Spectral methods for two-dimensional space and time fractional Bloch-Torrey equations

Hong Lu; Ji Li; Mingji Zhang

doi:10.3934/dcdsb.2020065

Article Contents

2020, Volume 25, Issue 9: 3357-3371. Doi: 10.3934/dcdsb.2020065

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Spectral methods for two-dimensional space and time fractional Bloch-Torrey equations

1.
School of Mathematics and Statistics, Shandong University, Weihai, Shandong 264209, China
2.
School of Mathematics and Statistics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
3.
College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
4.
Department of Mathematics, New Mexico Institute of Mining and Technology, Socorro, NM 87801, USA

^* Corresponding author: Mingji Zhang
^* Corresponding author: Mingji Zhang

Received: May 2019

Revised: November 2019

Early access: April 2020

Published: September 2020

This work was supported the NSF of China (No. 11601278) and MPS Simons Foundation of USA (No. 628308)

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Abstract

In this paper, we consider the numerical approximation of the space and time fractional Bloch-Torrey equations. A fully discrete spectral scheme based on a finite difference method in the time direction and a Galerkin-Legendre spectral method in the space direction is developed. In order to reduce the amount of computation, an alternating direction implicit (ADI) spectral scheme is proposed. Then the stability and convergence analysis are rigorously established. Finally, numerical results are presented to support our theoretical analysis.

Keywords:

Space and time fractional Bloch-Torrey equations,
Legendre spectral method,
alternating direction implicit method,
stability and convergence.

Mathematics Subject Classification: Primary: 26A33, 65M70; Secondary: 65M12.

Citation:

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Figure 1. The left graph with $ \alpha = 0.3,\ \beta = 0.6 $ while the right one with $ \alpha = 0.8,\ \beta = 0.75 $ for Example 6.1

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Figure 2. $ \alpha = 0.5,\ \beta = 0.8 $ for Example 6.2

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Table 1. $ L^2 $ errors and convergence rates for Example 6.1

$ \tau $	$ \alpha=0.3\ \beta=0.6 $	Con. rate	$ \alpha=0.8\ \beta=0.75 $	Con. rate
1/10	1.4361e-004	2.1596	1.5512e-004	2.0231
1/20	3.2143e-005	2.0832	3.8163e-005	2.0046
1/40	7.5856e-006	2.0480	9.5104e-006	1.9942
1/80	1.8343e-006	1.9814	2.3872e-006	1.9743
1/160	4.6451e-007	1.7299	6.0791e-007	1.8456
1/320	1.4003e-007	-	1.6914e-007	-

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Table 2. $ L^2 $ errors and convergence rates for Example 6.2

$ \tau $	$ \alpha=0.3\ \beta=0.6 $	Con. rate	$ \alpha=0.8\ \beta=0.75 $	Con. rate
1/10	1.7946e-003	2.1361	1.6438e-003	2.0271
1/20	4.0827e-004	2.0638	4.0329e-004	2.0098
1/40	9.7653e-005	2.0361	1.0014e-005	1.9949
1/80	2.3810e-005	2.0142	2.5123e-005	1.9935
1/160	5.8943e-006	1.9872	6.3092e-006	1.9763
1/320	1.4867e-006	-	1.6034e-006	-

