Reconstruction Algorithm Of Plant Tissue And Palm Petiole-Inspired Bionic Design Of Honeycomb Structure

The good adaptive relationship between the multi-scale structure of natural plants and its mechanical properties provides inspiration for bionic engineering design.The tissue reconstruction and mechanical property calculation in the meso-scale are an important link to achieve multi-scale bionic design.In view of the shortcomings of existing plant tissue reconstruction algorithms,this paper proposes a distance weighted reconstruction algorithm based on virtual segmentation.Meanwhile,the king palm petiole structure was selected as the research object.Through the multi-scale structural modeling,the structural characteristics and mechanical properties of the vascular bundles in the petiole are analyzed,and the relationship between the multi-scale structure and its mechanical properties is explored.Subsequently,its structural features are applied to the structural design of the honeycomb sandwich panel to improve the bending and torsion resistance.Finally,based on the similarity of the stress environment and configuration of the king palm and the wind turbine blade,the bionic honeycomb panel structure is applied to the web structure design of the wind turbine blade to improve the bending and torsional load carrying capacity of the blade structure.The main research contents of this paper are as follows:(1)The development of plant tissue reconstruction algorithmIn order to accurately reconstruct the elongated cels and concave structures in natural plants,the Delaunay triangulation based on virtual segmentation optimization is proposed in this paper.The area weighted tesselation(AWT)algorithm is applied to structures with excessive cell size differences.Based on the distance weighted tesselation(DWT)algorithm,the effective reconstruction of this kind of structure is realized.A finite boundary recognition and reconstruction method is proposed.The boundary reconstruction effect can be achieved for different types of boundary organizations.Thus,a high-precision reconstruction algorithm with a wide range of applications-ODWT,is obtained.Compared with the Centroid-based Voronoi tesselation(CVT)and area weighted tesselation(AWT),the ODWT algorithm has obvious advantages.(2)Influence of reconstruction algorithm on prediction accuracy of multi-scale mechanical properties modelingThe CVT algorithm and the ODWT reconstruction algorithm proposed in this paper are used to reconstruct the vascular bundle tissue of the king palm petiole,and the cell wall of the vascular bundle tissue is equivalent to a multi-layer laminate.The layered plate model with the intermediate layer is used to train the vascular bundle structure modeling.The finite element method is used to simulate the anisotropic tensile modulus of vascular bundle elements,and the simulation prediction values of CVT algorithm and ODWT algorithm reconstruction model are compared.The influence of reconstruction model on multi-scale modeling mechanical properties prediction accuracy is analyzed.Finally,the tensile test of petiole tissue was carried out and the variation of mechanical properties of petiole tissue under different water content was studied.The results of finite element simulation were compared to verify the accuracy of ODWT reconstruction model.(3)Gradient change of microscopic parameters of vascular bundles in king palm petiole and its effect on mechanical properties of petioleAccording to the gradient change of the petiole structure of the king palm,the cross section is divided into three regions,and samples are collected in three regions.The longitudinal tensile properties of these three regions were tested by a single vascular bundle tensile test,and the influence of the cross-sectional area of the vascular bundle on its elastic modulus was studied.The mechanical model of three different regional vascular bundle elements was established by multi-scale modeling method and the difference of the elastic modulus of vascular bundles in different regions and the influence of microstructure parameters on the mechanical properties of vascular bundles were analyzed.The petiole segmentation model was established according to the actual size of the petiole,and the influence of the gradient stiffness distribution on its bending torsion performance was simulated.(4)Structural parameter design of gradient honeycomb panel and its application in wind turbine blade web structureBased on the structural characteristics of the king palm petiole,the parameters of the honeycomb sandwich panel were designed by using the thickness gradient distribution.Two kinds of gradient honeycomb panels were obtained: linear gradient honeycomb panel and proportional gradient honeycomb panel,and their torsion and bending stiffness were simulated and tested.The analysis is carried out and finaly applied to the web design of the wind turbine blade.Through the three-point bending and bending-torsional coupling simulation,it is found that the thickness gradient distribution can improve the bending stiffness and torsional stiffness of the blade and make the stress distribution more uniform.