磁流变液仿生薄壁吸能管及其耐撞性可控度的研究

Study on Magnetorheological-fluid Bio-inspired Thin-walled Energy-absorbing Tube and Its Crashworthiness Controllability

为克服传统薄壁管耐撞性恒定、环境适应性差的缺点,受马尾草结构的启发,提出一种可应用于薄壁管结构设计的磁流变仿生吸能单元的设想。建立了磁流变液仿生单元吸能理论模型和吸能可控度理论公式,对一定尺寸的磁流变液仿生单元进行了有限元仿真分析。结果显示:在一定尺寸和一定压缩条件下,流固耦合仿真和固体结构仿真预测的磁流变液和固体结构的吸能与理论模型预测结果相差分别仅为3.49%和2.16%,磁流变仿生单元吸能可控度随压缩长度的增加而减小,最高可达27.73%。在压缩近67%的长度下,可控度仍可达到12.29%,仿真预测的可控度值与理论值高度一致。最后,将仿真中一定尺寸的磁流变仿生吸能单元应用于传统9胞薄壁管中。对比结果表明:与传统9胞薄壁管结构相比,填充了磁流变仿生吸能单元的薄壁管总吸能量提高了293.7%,固体结构的比吸能提高了62.54%,最大可控度达22.44%。

In order to overcome the traditional thin-walled tubes’shortcomings of constant crashworthiness and poor environmental adaptability,a conception of magnetorheological bionic energy-absorbing element(MBEE)is proposed,which is inspired by the structure of horsetailand can be applied to the design of thin-walled tube.The theoretical modelfor the energy-absorption of magnetorheological bionicelement and the theoretical formulae of energy absorbing controllability are established and a simulation is conducted on the MBEE with certain size.The results show that in the condition of certain size and compression,the differences of the energy-absorption amount of magnetorheological fluid and solid structure predicted by fluid-solid coupling and solid structure simulations and theoretical values are 3.49%and 2.16%respectively.The energy absorbingcontrollability of MBEEreduces with the increase of compressed length,which can be as high as 27.73%at most and can still be 12.29%at 67%of compressed length.The controllability value predicted by simulationis highly consistent with theoretical value.Finally,the MBEE with certain size is filled into the traditional 9-cell thin-walled tubefor simulation with a result indicating that compared with 9-cell thin-walled tube,the total energy-absorption amount of the thin-walled tube filled with MBEE increases by 293.7%,andthe specific energy absorption of solid structure rises by 62.54%with the maximum controllability reaching 22.44%.