离心泵内部流动数值模拟与优化设计

发布时间：2018-07-04 18:48

本文选题：离心泵 + 水力模型　；参考：《沈阳航空航天大学》2014年硕士论文

【摘要】：随着离心泵的应用范围的增大和能源的短缺,离心泵的优化设计越来越重要。目前,离心泵的优化设计大都是以单目标优化设计为主,没有考虑到离心泵的综合性能；很多优化设计方法有自身的缺陷。本文以离心泵的效率、汽蚀性能和稳定性为目标函数,以影响离心泵的主要几何参数为自变量,考虑离心泵叶轮和蜗壳的最佳匹配关系,采用Matlab优化工具箱中的遗传算法进行了离心泵多目标优化设计。采用Fluent分析软件进行了数值模拟,并通过实验证明了优化方法和优化结果的正确性和有效性。本文阐述了计算流体力学(CFD)技术和离心泵优化设计的国内外研究现状和发展趋势。在考虑离心泵蜗壳和叶轮的最佳匹配关系情况下,以离心泵的效率、汽蚀性能和稳定性为因变量,影响离心泵性能的主要几何参数D2、β2、b2、D1、β1、b1、z、Y为设计变量,建立分目标函数,根据性能指标的重要程度,确定分目标函数的权重因子,通过线性加权的方法统一目标函数,根据经验公式和企业生产要求确定合适的边界条件,并采用Matlab工具箱中遗传算法进行了优化。根据优化结果,建立新的离心泵水力模型,采用UG软件对优化前后的离心泵流体区域进行三维建模,采用gambit软件对流体区域进行网格划分,然后导入fluent软件中进行数值模拟。将优化前后的流场进行对比分析,发现优化后的叶片进口低压区的压力值高于优化前的压力值,流道中相对速度流线分布比优化前的更合理,蜗壳出口处漩涡更小。对优化前后的结果进行了实验分析。结果表明：在额定工况下,优化后的离心泵效率比优化前高5.03%,扬程低0.67m,扬程曲线更平缓,稳定性更好,从而证明了优化设计方法和数值模拟的正确性和有效性。
[Abstract]:With the enlargement of the application range of centrifugal pump and the shortage of energy, the optimization design of centrifugal pump is becoming more and more important. At present, the optimization design of centrifugal pump is mainly based on single objective optimization design, without considering the comprehensive performance of centrifugal pump; many optimization design methods have its own defects. This paper is based on the efficiency of centrifugal pump, cavitation performance and the performance of centrifugal pump. The stability is the objective function, which takes the main geometric parameters of the centrifugal pump as the independent variable and the optimum matching relation of the centrifugal pump impeller and the volute. The multi-objective optimization design of the centrifugal pump is carried out by using the genetic algorithm in the Matlab optimization toolbox. The numerical simulation is carried out with the Fluent analysis software, and the optimization method is proved by the experiment. The correctness and effectiveness of the results are optimized.
This paper describes the research status and development trend of computational fluid dynamics (CFD) technology and centrifugal pump optimization design at home and abroad.
Considering the optimal matching relationship between the centrifugal pump volute and the impeller, the main geometric parameters, D2, beta 2, B2, D1, beta 1, B1, Z, Y, are the main geometric parameters affecting the performance of centrifugal pump, with the efficiency of the centrifugal pump, the cavitation performance and stability as the dependent variable, and the objective function is established, and the weight factor of the objective function is determined by the importance of the performance index. The objective function is unified by the linear weighting method, and the appropriate boundary conditions are determined according to the empirical formula and the production requirements of the enterprise, and the genetic algorithm in the Matlab toolbox is used to optimize it.
According to the optimization results, a new centrifugal pump hydraulic model is set up. UG software is used to model the fluid region of the centrifugal pump before and after the optimization. Gambit software is used to mesh the fluid area. Then the numerical simulation is introduced into the FLUENT software. The flow field before and after the optimization is compared and analyzed, and the optimized blade inlet is found to be low. The pressure value in the pressure zone is higher than that before the optimization. The streamline distribution in the runner is more reasonable than that before the optimization, and the vortex at the outlet of the volute is smaller.
The results of the optimization have been tested and analyzed. The results show that the efficiency of the optimized centrifugal pump is 5.03% higher than that before the optimization, the lift is low 0.67M, the lift curve is more flat and the stability is better, which proves the correctness and effectiveness of the optimization design method and numerical simulation.
【学位授予单位】：沈阳航空航天大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TH311

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