考虑疲劳性能的驾驶室拓扑优化设计

Cab Topology Optimization Design Considering Fatigue Performance

针对某重型货车驾驶室台架疲劳试验出现破坏问题,提出了以疲劳寿命最大化为目标的双向渐进结构优化方法(FA-BESO)。首先,进行驾驶室的台架试验,找到驾驶室疲劳薄弱位置。进一步推导单元低周疲劳分析的灵敏度,以此值作为单元删减依据,通过对有限元软件进行二次开发来实现连续体结构的FA-BESO。接着,通过标准算例验证了此方法的有效性。最后,为提高优化效率,建立驾驶室的梁骨架简化模型,并验证了简化模型对于疲劳破坏位置具有良好预测性,将该算法运用到A柱加强板的考虑疲劳性能的拓扑优化中,优化结果表明,驾驶室的疲劳寿命可比优化前提高2倍,验证了FA-BESO提高驾驶室疲劳寿命的可行性。

For the failure of the cab of a heavy truck during the fatigue test on the bench,a bi-directional evolutionary structural optimization method(FA-BESO)aiming at maximizing the fatigue life is proposed in this paper.Firstly,the bench test of the cab is carried out to find the weak position of the cab fatigue.Furthermore,the sensitivity of the element low-cycle fatigue analysis is deduced,and this value is utilized as the basis for element deletion.The FA-BESO of the continuum structure is realized through the secondary development of the finite element software.Then,the effectiveness of FA-BESO is verified by a standard example.Finally,in order to improve the optimization efficiency,a simplified model of the beam frame for the cab is established,and it is verified that the simplified model has good predictability for the fatigue failure position.The FA-BESO is applied to the topology optimization of the A-pillar reinforcement plate considering fatigue performance,and the result shows that the fatigue life of the cab can be increased to 2 times compared with that before optimization,which verifies the feasibility of the FA-BESO to improve the fatigue life of the cab.