VARIATIONAL PRINCIPLE FOR (2 + 1)-DIMENSIONAL BROER–KAUP EQUATIONS WITH FRACTAL DERIVATIVES

Autor: Ya-Nan Guo, Shi-Cheng Hou, Xiao-Qun Cao, Cheng-Zhuo Zhang, Ke-Cheng Peng
Rok vydání: 2020
Předmět:
Zdroj: Fractals. 28:2050107
ISSN: 1793-6543
0218-348X
DOI: 10.1142/s0218348x20501078
Popis: This paper extends the [Formula: see text]-dimensional Broer–Kaup equations in continuum mechanics to its fractional partner, which can model a lot of nonlinear waves in fractal porous media. Its derivation is demonstrated in detail by applying He’s fractional derivative. Using the semi-inverse method, two variational principles are established for the nonlinear coupled equations, which up to now are not discovered. The variational formulations can help to study the symmetries and find conserved quantities in the fractal space. The obtained variational principles are proved correct by minimizing the functionals with the calculus of variations, and might find potential applications in numerical simulation. The procedure reveals that the semi-inverse method is highly efficient and powerful, and can be generalized to other nonlinear evolution equations with fractal derivatives.
Databáze: OpenAIRE