具有动态预置缓冲特性功能的磁流变胶泥缓冲装置原理及其冲击隔离性能研究

This project aims to solve the problem regarding deteriorated control performance of magneto-rheological fluid bumper (MRFB) due to sedimentation issue of conventional magneto-rheological fluids after long-term standing, and the difficulty of obtain anticipated bumpering behaviors by real-time control resulting from response delay of MRFBs during a crash process. magneto-rheological elasticity cement (MREC) is to be used as the control medium to fix the sedimentation issue of MR fluids. A novel mode of combining grading crushing and magnetron throttle is to be studied for a MREC bumper so as to increase the energy absorption capacity. Pre-loaded transient current is applied to produce an anticipated bumpering performances. Specifically, the energy absorption characteristics and design method of cascade crushing structures are to be studied. The jointly optimized model of dynamic magnetic circuit and impact flow based on multi-radial channels are to be built, and the parameters of magnetron throttle unit are to be optimized. Then, a MREC bumper based on the design above will be developed, along with the design of a transient current source. In order to verify the methodologies and the prototypes, drop tests are to be carried out and an impact dynamic model for the bumper will be established. The project will also focus on a pre-estimating methodology for the collision parameters based on radar detector array, as well as the estimation theory for current configuration parameters and the trigger time. At last, the technology evaluation specification will be studied. The innovations of the project are summarized as follows: MREC is used as the control medium to solve the sedimentation issue of conventional MR fluids; the difficulty of obtain anticipated bumpering behaviors by real-time control is solved by pre-estimating collision parameters and current configuration parameters together with applying pre-loaded current.

针对磁流变液长期静置沉降导致磁流变液缓冲装置存在控制特性劣化的问题和磁流变缓冲装置响应滞后导致难以通过实时控制获取期望缓冲特征的问题，项目以磁流变胶泥为控制介质，研究基于分级压溃与磁控节流共同作用模式的磁流变胶泥缓冲装置原理，采用提前施加瞬变励磁电流方法实现缓冲特性动态预置。研究串级压溃体缓冲吸能特性与设计方法，建立基于多级径向通道的动态磁路模型与冲击流动联合优化模型，优化磁控节流单元参数，研制出磁流变胶泥缓冲装置源样机；开展落锤冲击实验和建立冲击动力学模型，研究基于雷达探测器阵列的碰撞参数预估方法，电流形态参数估计理论和触发时刻估计理论，开展预置缓冲特性条件下的冲击实验与冲击隔离评价技术研究。创新之处：利用磁流变胶泥流变学特性可控和长期不沉降的特点，解决控制介质沉降问题；利用动态预估碰撞参数、预估电流形态参数和提前施加电流方法实现缓冲特性预置功能，解决实时控制难以实现期望缓冲特性问题。

针对传统磁流变液长期静置沉降导致磁流变液缓冲装置存在控制特性劣化的问题，传统压溃型缓冲装置和液压缓冲装置冲击力传递率不可控的问题，项目以磁流变胶泥为控制介质，开展基于分级波纹压溃与磁控节流耦合作用的磁流变胶泥缓冲装置设计原理与方法。研究了波纹压溃体缓冲吸能特性，建立了多级径向通道的动态磁路模型与冲击流动联合优化模型，优化了磁控节流结构参数和磁学参数，研制出了磁流变胶泥缓冲装置样机。以激光位移传感器和动态力传感器实时感知缓冲参数，制作了信号采集和数据处理仪器，利用落锤冲击试验机的构建了冲击试验平台，开展了多种冲击工况的落锤冲击实验，研究了碰撞参数预估控制方法。研究表明，以特定粘度的聚硅氧烷作为载体液，利用其剪切稀化效应和链状微观结构，可以实现1年静置沉降不超过5%的稳定性；以磁流变胶泥作为磁控介质，采用多级波纹压溃和多级径向节流的缓冲装置控制率可以达到30%以上；采用径向倾斜流道和中心泄流孔，实现冲击力控制率的有效途径。在项目执行过程中，研究团队发表期刊论文17篇，其中SCI收录8篇，EI收录9篇；参加国际电磁流变学学术会议2次，交流论文2篇，参加国内流变学学术会议2次，交流论文4篇；申报中国发明专利16项，其中授权5项；联合申报省部级科技进步奖1次，获准重庆市科技进步1等奖1项，项目负责人排名第二。项目培养博士研究生4名，硕士研究生7名。项目的研究意义在于：传统的压溃吸能缓冲装置和液压吸能缓冲装置冲击力传递特性不可控，难以满足不同冲击工况对冲击隔离的要求。为解决汽车碰撞吸能装置、武器发射制退缓冲装置、飞行器着陆缓冲装置和轨道车辆车厢之间缓冲装置等冲击力传递特性不可控的问题，提供了新的解决思路，奠定了理论和技术基础。