Network Study of Plant Leaf Topological Pattern and Mechanical Property and its Application

Abstract

In order to explore the compliance structure and adaptability of the vein pattern of plant leaf, five fresh and mature leaf samples, which represent the typical leaf network in nature, are collected, and the finite element model of the samples are established and simulated. The results show that the topological pattern of plant leaf is self-adaptive to the multi-load fields. When considering the change of wind loads, it is found that the main vein consistently remains unchanged, and the lateral vein changes slightly along different wind load direction. Inspired by the similar work environment and structure, the bionic methodology of wind turbine blade is developed in this paper. Firstly, the wind turbine blade structure is optimized by using SIMP method. The results indicate that material distribution of wind turbine blade is similar to the leaf vein, where, the spar cap of the blade is equivalent to the main vein of leaf, and the skins are correspond to the lateral vein of leaf. Secondly, considering the similar stress environment, such as random wind loads, rain, snow, and self-weight, the topology structure of wind turbine blade was decided by referring the natural structure. Finally, the bionic method is used to design the spar cap region of the blade. The results show that the best fatigue life appears in blades with the ply angle in the range between 45° and 65°. It is not only coincident with the side vein angle of most plant leaves, but efficiently improves the blade fatigue performance.Keywords: Plant Leaf; Medial Axis; Self-Adaptability; Wind Turbine Blade; Bionic Design