Suction structure for improving flow field quality of plane cascade wind tunnel and design method thereof

The invention belongs to the technical field of subsonic plane cascade wind tunnel tests, and particularly relates to a suction structure for improving the flow field quality of a plane cascade wind tunnel and a design method of the suction structure. The suction structure comprises a wind tunnel upper wall (1), a wind tunnel lower wall (2) and a test piece (3) arranged between the wind tunnel upper wall (1) and the wind tunnel lower wall (2), a through inclined channel is formed in the wind tunnel upper wall (1), and a preset distance L exists between the center of the inclined channel and the front edge of a first blade, close to the wind tunnel upper wall (1), of the test piece (3). According to the suction structure for improving the quality of the plane cascade wind tunnel flow field, when a wind tunnel test is carried out, a low-speed area is obviously improved, airflow angle deviation is also corrected, the quality of the flow field in front of the cascade meets the test requirement, and the accuracy o