Fluid-Structure Interaction Characterization in Serpentine Exhaust Nozzles

In order to explore the fluid-structure interaction (FSI) characteristics of serpentine nozzle, a numerical simulation framework of FSI for serpentine nozzle was constructed, and the changes of flow field characteristics and structural deformation in the nozzle under different pressure ratio states were studied. It is found that the complex geometry of the serpentine nozzle leads to the uneven distribution of internal flow parameters, and the structural deformation of the nozzle affects the internal aerodynamic load distribution of the nozzle. Under the action of the aerodynamic load of drastic changes in non-uniform flow, the nozzle is deformed, and the main deformation form is bulging from the inside to the outside, which further leads to the weakening of the expansion degree of flow in the nozzle and the increase of pressure. With the gradual increase of the inlet pressure ratio, the maximum deformation also increases, and the maximum deformation is about 2.9 mm, reaching 5% of the outlet height of the nozzle.