteed to be stable in the presence of moving charged particles. Computational verification of this property is accomplished by implementation in existing 3D-EMPIC simulation software. Of the other three cases, two are verified unstable, as expected, and one remains stable, despite the lack of divergence preservation. This other stable algorithm is shown to be related to the divergence preserving case by a similarity transformation, effectively providing the complement of the divergence preserving field in the finite-difference energy quantity.

MSC:

78M20 Finite difference methods applied to problems in optics and electromagnetic theory
78M25 Numerical methods in optics (MSC2010)

Software:

VORPAL

References:

[1] Zheng, F.; Chen, Z.; Zhang, J., Toward the development of a three-dimensional unconditionally stable finite-difference time-domain method, IEEE Microwave Theory Tech., 48, 1050-1058 (2000)
[2] Lee, J.; Fornberg, B., Some unconditionally stable time stepping methods for the 3D Maxwell’s equations, J. Comput. Appl. Phys., 166, 497 (2004) · Zbl 1034.78019
[3] Strang, G., On the construction and comparison of difference schemes, SIAM J. Numer. Anal., 5, 3, 506 (1968) · Zbl 0184.38503
[4] L.H. Thomas, Elliptic problems in linear difference equations over a network, Watson Sci. Comput. Lab. Rept., Columbia University, New York, 1949.; L.H. Thomas, Elliptic problems in linear difference equations over a network, Watson Sci. Comput. Lab. Rept., Columbia University, New York, 1949.
[5] Hockney, R. W.; Eastwood, J. W., Computer Simulation Using Particles (1988), Hilger · Zbl 0662.76002
[6] Birdsall, C. K.; Langdon, A. B., Plasma Physics Via Computer Simulation (1991), Hilger
[7] Villaseñor, J.; Buneman, O., Rigorous charge conservation for local electromagnetic field solvers, Comput. Phys. Commun., 69, 306 (1992)
[8] Esirkepov, T. Zh., Exact charge conservation scheme for particle-in-cell simulation with an arbitrary form-factor, Comput. Phys. Commun., 135, 144-153 (2001) · Zbl 0981.78014
[9] Mardahl, P. J.; Verboncoeur, J. P., Charge conservation in electromagnetic PIC codes; spectral comparison of Boris/DADI and Langdon-Marder methods, Comput. Phys. Commun., 106, 219 (1997) · Zbl 0939.78009
[10] Yee, K. S., Numerical solution of initial boundary value problems involving Maxwell’s equations in isotropic media, IE Trans. Ant. Prop., 14, 302 (1966) · Zbl 1155.78304
[11] Nieter, C.; Cary, J. R., VORPAL: a versatile plasma simulation code, J. Comput. Phys., 196, 448 (2004) · Zbl 1115.76431
[12] Reference [6]; Reference [6]
[13] Dey, S.; Mittra, R., A locally conformal finite-difference time-domain FDTD algorithm modeling modeling three-dimensional perfectly conducting objects, IEEE Microwave Guided Wave Lett., 7, 273 (1997)
[14] Zagorodnov, I. A.; Schuhmann, R.; Weiland, T., A uniformly stable conformal FDTD-method in Cartesian grids, Int. J. Numer. Model., 16, 127 (1993) · Zbl 1014.78014
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