To increase the robustness of the optimization solutions of the mixed-flow pump,the impeller was firstly indirectly parameterized based on the 2D blade design theory.Secondly,the robustness of the optimization solutio...To increase the robustness of the optimization solutions of the mixed-flow pump,the impeller was firstly indirectly parameterized based on the 2D blade design theory.Secondly,the robustness of the optimization solution was mathematically defined,and then calculated by Monte Carlo sampling method.Thirdly,the optimization on the mixed-flow pump′s impeller was decomposed into the optimal and robust sub-optimization problems,to maximize the pump head and efficiency and minimize the fluctuation degree of them under varying working conditions at the same time.Fourthly,using response surface model,a surrogate model was established between the optimization objectives and control variables of the shape of the impeller.Finally,based on a multi-objective genetic optimization algorithm,a two-loop iterative optimization process was designed to find the optimal solution with good robustness.Comparing the original and optimized pump,it is found that the internal flow field of the optimized pump has been improved under various operating conditions,the hydraulic performance has been improved consequently,and the range of high efficient zone has also been widened.Besides,with the changing of working conditions,the change trend of the hydraulic performance of the optimized pump becomes gentler,the flow field distribution is more uniform,and the influence degree of the varia-tion of working conditions decreases,and the operating stability of the pump is improved.It is concluded that the robust optimization method proposed in this paper is a reasonable way to optimize the mixed-flow pump,and provides references for optimization problems of other fluid machinery.展开更多
为了提高涡轮冷却叶片的结构设计效率,采用UG OPEN API与特征参数相结合的方法,建立涡轮叶片典型冷却结构的参数化设计模型。通过定义壁厚、隔板特征参数实现内外型的参数化设计,基于此模型,通过定义气膜孔、扰流肋、劈缝、扰流柱、旋...为了提高涡轮冷却叶片的结构设计效率,采用UG OPEN API与特征参数相结合的方法,建立涡轮叶片典型冷却结构的参数化设计模型。通过定义壁厚、隔板特征参数实现内外型的参数化设计,基于此模型,通过定义气膜孔、扰流肋、劈缝、扰流柱、旋流冷却结构的特征参数进行编程输出特征形状的点坐标和方向等参数。通过UG OPEN API实现特征结构的快速三维建模。设计人员通过参数修改,即可快速地进行三维建模,提高了设计效率,大大缩短了结构设计周期。展开更多
为进一步扩大电动汽车乘员空间并提升其安全性能,车身电池一体化技术(cell to body,CTB)将电池作为结构件集成到车身底部,不仅有效减少车身零件及连接数量,且有助于实现新能源汽车的轻量化及增加续航里程。针对CTB结构可能带来的碰撞安...为进一步扩大电动汽车乘员空间并提升其安全性能,车身电池一体化技术(cell to body,CTB)将电池作为结构件集成到车身底部,不仅有效减少车身零件及连接数量,且有助于实现新能源汽车的轻量化及增加续航里程。针对CTB结构可能带来的碰撞安全问题和传力路径中断风险,本文提出了一套基于CTB结构的车身正面碰撞安全设计流程。采用“传力分解-仿真分析-试验对标”的设计方法,首先确保电池在正面碰撞中的安全性,然后设计多级传力路径以优化车身结构,并根据碰撞力值规划设计车身前部结构。通过有限元仿真分析及试验测试,验证了该方法的可行性,为未来的车身设计及应用提供了一种有效的设计方法及思路。展开更多
基金National Natural Science Foundation of China(51609107)Open Subject of Provincial and Ministerial Discipline Platform of Xihua University(szjj2018-123)。
文摘To increase the robustness of the optimization solutions of the mixed-flow pump,the impeller was firstly indirectly parameterized based on the 2D blade design theory.Secondly,the robustness of the optimization solution was mathematically defined,and then calculated by Monte Carlo sampling method.Thirdly,the optimization on the mixed-flow pump′s impeller was decomposed into the optimal and robust sub-optimization problems,to maximize the pump head and efficiency and minimize the fluctuation degree of them under varying working conditions at the same time.Fourthly,using response surface model,a surrogate model was established between the optimization objectives and control variables of the shape of the impeller.Finally,based on a multi-objective genetic optimization algorithm,a two-loop iterative optimization process was designed to find the optimal solution with good robustness.Comparing the original and optimized pump,it is found that the internal flow field of the optimized pump has been improved under various operating conditions,the hydraulic performance has been improved consequently,and the range of high efficient zone has also been widened.Besides,with the changing of working conditions,the change trend of the hydraulic performance of the optimized pump becomes gentler,the flow field distribution is more uniform,and the influence degree of the varia-tion of working conditions decreases,and the operating stability of the pump is improved.It is concluded that the robust optimization method proposed in this paper is a reasonable way to optimize the mixed-flow pump,and provides references for optimization problems of other fluid machinery.
文摘为了提高涡轮冷却叶片的结构设计效率,采用UG OPEN API与特征参数相结合的方法,建立涡轮叶片典型冷却结构的参数化设计模型。通过定义壁厚、隔板特征参数实现内外型的参数化设计,基于此模型,通过定义气膜孔、扰流肋、劈缝、扰流柱、旋流冷却结构的特征参数进行编程输出特征形状的点坐标和方向等参数。通过UG OPEN API实现特征结构的快速三维建模。设计人员通过参数修改,即可快速地进行三维建模,提高了设计效率,大大缩短了结构设计周期。
文摘为进一步扩大电动汽车乘员空间并提升其安全性能,车身电池一体化技术(cell to body,CTB)将电池作为结构件集成到车身底部,不仅有效减少车身零件及连接数量,且有助于实现新能源汽车的轻量化及增加续航里程。针对CTB结构可能带来的碰撞安全问题和传力路径中断风险,本文提出了一套基于CTB结构的车身正面碰撞安全设计流程。采用“传力分解-仿真分析-试验对标”的设计方法,首先确保电池在正面碰撞中的安全性,然后设计多级传力路径以优化车身结构,并根据碰撞力值规划设计车身前部结构。通过有限元仿真分析及试验测试,验证了该方法的可行性,为未来的车身设计及应用提供了一种有效的设计方法及思路。
