To improve the design speed and reduce the design cost for the previous blade design method, a modified inverse design method is presented. In the new method, after a series of physical and mathematical simplification...To improve the design speed and reduce the design cost for the previous blade design method, a modified inverse design method is presented. In the new method, after a series of physical and mathematical simplifications, a sail?like constrained area is proposed, which can be used to configure di erent runner blade shapes. Then, the new method is applied to redesign and optimize the runner blade of the scale core component of the 1400?MW canned nuclear coolant pump in an established multi?optimization system compromising the Computational Fluid Dynamics(CFD) analysis, the Response Surface Methodology(RSM) and the Non?dominated Sorting Genetic Algorithm?II(NSGA?II). After the execution of the optimization procedure, three optimal samples were ultimately obtained. Then, through comparative analysis using the target runner blade, it was found that the maximum e ciency improvement reached 1.6%, while the head improvement was about 10%. Overall, a promising runner blade inverse design method which will benefit the hydraulic design of the mixed?flow pump has been proposed.展开更多
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
为了改善离心压气机叶片多工况优化设计时面临的设计空间大、冗余搜索、灵活性不足、优化效率低等问题,提出了基于自由曲面变形技术(free form deform,FFD)的离心压气机复杂曲面叶片参数化方法,建立了叶片局部几何区域与三维空间网格控...为了改善离心压气机叶片多工况优化设计时面临的设计空间大、冗余搜索、灵活性不足、优化效率低等问题,提出了基于自由曲面变形技术(free form deform,FFD)的离心压气机复杂曲面叶片参数化方法,建立了叶片局部几何区域与三维空间网格控制体的映射模型,研究了样条曲线基函数几何特性对叶片几何构型的影响,实现了离心压气机叶片几何外形的局部精细化改型.结合B样条基FFD参数化方法、多目标进化算法和计算流体动力学对复杂叶片的局部区域进行了多工况气动寻优,优化结果表明:在满足约束条件的情况下,流场结构得到进一步的改善,额定工况和常用工况等熵效率分别提高了0.48%和0.40%,喘振裕度分别提升了1.6%和1.8%,利用较少的设计变量实现了离心压气机复杂曲面叶片高效灵活的精细化设计,为离心叶轮的气动优化设计提供了新的理论依据.展开更多
基金National Basic Research Program of China(973 Program,Grant No.2015CB057301)Research and Innovation in Science and Technology Major Project of Liaoning Province,China(Grant No.201410001)Collaborative Innovation Center of Major Machine Manufacturing in Liaoning Province,China
文摘To improve the design speed and reduce the design cost for the previous blade design method, a modified inverse design method is presented. In the new method, after a series of physical and mathematical simplifications, a sail?like constrained area is proposed, which can be used to configure di erent runner blade shapes. Then, the new method is applied to redesign and optimize the runner blade of the scale core component of the 1400?MW canned nuclear coolant pump in an established multi?optimization system compromising the Computational Fluid Dynamics(CFD) analysis, the Response Surface Methodology(RSM) and the Non?dominated Sorting Genetic Algorithm?II(NSGA?II). After the execution of the optimization procedure, three optimal samples were ultimately obtained. Then, through comparative analysis using the target runner blade, it was found that the maximum e ciency improvement reached 1.6%, while the head improvement was about 10%. Overall, a promising runner blade inverse design method which will benefit the hydraulic design of the mixed?flow pump has been proposed.
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.
文摘为了改善离心压气机叶片多工况优化设计时面临的设计空间大、冗余搜索、灵活性不足、优化效率低等问题,提出了基于自由曲面变形技术(free form deform,FFD)的离心压气机复杂曲面叶片参数化方法,建立了叶片局部几何区域与三维空间网格控制体的映射模型,研究了样条曲线基函数几何特性对叶片几何构型的影响,实现了离心压气机叶片几何外形的局部精细化改型.结合B样条基FFD参数化方法、多目标进化算法和计算流体动力学对复杂叶片的局部区域进行了多工况气动寻优,优化结果表明:在满足约束条件的情况下,流场结构得到进一步的改善,额定工况和常用工况等熵效率分别提高了0.48%和0.40%,喘振裕度分别提升了1.6%和1.8%,利用较少的设计变量实现了离心压气机复杂曲面叶片高效灵活的精细化设计,为离心叶轮的气动优化设计提供了新的理论依据.
