共查询到20条相似文献,搜索用时 31 毫秒
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OPTIMIZATION METHOD ON IMPELLER MERIDIONAL CONTOUR AND 3D BLADE 总被引:1,自引:0,他引:1
LU Jinling XI Guang QI Datong 《机械工程学报(英文版)》2007,20(6):43-49
An optimization method for 3D blade and meridional contour of centrifugal or mixed-flow impeller based on the 3D viscous computational fluid dynamics (CFD) analysis is proposed. The blade is indirectly parameterized using the angular momentum and calculated by inverse design method. The design variables are separated into two categories: the meridional contour design variables and the blade design variables. Firstly, only the blade is optimized using genetic algorithm with the meridional contour remained constant. The artificial neural network (ANN) techniques with the training sample data schemed according to design of experiment theory are adopted to construct the response relation between the blade design variables and the impeller performance. Then, based on the ANN approximated relation between the meridional contour design variables and impeller performance, the meridional contour is optimized. Fewer design variables and less calculation effort is required in this method that may be widely used in the optimization of three-dimension impellers. An optimized impeller in a mixed-flow pump, where the head and the efficiency are enhanced by 12.9% and 4.5% respectively, confirms the validity of this newly proposed method. 相似文献
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为了研究螺旋离心泵叶轮做功原理以及能量转换机理,应用计算流体力学原理对100LN-7型螺旋离心泵进行数值模拟,由此获得螺旋离心泵叶轮域速度参数,在引入动静扬程和负荷系数基础上,将欧拉方程用速度表示,建立试验方案。在叶片负荷翼型理论下,应用欧拉方程将螺旋离心泵的能量转换与叶轮几何形状、尺寸联系起来,分析沿叶轮包角的能量变化,揭示螺旋离心泵叶轮域能量转换特性。结果表明叶轮作为泵内做功核心部件,其螺旋段螺旋推进作用提供了能量传递,离心段完成能量转换,叶轮的螺旋段螺旋推进作用和离心段的能量转换相互配合,构成了螺旋离心泵工作的过程。其中,叶片翼型负荷中的升力对叶片做功贡献最大,这一结论对于提高螺旋离心泵叶轮水力设计具有重要的意义。 相似文献
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Cavitation is one of the most important performance of centrifugal pumps. However, the current optimization works of centrifugal pump are mostly focusing on hydraulic efficiency only, which may result in poor cavitation performance. Therefore, it is necessary to find an appropriate solution to improve cavitation performance with acceptable efficiency. In this paper, to improve the cavitation performance of a centrifugal pump with a vaned diffuser, the influence of impeller geometric parameters on the cavitation of the pump is investigated using the orthogonal design of experiment(DOE) based on computational fluid dynamics. The impeller inlet diameter D_1, inlet incidence angle Δβ, and blade wrap angle φ are selected as the main impeller geometric parameters and the orthogonal experiment of L_9(3*3) is performed. Three-dimensional steady simulations for cavitation are conducted by using constant gas mass fraction model with second-order upwind, and the predicated cavitation performance is validated by laboratory experiment. The optimization results are obtained by the range analysis method to improve cavitation performance without obvious decreasing the efficiency of the centrifugal pump. The internal flow of the pump is analyzed in order to identify the flow behavior that can affect cavitation performance. The results show that D_1 has the greatest influence on the pump cavitation and the final optimized impeller provides better flow distribution at blade leading edge. The final optimized impeller accomplishes better cavitation and hydraulic performance and the NPSHR decreases by 0.63 m compared with the original one. The presented work supplies a feasible route in engineering practice to optimize a centrifugal pump impeller for better cavitation performance. 相似文献
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介绍了低比速离心泵特点,阐述计算的控制方程和叶轮通道网格划分方法.运用CFD软件FLUENT对不同叶片形式叶轮流道进行三维湍流流动计算.计算采用压强连接的隐式修正SIMPLEC算法和雷诺平均法的RNG k-ε湍流模型.根据计算结果分析叶片形式对流速分布、压力分布的影响,揭示叶轮内流动规律,提高低比速离心泵优化设计的水平. 相似文献
