Three-duct retractable tail nozzle structure

The utility model provides a three-duct convergent-divergent type tail nozzle structure which comprises a tail cone, a lobe mixer, an inner nozzle, an outer nozzle and a nacelle rear end shell, the outer nozzle is arranged in the nacelle rear end shell, and the inner nozzle is arranged in the outer nozzle. The mixed flow of the core flow and the secondary flow is expanded in the inner spray pipe,the third flow is expanded in the third flow channel between the inner spray pipe and the outer spray pipe, and the speed difference of the two jet flows is small and is basically the same as the speed of the surrounding atmosphere flowing through the shell at the rear end of the nacelle; therefore, the problem that the aerodynamic performance and noise performance of the supersonic passenger plane are deteriorated due to insufficient expansion of the spray pipe under transonic and supersonic working conditions in the prior art is solved. 一种三涵道的收扩型尾喷管结构，包括尾锥、波瓣混合器、内喷管、外喷管以及短舱后端外壳，短舱后端外壳的内部设置外喷管，外喷管的内部设置内喷管，应用本实用新型提供的发