轴流压气机气动数值优化设计与分析

发布时间：2018-07-01 16:58

本文选题：叶轮机械 + 跨音压气机　；参考：《中国科学院研究生院（工程热物理研究所）》2011年硕士论文

【摘要】：先进的涡轮动力系统对风扇/压气机气动性能的要求不断提高,不断发展和完善的设计方法及工具是完成日益苛刻的设计要求的重要保证。以粘性、全三维气动数值模拟为分析手段的设计技术日益成熟,而气动数值优化设计在现代设计体系中发挥着越来越重要的作用,并已成为叶轮机械领域的研究热点。本文以某单级跨音压气机为研究对象,以提高其压比、效率和扩大稳定工作范围为目标,对该压气机进行了多目标气动优化,并着重分析了提高跨音级压气机气动性能的关键因素。本文首先对原型压气机进行全三维数值模拟,数值求解相对坐标系下的三维、粘性Navier-Stokes雷诺平均方程,计算结果表明该数值方法能很好的预测跨音速轴流压气机的性能,保证了计算的可靠性。优化设计系统分为三个模块：参数化方法、全三维流场评价和寻优算法。参数化采用Bezier曲线重构原始压气机几何型线(子午通道、叶片),先后通过反算控制顶点和拟合寻优以减小构造曲线和原始型线的误差,尽可能达到精确逼近的效果；全三维流场计算及评价目的是对设计参数进行性能评估,以供优化算法进行优劣比较并做出裁决；寻优算法是设计系统的核心部分,它直接决定了寻优的效率和效果,本文采用基于人工神经网络(ANN)和遗传算法(GA)的复合寻优策略。神经网络作为一种近似模型,用于缩小问题的求解规模,遗传算法作为一种模拟自然进化机制的算法,理论上可以达到全局寻优,实际应用中给定适当的参数,遗传算法可以在较大的设计空间内搜索到良好的结果。应用该优化设计系统,本文首先针对叶片积叠线进行优化,旨在探索积叠线对跨音级压气机性能的影响。研究表明,弯掠设计可以改善叶轮机械内部流动,调整激波位置和强度,使负荷在弦向和展向得以重新分配,具有重新组织流动的效用。积叠线优化表明,弯、掠两个维度的联合使用可以明显的提高压气机的性能。压气机内部的流动状况和负荷的分布还与二维叶型密切相关,本文第二阶段的三维优化,既考虑积叠线,又兼顾叶型的修改,实现了压气机性能的进一步提升。
[Abstract]:The requirements of the advanced turbine power system to the aerodynamic performance of the fan / compressor are increasing, and the continuous development and perfection of the design methods and tools are the important guarantee to complete the demanding design. The design technology of the viscous, all three-dimensional aerodynamic numerical simulation is increasingly mature, and the Aerodynamic Numerical Optimization Design is in the modern design. The system is playing a more and more important role and has become a hot research topic in the field of turbomachinery. In this paper, a single stage transonic compressor is taken as the research object to improve its pressure ratio, efficiency and expand the stable working range. The multi-objective aerodynamic optimization of the compressor is carried out, and the aerodynamic performance of the transonic compressor is emphatically analyzed. The key factor in energy.
In this paper, the three-dimensional numerical simulation of the prototype compressor is carried out, and the numerical solution of the three-dimensional and viscous Navier-Stokes Reynolds mean equation in the relative coordinate system is numerically solved. The calculation results show that the numerical method can predict the performance of the transonic axial compressor well and ensure the reliability of the calculation. The optimization design system is divided into three modules: parameterization The Bezier curve is used to reconstruct the geometric line of the original compressor (Meridian channel and blade) parameterized. The error of the structure curve and the original line is reduced by the inverse control vertex and the fitting optimization, and the effect of accurate forcing is achieved as much as possible. The performance evaluation of the design parameters is made for the optimization algorithm to compare and make a decision. The optimization algorithm is the core part of the design system. It directly determines the efficiency and effect of optimization. In this paper, a complex optimization strategy based on artificial neural network (ANN) and genetic algorithm (GA) is adopted. The genetic algorithm, as an algorithm to simulate the natural evolution mechanism, can achieve global optimization in theory. In practical application, the genetic algorithm can search for good results in a larger design space.
In this paper, the optimal design system is used to optimize the blade stacking line. The aim of this paper is to explore the effect of stacked line on the performance of the transonic compressor. The study shows that the bending design can improve the internal flow of the turbomachinery, adjust the position and strength of the shock wave, redistribute the load in the chord direction and direction, and have the effect of reorganizing the flow. The combined use of stacked line shows that the combined use of two dimensions can obviously improve the performance of the compressor. The flow status in the compressor and the distribution of the load are closely related to the two-dimensional leaf type. In this paper, the three-dimensional optimization of the second stage not only considers the stacking line, but also considers the modification of the blade type, thus realizing the further improvement of the compressor performance.
【学位授予单位】：中国科学院研究生院（工程热物理研究所）
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH453

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