• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Applied Mathematical Modelling >On the flow field and performance of a centrifugal pump under operational and geometrical uncertainties
【24h】

On the flow field and performance of a centrifugal pump under operational and geometrical uncertainties

机译：在运行和几何不确定性下的离心泵的流场和性能

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Uncertainties are present in most engineering applications such as turbomachines. The performance of turbomachinery can be highly affected by the presence of uncertainties and these effects should be considered in the design procedure. The present study is the first work to quantify the impact of various uncertainties in a hydraulic machine. The paper is concerned with the combined effects of geometrical and operational uncertainties on the flow field and performance of a low specific-speed centrifugal pump. The uncertainty analysis is performed for three different flow rates, i.e.,Q/Qd=0.825,1.0and 1.1175. The volumetric flow rate, rotational speed and blade geometry of the pump are assumed to be stochastic with uniform Probability Distribution Functions (PDFs). The randomness in the blade geometry, due to the manufacturing tolerances, is imposed through two Karhunen–Loève (KL) expansions. The eigenvalues of covariance kernel of KL expansions rapidly decay due to the large correlation lengths and thus a few terms are used in the truncated KL expansion to describe the blade geometrical uncertainties. The uncertainties are propagated in the flow field and performance of the pump using the Non-Intrusive Polynomial Chaos (NIPC) method. The respective effects of assumed uncertain variables on the quantities of interest are assessed using Sobol’ indices. The uncertain operational and geometrical conditions have significant influences on the flow field and performance of the pump. It is observed that while variation of the pump head coefficient under operational and geometrical uncertainties is significant, the pump efficiency shows a robust behavior under assumed uncertain conditions.
机译：在大多数工程应用（例如涡轮机）中存在不确定性。不确定性的存在会极大地影响涡轮机械的性能，在设计过程中应考虑这些影响。本研究是量化液压机各种不确定性影响的第一项工作。本文涉及几何和操作不确定性对低比转速离心泵的流场和性能的综合影响。对三种不同的流量进行不确定度分析，即Q / Qd = 0.825、1.0和1.1175。假定泵的体积流量，转速和叶片几何形状是随机的，并且具有统一的概率分布函数（PDF）。由于制造公差，叶片几何形状的随机性是通过两次Karhunen-Loève（KL）扩展施加的。 KL展开的协方差核的特征值由于较大的相关长度而迅速衰减，因此在截短的KL展开中使用了一些术语来描述叶片的几何不确定性。使用非侵入式多项式混沌（NIPC）方法在泵的流场和性能中传播不确定性。使用Sobol指数评估假定不确定变量对感兴趣数量的各自影响。不确定的运行和几何条件会严重影响泵的流场和性能。可以观察到，尽管在运行和几何不确定性下泵头系数的变化很大，但在假定的不确定条件下，泵的效率仍表现出良好的性能。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号