| Structure optimization has been developed gradually and applied for product design. Structure optimization technology holds the position of play a decisive role in the design and development of automobile products. It can acquire the best distribution of material while maintaining or improving the structure and properties of materials, and it makes the complicated structures being neatly and reasoningly selected in concept design stage.In this thesis the author takes some of10m3mixer as the research object. Based on the finite element analysis theory, it finds that torsion condition is dangerous conditions based on the frame in bending and torsion analysis. The maximum equivalent stress of the mixer frame is very close to the material allowable stress under the torsion condition. In order to reduce the maximum equivalent stress on the frame under the torsion condition, topology optimization model is established according to the actual size of the original mixer frame structure. Its topology optimization design is completed based on SIMP(Solid Isotropic Microstructures with Penalization), which takes the compliance of several load steps as the objective function, and the volumefrac as the constraint function. The new frame structure extracted from the result of topology optimization with technological and economic requirements. Then take some of the new frame as the research object, its size optimization design takes the minimum quality as the objective function.The constraint function has two parts. One is its maximum equivalent stress has to lower than200MPa under the torsion condition, another one is that its step one modal frequency has to higher than20Hz.Compare to the original frame,the new frame’s quality has dropped about7.8percent. According to the static and dynamic analysis of the optimized frame, we find that the maximum equivalent stress on the frame under the torsion and bending condition has dropped compare to the original frame. It also successfully avoid the road excitation, achieved the purpose of topology optimization and size optimization. |