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References

[1]	A. A. Alikhanov, A new difference scheme for the time fractional diffusion equation, J. Comput. Phys., 280 (2015), 424-438. doi: 10.1016/j.jcp.2014.09.031.
[2]	C. Bernardi and Y. Maday, Spectral methods, in Handbook of Numerical Analysis, 5, North-Holland, Amsterdam, 1997, 209–485. doi: 10.1016/S1570-8659(97)80003-8.
[3]	W. Bu, Y. Tang, Y. Wu and J. Yang, Finite difference/finite element method for two-dimensional space and time fractional Bloch-Torrey equations, J. Comput. Phys., 293 (2015), 264-279. doi: 10.1016/j.jcp.2014.06.031.
[4]	A. Bueno-Orovio and K. Burrage, Exact solutions to the fractional time-space Bloch-Torrey equation for magnetic resonance imaging, Commun. Nonlinear Sci. Numer. Simul., 52 (2017), 91-109. doi: 10.1016/j.cnsns.2017.04.013.
[5]	V. J. Ervinand and J. P. Roop, Variational solution of fractional advection dispersion equations on bounded domains in $\mathbb{R}^d$, Numer. Methods Partial Differential Equations, 23 (2007), 256-281. doi: 10.1002/num.20169.
[6]	B. I. Henry, T. A. M. Langlands and S. L. Wearne, Anomalous diffusion with linear reaction dynamics: From continuous time random walks to fractional reaction-diffusion equations, Phys. Rev. E, 74 (2006), 15pp. doi: 10.1103/PhysRevE.74.031116.
[7]	A. A. Kilbas, H. M. Srivastava and J. J. Trujillo, Theory and Applications of Fractional Differential Equations, North-Holland Mathematics Studies, 204, Elsevier Science B.V., Amsterdam, 2006.
[8]	R. L. Magin, O. Abdullah, D. Baleanu and X. J. Zhou, Anomalous diffusion expressed through fractional order differential operators in the Bloch-Torrey equation, J. Magn. Reson., 190 (2008), 255-270. doi: 10.1016/j.jmr.2007.11.007.
[9]	R. Magin, X. Feng and D. Baleanu, Solving the fractional order Bloch equation, Concepts Magn. Reson., Part A, 34A (2009), 16-23. doi: 10.1002/cmr.a.20129.
[10]	R. Metzler and J. Klafter, The random walk's guide to anomalous diffusion: A fractional dynamics approach, Phys. Rep., 339 (2000), 1-77. doi: 10.1016/S0370-1573(00)00070-3.
[11]	K. S. Miller and B. Ross, An Introduction to the Fractional Calculus and Fractional Differential Equations, John Wiley & Sons, Inc., New York, 1993.
[12]	E. D. Nezza, G. Palatucci and E. Valdinoci, Hitchhiker's guide to the fractional Sobolev space, Bull. Sci. Math., 136 (2012), 521-573. doi: 10.1016/j.bulsci.2011.12.004.
[13]	I. Podlubny, Fractional Differential Equations. An Introduction to Fractional Derivatives, Fractional Differential Equations, to Methods of Their Solution and Some of Their Applications, Mathematics in Science and Engineering, 198, Academic Press, Inc., San Diego, CA, 1999.
[14]	J. P. Roop, Variational Solution of Fractional Advection Dispersion Equations, Ph.D. thesis, Clemson University in Clemson, SC, 2004.
[15]	J. Shen, Efficient spectral-Galerkin method. I. Direct solvers for second- and fourth-order equations using Legendre polynomials, SIAM J. Sci. Comput., 15 (1994), 1489-1505. doi: 10.1137/0915089.
[16]	J. Shen, T. Tang and L. L. Wang, Spectral Methods. Algorithms, Analysis and Applications, Springer Series in Computational Mathematics, 41, Springer, Heidelberg, 2011. doi: 10.1007/978-3-540-71041-7.
[17]	Q. Yu, F. Liu, I. Turner and K. Burrage, Stability and convergence of an implicit numerical method for the space and time fractional Bloch-Torrey equation, Philos. Trans. R. Soc. Lond. Ser. A Math. Phys. Eng. Sci., 371 (2013), 18pp. doi: 10.1098/rsta.2012.0150.
[18]	Q. Yu, F. Liu, I. Turner and K. Burrage, Numerical investigation of three types of space and time fractional Bloch-Torrey equations in 2D, Cent. Eur. J. Phys., 11 (2013), 646-665. doi: 10.2478/s11534-013-0220-6.
[19]	Q. Yu, F. Liu, I. Turner and K. Burrage, A computationally effective alternating direction method for the space and time fractional Bloch-Torrey equation in 3-D, Appl. Math. Comput., 219 (2012), 4082-4095. doi: 10.1016/j.amc.2012.10.056.
[20]	Y. Zhao, W. Bu, X. Zhao and Y. Tang, Galerkin finite element method for two-dimensional space and time fractional Bloch-Torrey equation, J. Comput. Phys., 350 (2017), 117-135. doi: 10.1016/j.jcp.2017.08.051.