Experimental investigation and numerical analysis of unsteady attached sheetcavitating flows in a ce

来源 :Journal of Hydrodynamics | 被引量 : 0次 | 上传用户:skywalker0123
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
This paper studies the attached sheet cavitation in centrifugal pumps. A pump casted from Perspex is used as the test subject. The cavitation bubbles were observed in the entrance of the impeller and the drops of the head coefficients were measured under different operating conditions. A Filter-Based Model (FBM), derived from the RNG k εmodel, and a modified Zwart model are adopted in the numerical predictions of the unsteady cavitating flows in the pump. The simulations are carried out and the results are compared with experimental results for 3 different flow coefficients, from 0.077 to 0.114. Under four operating conditions, qualitative comparisons are made between experimental and numerical cavitation patterns, as visualized by a high-speed camera and described as isosurfaces of the vapour volume fraction = v 0.1. It is shown that the simulation can truly represent the development of the attached sheet cavitation in the impeller. At the same time, the curves for the drops of the head coefficients obtained from experiments and calculations are also quantitatively compared, which shows that the decline of the head coefficients at every flow coefficient is correctly captured, and the prediction accuracy is high. In addition, the detailed analysis is made on the vapour volume fraction contours on the plane of span is 0.5 and the loading distributions around the blade section at the midspan. It is shown that the FBM model and the modified Zwart model are effective for the numerical simulation of the cavitating flow in centrifugal pumps. The analysis results can also be used as the basis for the further research of the attached sheet cavitation and the improvement of centrifugal pumps. This paper studies the attached sheet cavitation in centrifugal pumps. A pump casted from Perspex is used as the test subject. The cavitation bubbles were observed in the entrance of the impeller and the drops of the head coefficients were measured under different operating conditions. -Based Model (FBM), derived from the RNG k εmodel, and a modified Zwart model are adopted in the numerical predictions of the unsteady cavitating flows in the pump. The simulations are carried out and the results are compared with experimental results for 3 different flow coefficients, from 0.077 to 0.114. Under four operating conditions, qualitative comparisons are made between experimental and numerical cavitation patterns, as visualized by a high-speed camera and described as isurfaces of the vapor volume fraction = v 0.1. It shows shown the simulation can truly represent the development of the attached sheet cavitation in the impeller. At the same time, the curves for the drops of the h ead coefficients obtained from experiments and calculations are also quantitatively compared, which shows that the decline of the head coefficients at every flow coefficient is correctly captured, and the prediction accuracy is high. In addition, the detailed analysis is made on the vapor volume fraction contours on the plane of span is 0.5 and the loading distributions around the blade section at the midspan. It is shown that the FBM model and the modified Zwart model are effective for the numerical simulation of the cavitating flow in centrifugal pumps. The analysis results can also be used as the basis for the further research of the attached sheet cavitation and the improvement of centrifugal pumps.
其他文献
6月,学期快要结束的时候,天气格外地炎热。小孩们于是养成一个习惯,他们把各自从家里带来的塑料水瓶装满水,课间休息的时候玩洒水的游戏。老师们也不阻止小孩们的水仗游戏,实
在当前公共安全问题层出的中国社会中,政府无益要在在安全管理中起主导地位,但作为公民社会的主体,社会组织的作用也不容小觑,只有合理充分地发挥其作用,才能使公共安全问题
请下载后查看,本文暂不支持在线获取查看简介。 Please download to view, this article does not support online access to view profile.
期刊
时下,优化组合已成为“热门”话题。但从有些单位组合的情况看,与其说是优化组合,不如说是“亲化组合”、“帮化组合”更确切。因为整个组合过积没有休现一个“优”字。之所
请下载后查看,本文暂不支持在线获取查看简介。 Please download to view, this article does not support online access to view profile.
期刊
从2011年开始,裤G每周三下午4点准时守候在电脑前,通过QQ与大家在线交流。不过,由于时间有限,每次只能接待几个小读者,每个小读者只能与裤G交流10分钟,大家可不要挤破头哟!(
期刊
在约旦首都安曼以南200多公里处,在荒漠的山岩上矗立着一座由悬崖峭壁所包围的名叫皮特拉的古迹。尽管现在这里到处是断垣残壁、满目疮痍,但是在两千多年前,它原是约旦境内
近年来,企业承包取得了较突出的经济效益,但有些企业也出现了令人忧虑的现象:职工主人翁责任感失落,雇佣观念滋生,职工与承包者产生对立情绪,严重挫伤了职工的积极性。据对
在四川渠县供销社,一台彩电到了售货员手里,如在过去,售货员的责任就在于保证这台彩电存在,说得简单些,不丢失就行,卖得出去当然好,卖不出去也无所谓。至于这台彩电是否受损
意大利南部一个不被人们注意的省城——勒佐加拉勃利亚,今天却成为艺术爱好者和历史学的向往之地,因为在这里展出了世界罕见的艺术珍品——海底发现的青铜两勇士。 1972年,