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长短叶片离心泵汽蚀性能数值模拟分析及实验研究 总被引:2,自引:0,他引:2
为提高离心泵的汽蚀性能,利用CFD数值模拟分析与实验研究相结合的方法对长短叶片离心泵在不同汽蚀余量时叶轮内部气液两相的分布规律进行分析研究,分析了3种不同短叶片进口直径在不同汽蚀工况时气泡分布情况对叶轮内部流动和性能的影响。分析结果表明:选择合理短叶片的进口直径可以有效提高离心泵的抗汽蚀性能,避免叶轮进口堵塞和流道内发生漩涡汽蚀。当汽蚀余量减小到一定程度,离心泵短叶片进口直径为0.65D2(D2为叶轮外径)时,在长叶片和短叶片的背面都会出现漩涡汽蚀区;当离心泵短叶片进口直径为0.75D2时,在长叶片背面与短叶片工作面间的流道内会出现两个漩涡汽蚀区;当离心泵短叶片进口直径为0.85D2时,离心泵的抗汽蚀性能最佳。 相似文献
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The existing research on improving the hydraulic performance of centrifugal pumps mainly focuses on the design method and the parameter optimization. The traditional design method for centrifugal impellers relies more on experience of engineers that typically only satisfies the continuity equation of the fluid. In this study, on the basis of the direct and inverse iteration design method which simultaneously solves the continuity and motion equations of the fluid and shapes the blade geometry by controlling the wrap angle, three centrifugal pump impellers are designed by altering blade wrap angles while keeping other parameters constant. The three-dimensional flow fields in three centrifugal pumps are numerically simulated, and the simulation results illustrate that the blade with larger wrap angle has more powerful control ability on the flow pattern in impeller. The three pumps have nearly the same pressure distributions at the small flow rate, but the pressure gradient increase in the pump with the largest wrap angle is smoother than the other two pumps at the design and large flow rates. The pump head and efficiency are also influenced by the blade wrap angle. The highest head and efficiency are also observed for the largest angle. An experiment rig is designed and built to test the performance of the pump with the largest wrap angle. The test results show that the wide space of its efficiency area and the stability of its operation ensure the excellent performance of the design method and verify the numerical analysis. The analysis on influence of the blade wrap angle for centrifugal pump performance in this paper can be beneficial to the optimization design of the centrifugal pump. 相似文献
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Li JunInstitute of Turbomachinery School of Energy & Power Engineering Xi''''an Jiaotong University Xi''''an ChinaLiu LijunResearch Institute for Applied Mechanics Kyushu University Fukuoka - JapanFeng ZhenpingInstitute of Turbomachinery School of Energy & Power Engineering Xi''''an Jiaotong University Xi''''an China 《机械工程学报(英文版)》2004,17(3):389-393
Application of the multiobjective evolutionary algorithms to the aerodynamic optimization design of a centrifugal impeller is presented. The aerodynamic performance of a centrifugal impeller is evaluated by using the three-dimensional Navier-Stokes solutions. The typical centrifugal impeller is redesigned for maximization of the pressure rise and blade load and minimization of the rotational total pressure loss at the given flow conditions. The Bezier curves are used to parameterize the three-dimensional impeller blade shape. The present method obtains many reasonable Pareto optimal designs that outperform the original centrifugal impeller. Detailed observation of the certain Pareto optimal design demonstrates the feasibility of the present multiobjective optimization method tool for turbomachinery design. 相似文献
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几何参数对离心叶轮强度和气动性能影响的研究 总被引:2,自引:0,他引:2
使用有限元计算软件和内部流场计算软件对所设计的几个具有不同几何尺寸的离心压气机叶轮的强度和气动性能进行了计算。结果表明反弯叶片可降低叶轮出口处叶片根部附近的应力,但会造成叶片根部前缘区域应力集中,且反弯叶轮的气动性能和原型叶轮差别不大。前倾叶片能在很大程度上降低叶轮出口处叶片根部应力,前倾角越大出口叶根处应力减小越多;随前倾角增大,叶轮气动性能恶化程度加剧;叶轮的背盘形状对叶轮的应力影响较大,尤其是出口处的背盘厚度对出口处叶片根部区域的应力起主因作用。研究得出叶片几何及背盘形状因素对叶轮应力分布的影响规律,另外还得到了叶片几何形状对气动性能的影响规律,这些工作为叶轮的多学科优化设计提供良好的基础。 相似文献