Invariant analysis with conservation laws for the time fractional Drinfeld-Sokolov-Satsuma-Hirota equations

In this paper, the invariance properties of time fractional coupled Drinfeld-Sokolov-Satsuma-Hirota (DSSH) equations have been investigated using the Lie group analysis method. In this regard a systematic research to derive Lie point symmetries of time fractional coupled DSSH equations is performed. Using the Lie group analysis method, the vector fields and the symmetry reduction of the time fractional coupled DSSH equations are obtained. It is shown that, the time fractional coupled DSSH equations can be reduced to the fractional coupled ordinary differential equations by using fractional Erdelyi-Kober differential operator with Riemann-Liouville derivative. Finally using new conservation theorem with formal Lagrangian, the new conserved vectors are well constructed with a detailed derivation, which present the conservation analysis for time fractional coupled Drinfeld-Sokolov-Satsuma-Hirota (DSSH) equations. (C) 2017 Elsevier Ltd. All rights reserved.