Dynamic analysis method and system for fractures in fracturing flowback and production stages of tight gas reservoir

The invention relates to a tight gas reservoir fracturing flowback and production stage crack dynamic analysis method, which comprises the following steps of: respectively establishing mechanical equilibrium equations by considering the opening state and the closing state of an artificial crack and a natural crack in a tight sandstone gas well exploitation process; increasing a fracture closing critical opening criterion; the Barree model is corrected, and an expression for calculating the closing opening degree of the artificial fracture is established; according to the experimental relational expression of the effective normal stress and the effective shear displacement, the relational expression of the natural fracture closing opening degree is obtained; and solving the mechanical equilibrium equation, the fracture closing critical opening criterion, the expression of the artificial fracture closing opening and the relational expression of the natural fracture closing opening to obtain the opening distribu