Optimization design method for sagging problem of car door based on CAE (Computer Aided Engineering) structural analysis

The invention discloses an optimization design method for the sagging problem of a car door based on CAE structural analysis, which comprises the steps of: obtaining a design input condition from total arrangement and configuration of a car body; creating a CAD (Computer Aided Design) model by modeling software; dividing grids of the CAD model; simulating actual conditions to create a connection relationship; simulating a boundary constraint condition during an actual test of a car door assembly; carrying out solution analysis on a finite element model generated finally; comparing a result obtained by finite element simulation operation with an industry standard; if an obtained conclusion is lower than the industry standard, providing a structural optimization design; and if the obtained conclusion is higher than the industry standard, completing final design output. The method not only enhances the inspection accuracy, but also greatly reduces the period of a whole repair part so as to shorten the time of developing the whole car. Structural errors can be corrected in time by CAE analysis in early design, thereby reducing the cost of developing the whole car.