Topology Optimization Of Skeleton Structure Of Airship

Lightweight is one of the core issues for airship structural design, however, it is aneffective way for airship lightweight using optimization. Structural optimization can bedivided into three levels, which are shape optimization, topology optimization andcross-section optimization. Among them, shape optimization and cross-sectionoptimization belongs continuous variable optimization problem, related method is moremature. But topology optimization of discrete variable optimization problem is morecomplex, previous studies main against the two-dimensional truss structures, and forcomplex spatial truss structures, related method is still in the exploratory stage. In thisarticle, CFRP pipe truss is as research subjects, which is triangular cross-section formairship skeleton. First, introduction of genetic algorithms and parameter sensitivityanalysis methods, it Solve the typical CFRP tube truss segment topology optimizationproblem. Based on that, the objective of lightening the airship structure was achievedand the topology optimization of complex spatial truss system was resolved by means ofclarifying the typical CFRP pipe truss components and splitting and combining theoverall structure. Including the following aspects mainly:1. Based on genetic algorithm combined with MATLAB programming and ANSYSsoftware secondary development, a topology optimization method had been established,which applied to triangular cross-section truss structure of CFRP tube. Geneticalgorithms had many issues, such as the slow convergence, Local optimization abilitydifference, premature, poor mobility, it proposed encoding method as the basic unit withtruss section, to replace a unit with bar traditional, in this way, the optimization hadbetter convergence and stability. Finally, the optimization had been validatedcorrectness and effectiveness with some examples.2. Parameter sensitivity analysis was introduced into topology optimization forspace truss. Parameter sensitivity analysis before topology optimization of space truss, itascertained optimize parameter and Range of values for the parameter. Topologyoptimization of space trusses for moment and torsional received satisfactoryoptimization results with optimization objective of minimum product for strain energyand mass, considered constraints liking strength of materials, buckling load of member,detailing requirements. 3. Ellipsoidal airship skeleton structure was designed with size220m360m360m,then stress nature analysis for airship skeleton structure. The results showed that thetruss in airship skeleton structure subjected stretch bending or Press bending mainly.Classification indicators for stress state had been established, by integrated bendingmoment and axial force with three control sections in the truss ends and span. Extractedtypical truss from airship skeleton structure lain the foundation for airship skeletonoptimization.4. The split-combine topology optimization approach for sophisticated spatial trussstructures was introduced in the refinement of an airship structure. During the splittingphase, a MATLAB optimization program was conducted in the topology optimizationanalysis of the thorough typical trusses, followed by the assembly procedure of therefined trusses.