模具冷却通道截面拓扑优化设计

本文提出一种模具冷却通道截面设计的拓扑优化方法。根据直通道的特性建立等效的温度场模型,用均匀流体速度场代替湍流流速场,构建对流换热方程,并用第三类边界条件对流道入口温度边界进行描述。建立考虑热应力的热-力耦合模型,对模具结构的热机械性能进行描述。通过引入离散体过滤法得到含圆形通道的截面拓扑,并加入几何约束解决离散体法导致的相混问题。分别以模具表面的平均温度和位移均匀性为优化目标及约束条件,构建拓扑优化列式。通过平顶模具与U型模具设计实例,验证了本文方法的可行性。设计结果表明,本文方法能够得到清晰的拓扑结构,而且优化结果满足给定的管径、管间距及管到模面距离等尺寸约束。

Topology optimization of the cross-section layout of channel-cooling tools

A topology optimization method is proposed for design of the layout of channel-cooling tools.An equivalent convective heat transfer model is established considering the characteristic of straight cooling channels.A uniform velocity field is used to mimic the turbulent flow field.The temperature boundary condition on the channel inlet is described by a Robin type boundary condition.A thermo-elastic model is established to describe the thermo-mechanical behavior.A discrete object filter is introduced to get circular topology.A geometric constraint is introduced to solve the mixed-phase problem caused by the filter.The mean temperature and the displacement field uniformity are set as an objective function and a constraint,respectively.A flat top design and a U-shape tool design are optimised to show the feasibility of the present method.Optimized design results show that a clear topology can be achieved.Furthermore the optimized topology satisfies the geometric requirements of the channel radius,the distance between channels and the minimum distance between channels and the tool surface.