多德-布洛-米哈伊洛夫方程

多德-布洛-米哈伊洛夫方程(Dodd-Bullough-Mikhailov equation)是一个非线性偏微分方程^[1]。

$u_{xt}+\alpha *e^{u}+\gamma *e^{-2*u}=0$

行波解

多德-布洛-米哈伊洛夫方程不是函数u的多项式形式，因此必须做代换：

$v=e^{u}$ , 变为：

$v*v_{xt}-v_{t}*v_{x}+\alpha *v^{3}+\gamma =0$

得到函数v(x,t)的行波解： $v(x,t)=(1/2)*\gamma ^{(}1/3)+(3/2)*\gamma ^{(}1/3)*cot(_{C}1+_{C}2*x-(3/4)*\gamma ^{(}1/3)*t/_{C}2)^{2}$ $v(x,t)=(1/2)*\gamma ^{(}1/3)-(3/2)*\gamma ^{(}1/3)*coth(_{C}1+_{C}2*x+(3/4)*\gamma ^{(}1/3)*t/_{C}2)^{2}$ $v(x,t)=(1/2)*\gamma ^{(}1/3)+(3/2)*\gamma ^{(}1/3)*tan(_{C}1+_{C}2*x-(3/4)*\gamma ^{(}1/3)*t/_{C}2)^{2}$ $v(x,t)=(1/2)*\gamma ^{(}1/3)-(3/2)*\gamma ^{(}1/3)*tanh(_{C}1+_{C}2*x+(3/4)*\gamma ^{(}1/3)*t/_{C}2)^{2}$ $v(x,t)=-(1/4)*\gamma ^{(}1/3)-(1/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3)+(-(3/4)*\gamma ^{(}1/3)-(3/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*cot(_{C}1+_{C}2*x+(3/4)*((1/2)*\gamma ^{(}1/3)+(1/2*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*t/_{C}2)^{2}$ $v(x,t)=-(1/4)*\gamma ^{(}1/3)-(1/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3)+(-(3/4)*\gamma ^{(}1/3)-(3/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*tan(_{C}1+_{C}2*x+(3/4)*((1/2)*\gamma ^{(}1/3)+(1/2*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*t/_{C}2)^{2}$ $v(x,t)=-(1/4)*\gamma ^{(}1/3)-(1/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3)+((3/4)*\gamma ^{(}1/3)+(3/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*coth(_{C}1+_{C}2*x+(3/4)*(-(1/2)*\gamma ^{(}1/3)-(1/2*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*t/_{C}2)^{2}$ $v(x,t)=-(1/4)*\gamma ^{(}1/3)-(1/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3)+((3/4)*\gamma ^{(}1/3)+(3/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*tanh(_{C}1+_{C}2*x+(3/4)*(-(1/2)*\gamma ^{(}1/3)-(1/2*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*t/_{C}2)^{2}$

作反变换： $u(x,t)=ln(v(x,t))$

即得多德-布洛-米哈伊洛夫方程的行波解：

$u(x,t)=ln((1/2)*\gamma ^{(}1/3)+(3/2)*\gamma ^{(}1/3)*cot(_{C}1+_{C}2*x-(3/4)*\gamma ^{(}1/3)*t/_{C}2)^{2})$ $u(x,t)=ln((1/2)*\gamma ^{(}1/3)-(3/2)*\gamma ^{(}1/3)*coth(_{C}1+_{C}2*x+(3/4)*\gamma ^{(}1/3)*t/_{C}2)^{)}$ $u(x,t)=ln((1/2)*\gamma ^{(}1/3)+(3/2)*\gamma ^{(}1/3)*tan(_{C}1+_{C}2*x-(3/4)*\gamma ^{(}1/3)*t/_{C}2)^{2})$ $u(x,t)=ln((1/2)*\gamma ^{(}1/3)-(3/2)*\gamma ^{(}1/3)*tanh(_{C}1+_{C}2*x+(3/4)*\gamma ^{(}1/3)*t/_{C}2)^{2})$ $u(x,t)=ln(-(1/4)*\gamma ^{(}1/3)-(1/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3)+(-(3/4)*\gamma ^{(}1/3)-(3/4*I)*{\sqrt {(}}3)*\gamma (1/3))*cot(_{C}1+_{C}2*x+(3/4)*((1/2)*\gamma ^{(}1/3)+(1/2*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*t/_{C}2)^{2})$ $u(x,t)=ln(-(1/4)*\gamma ^{(}1/3)-(1/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3)+(-(3/4)*\gamma ^{(}1/3)-(3/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*tan(_{C}1+_{C}2*x+(3/4)*((1/2)*\gamma ^{(}1/3)+(1/2*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*t/_{C}2)^{2})$ $u(x,t)=ln(-(1/4)*\gamma ^{(}1/3)-(1/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3)+((3/4)*\gamma ^{(}1/3)+(3/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*coth(_{C}1+_{C}2*x+(3/4)*(-(1/2)*\gamma ^{(}1/3)-(1/2*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*t/_{C}2)^{2})$ $u(x,t)=ln(-(1/4)*\gamma ^{(}1/3)-(1/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3)+((3/4)*\gamma ^{(}1/3)+(3/4*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*tanh(_{C}1+_{C}2*x+(3/4)*(-(1/2)*\gamma ^{(}1/3)-(1/2*I)*{\sqrt {(}}3)*\gamma ^{(}1/3))*t/_{C}2)^{2})$

行波图

参考文献

^ 李志斌编著《非线性数学物理方程的行波解》第105-107页，科学出版社 2008

*谷超豪《孤立子理论中的达布变换及其几何应用》上海科学技术出版社
*阎振亚著《复杂非线性波的构造性理论及其应用》科学出版社 2007年
李志斌编著《非线性数学物理方程的行波解》科学出版社
王东明著《消去法及其应用》科学出版社 2002
*何青王丽芬编著《Maple 教程》科学出版社 2010 ISBN 9787030177445
Graham W. Griffiths William E.Shiesser Traveling Wave Analysis of Partial Differential p135 Equations Academy Press
Richard H. Enns George C. McCGuire, Nonlinear Physics Birkhauser,1997
Inna Shingareva, Carlos Lizárraga-Celaya,Solving Nonlinear Partial Differential Equations with Maple Springer.
Eryk Infeld and George Rowlands,Nonlinear Waves,Solitons and Chaos,Cambridge 2000
Saber Elaydi,An Introduction to Difference Equationns, Springer 2000
Dongming Wang, Elimination Practice,Imperial College Press 2004
David Betounes, Partial Differential Equations for Computational Science: With Maple and Vector Analysis Springer, 1998 ISBN 9780387983004
George Articolo Partial Differential Equations & Boundary Value Problems with Maple V Academic Press 1998 ISBN 9780120644759

[1] 李志斌编著《非线性数学物理方程的行波解》第105-107页，科学出版社 2008

[1]