Study On Structural Topology Optimization Method And Its Application On Jacket Structure Of Offshore Wind Turbine

Attributable to the industrial development and global population growth with passing to the time,there is an uprising call for energy.Such demand can only be fulfilled using renewable energy resources.In existing sources wind energy is one of them along significant development all over the world.Comprehensive research is organized to make more efficient as well as to minimize the cost of wind energy.As on-shore and off-shore wind energy became more popular,more businesses began to investigate a novel optimal design in terms of minimize compliance and efficiency of wind turbine jacket structure.A wide range of topology optimization approaches,including mesh-independent convergence and several other approaches,have been widely used.However,these approaches generate gray transition zones,which are not a suitable state for any material.The purpose of this thesis is to determine the ideal structural design that minimize the compliance of the wind turbine jacket structure in order to reduce the deformation and maximizes efficiency.This is done to account for the dynamic loads that the wind turbine may face.In addition,since topology optimization has the potential to provide unique solutions to engineering design difficulties in a computational environment,while improving manufacturing efficiency and lowering costs.The traditional topology optimization algorithm is mostly suffered with the premature convergence and trapped into the local problems.This study provides a comprehensive overview of available topology optimization strategies for wind turbine jacket structure.An in-depth examination of solid isotropic material with penalization(SIMP)approaches was first provided,incorporating optimum criteria and filter sensitivity.Following that,a comparison of the advantages and pitfalls of the most recent optimization approaches,such as evolutionary structural optimization(ESO)and bidirectional evolutionary structural optimization(BESO),are introduced.It is proposed that a new function be employed in combination with a modified topology optimization technique.The Heaviside Projection Method(HPM)is used to optimize continuum topology in the proposed system.This approach is useful for determining the void and solid phases’ minimal length scale impact.The proposed approach is put into practice in order to acquire the minimum compliance for macrostructure.Moreover,two well-known projection and modified density-based optimization methodologies are merged into a single formulation process.This approach incorporates an impactful explicit geometric entity defined by shape variables that provides easy control in desired specific regions,implicit density-based topological optimization entities that use topological variables to provide crucial design elsewhere.The structural assemblies are the most appealing essential element of this combined formulation technique,and they are the most important part of it.Structures are often manufactured in multiple patches and joined together using structural assembly such as welding,riveting,and other methods.Putting structural patches in place at the desired location while without taking into consideration their dimension.This suggested method reveals the ability to set constraints on the geometry and topological characteristics of interfaces between specified patches.Additionally,a novel approach for geometric topology optimization problems has been proposed.The goal of this method is to minimize the volume fraction while taking into account numerous nodal displacement limitations.Maximum deflection is commonly exercised in practical engineering to estimate system stiffness.However,it is not commonly employed as an optimization constraint in geometrically topology optimization problems due to its complexity.It is proposed as a single constraint in this research that the maximum nodal displacement be met.To effectively address a large number of local displacement restrictions put on nodes in the user-specified zone,the p-mean aggregation function is being used.The objective and constraint functions’sensitivity to relative densities are computed.Through numerical examples,the influence of the aggregate parameter on the final design is studied further.Usual,compared to final designs from the traditional formulation,i.e.,minimization of end compliance with the volume fraction constraint or minimization of total volume regards to multiple nodal displacement constraints,the optimized findings strongly suggest the need for and efficiency of the current approach.Numerical examples represent the feasibility of the proposed method.The optimization results are compared and analyzed with the conventional topology optimization results.The comparison reveals that the optimization outcomes are affected by the aggregate parameters and the suggested approaches have the advantages of robustness and efficiency.It was noted that the ideal design may reduce compliance and the smallest number of iterations via numerical simulation,minimizing computing cost without sacrificing final construction correctness.