Research On Aeroelasticity Of A Large Fineness Ratio Flight Vehicle

Missiles and rockets for modern warfare are require to have better performance in some aspects such as high speed,high precision and long-range attack.The flight vehicle which has large fineness ratio does have great advantages.However,the enhancement of the fineness ratio of the rockets will reduce the rigidity of the rocket’s structure,which makes aeroelastic phenomenon easily occur during the flight.In this paper,the aeroelastic characteristics of a large fineness ratio flight vehicle is investigated to find out the relationship between the aeroelasticity and flight performance,which can provide references for the design of the rocket and its guidance control system,as well as the prediction of trajectoryFirstly,the aerodynamic characteristics of a large fineness ratio rocket are analyzed with CFD method.Commercial software FLUENT is employed to compute the flow field in a range of flight conditions to demonstrate how the drag coefficient,lift coefficient and pitching moment coefficient change with different Mach numbers and angles of attack.Secondly,fluid-structure tightly coupling method is employed to investigate the static aeroelastic characteristic of the large fineness ratio rocket.Fluid-structure interaction model is built on ANSYS Workbench to obtain the deformation of the rocket’s structure under the aerodynamic forces,the aerodynamic characteristics of the deformed rocket,and the effect of aeroelasticity on flight performance of the large fineness ratio flight vehicle.Finally,finite element method is used to analyze the flutter characteristics of the large fineness ratio flight vehicle.The flutter characteristics is described through v-g and v-f curves whose data is calculated in three different flight altitude with PK method.Aiming at the problem that flutter phenomenon appears around the operating speed,the rocket is reconstructed to improve its flight performance.