Fully adaptive isogeometric topology optimization using MMC based on truncated hierarchical B-splines

In the present work, we introduce a fully adaptive isogeometric topology optimization using moving morphable components through truncated hierarchical B-splines (THITO-MMC), where the hierarchical computational mesh of adaptive isogeometric analysis method is locally refined and coarsened simultaneously during topology optimization. The complete adaptivity of the hierarchical mesh and the associated hierarchical function space is achieved by a fully adaptive mark strategy. We successfully apply THITO-MMC method to two-dimensional and three-dimensional topology optimization problems of maximizing structural stiffness, with or without taking different values of reactivating parameter into consideration. Numerical results show that THITO-MMC delivers an effective MMC-based topology optimization method for what concerns not only the convergence rate of topology optimization but also the computational efficiency without deteriorating the optimized structural stiffness. The comparison with adaptive isogeometric topology optimization with only hierarchical local refinement considered demonstrates that our fully adaptive scheme returns identical optimized results while strongly improving convergence rate and decreasing computational burden involved in obtaining displacement field.