面向涡轮叶片方案优化的变保真度设计系统

Variable-fidelity optimization system for turbine blade preliminary design

提出了面向涡轮叶片初始设计的变保真度的多学科设计优化方法,建立了自动化的设计系统以提高设计效率.该系统集成了分析工具和设计团队以及数据管理系统,使得设计过程自动地运行.开始设计阶段使用基于经验公式的低保真度模型;优化中的三维仿真过程使用基于精确的流体分析和结构分析的高保真度模型.过程按照模型保真度的不同分3个阶段,渐近地获得最优解,同时考虑非设计点的优化.通过实验设计搜索并逐渐缩小设计空间,使得高保真度分析所带来的计算成本得以减少.最后以一个2级轴流涡轮的叶片初始方案设计验证了本设计系统.

Variable-fidelity and multidisciplinary optimization approaches were presented and an automatic design system was developed for turbine blade preliminary design to improve design efficiency. The system integrated analysis tools and design teams, as well as data management system, which enabled performing variable-fidelity and muhidisciplinary turbine blade optimization design automatically. Low-fidelity model consisted of experiential formulation was used in the initial phase, and high-fidelity model consisted of accurate computational fluid dynamics analysis and structural analysis was used in three-dimensional simulation of optimization phase. According to fidelity of analysis model, design process was divided into three stages to attain the optimum solution gradually, and both design point and off-design point were considered during optimization. As design space was narrowed gradually and researched by design of experiment, computational cost associated with high-fidelity analysis was reduced. Finally, preliminary design for blades of an axial-flow turbine with two stages was performed to validate the system.