In order to solve the problems that in the prior art, calculation precision and efficiency are difficult to consider at the same time during supersonic jet
machining, and detached shock
waves cannot be accurately captured, the invention provides a
finite element simulation method for the stagnation flexible constraint flow field characteristics of a jet
impact area. The
finite element simulation method comprises the steps that firstly, a geometric model of a jet area and an outer
watershed is established, and preliminary solving is conducted; extracting
jet flow axis pressure gradient characteristics to determine detached
shock wave interval coordinates; then reconstructing a block geometric model comprising an upper
jet flow region, a detached
shock wave region, a stagnation region and an outer
watershed according to the coordinates, and implementing differential local grid
encryption on the
shock wave region and the stagnation region; and finally, carrying out second iterative solution based on the Sutherland
viscosity law to obtain final flow field distribution. According to the method, the thickness and the position of the shock wave layer are accurately captured while the number of the grids is controlled through the block
encryption strategy, the contradiction between the calculation economy and the
numerical precision under the
transonic flow condition is solved, and the method is suitable for numerical
simulation of the complex supersonic gas
jet flow field containing the detached shock wave and the stagnation region.