Abstract: A self-adapted stiffening layout design of plate and shell structure is proposed by imitating the distribution form and growth characteristics of the veins of dicotyledonous plants in nature. By bionic design, the process of stiffening the structure can be seen as a branching structure growing step by step. From the given seed point position, growth and branching are carried out along the direction that makes the structural performance optimal. Meanwhile, the reinforcement that contribute least to the structural performance are degraded to gradually form the optimal stiffened layout. Taking the rectangular thin plate as an example, firstly, by using the stiffness optimization of typical examples can verify the method. Then, combining the finite element analysis method and acoustic radiation mode method, the radiated acoustic power of the structure is obtained and the acoustic power sensitivity under the bionic venation growth law is calculated. Based on the sensitivity distribution of sound power and "element birth and death", the reinforcement layout can be realized, and the scheme of structure reinforcement layout with the lowest radiation sound power is finally found. Finally, investigating the influence of excitation frequency on reinforcement layout. The results show that the optimal layout of reinforcement obtained by the bionic venation optimization method is more effective than the existing traditional methods, with clearer layout and better results. The correlation analysis can provide scientific guidance for the reinforcement layout optimization design of light-weight plate shell structure.

Key words: bionics design, stiffeners for thin plate, topology optimization, sound radiation, sensitivity analysis