Optimaldesignand Mechanical Analysis Of The Variable Sweep Wings Structure

The study of morphing aircraft has become the top hot content of the developmentof today’s aviation industry. The most common morphing are the variable-camber wing,folding wing, torsion wing and the variable sweep wing. Among these, the variablesweep wing belongs to an important research field in the study of morphing aircraft.And the optimization of the location and the amount in the variable sweep wingstructure are extremely important. To optimize the location of actuator can make themorphing wing drive better, improve the utilization factor of the actuator，and reducethe energy loss. This paper’s another part focus on the difference of variable sweepwing’s aerodynamic characteristics in different status，in order to make a betterknowledge and understanding of the advantages and disadvantages before the morphingof variable sweep wing and after。The optimal location of actuator within an cell morphing mechanism can make theactuator realize the movement of morphing structure under less driving force, improvethe drive efficiency of the actuator. To use the fmincon function in Matlab OptimizationToolbox to solve the objective function. And use the quasi-static analysis method toestablish the equilibrium equations during the cell structure’s morphing process whichbased on the principle of virtual work equations. This equation contains the parameterZ1of the actuator location which needs to be optimized, and the another actuatorlocation in the cell Z2will be calculated by the law of cosine.About the choice the actuator amount in multi-cell of morphing structure and itslayout scheme, it will use static analysis to make it come true. The finite elementsoftware Abaqus/CAE is used to make a static analysis on different layout scheme ofmulti-cell morphing structure, to place on aerodynamic loading to the actuator’s plane.When the output of the maximum stress and its location in the morphing structure comeout, so does the output of the maximum morphing of the wing tip. From the results ofthe analysis, it will gain a better actuator layout scheme in multi-cell morphing structurewith both better strength and stiffness.This paper makes a comprehensive analysis of morphing structure in differentstatus, different angles of attack and different Mach number. Using the CFD softwareFLUENT to develop numerical simulation during the whole morphing process ofmorphing structure in different conditions, and obtain the aerodynamic characteristic indifferent status. From the calculate results, it can be seen that if flying with low speed,larger aspect ratio can gain more lift; if flying in fast speed, smaller aspect ratio cangreatly reduce drag; if the Mach number is lower, the Mach number’s change influences lift,drag and lift-drag ratio little.