Method and system for determining marine riser suspension mode operation window

The invention discloses a method for determining a marine riser suspension mode operation window, which comprises the following steps of: according to an operation working condition range, equidistantly dividing ocean current flow velocity in p/2 and effective wave height in q/2 to obtain a working condition matrix consisting of the ocean current flow velocity and the effective wave height, and carrying out region block division on the working condition matrix to obtain p * q working condition groups; searching an operation limit working condition from the first working condition group, and selecting four working condition calculation points in the working condition groups to perform dynamic solution calculation of the marine riser in the suspension mode; key index data of the marine riser are extracted and compared with the limit criterion of the marine riser operation window, and a new working condition set (i ', j') is determined based on a three-point judgment method; the second step and the third step ar