共查询到17条相似文献,搜索用时 328 毫秒
1.
为研究导叶时序对多级离心泵性能的影响,通过搭建试验台同步测试不同导叶时序位置下多级离心泵外特性和振动特性。定义4个因素A、B、C、D,每个因素设有0°和30°两个水平,共设计8个导叶时序正交方案。试验结果表明,不同时序方案下,多级泵扬程、效率均有略微提高,提高幅度在0.5%以内。多级泵导叶时序对离心泵进出口振动速度影响较大,5级泵前两级泵级导叶交错布置可降低一倍轴频处的进口振动幅值,降幅达25%左右,后2个泵级导叶交错布置能降低一倍轴频处泵出口振动速度幅值,最大降低幅值为30%。无导叶时序下,多级泵进出口振动速度较大,出口振动速度为进口振动速度一倍多,出口振动更为剧烈。研究结果可为多级离心泵减振降噪提供参考。 相似文献
2.
为了研究多级导叶式离心泵转子运行特性,以五级导叶式离心泵为研究对象,采用ANSYS模块下的Woekbench对该五级导叶式离心泵进行无预应力和有预应力下的模态计算。结果表明,旋转离心力对固有频率的影响大于流固耦合力;在同时考虑流固耦合力和旋转离心力的条件下,该五级离心泵的固有频率介于只考虑旋转离心力和只考虑流固耦合力之间,且各阶临界转速更接近只考虑旋转离心力时的临界转速;旋转离心力对各阶振幅的影响较小,而流固耦合力对各阶振幅的影响较大;额定转速小于1阶临界转速的0.8倍,该五级导叶式离心泵转子系统是一个稳定的刚性系统。 相似文献
3.
本文以一六级多级离心泵为模型,设计A、B、C、D四组不同的交错方案,A为叶轮相位不交错、 B为叶轮相位交错一个流道相位的1/2、C为叶轮相位交错一个流道的1/(Z-1)、D为叶轮相位交错一个导叶流道的1/(Z-1)(其中Z叶轮为叶片数)。通过四组方案对多级离心泵的三维全流场进行数值分析,得到不同叶轮交错方案在不同工况条件下流场对机械部件的荷载变化。分析结果表明:叶轮相位交错使转子的径向力矢量分布向轴心集中;叶轮相位交错结构可以有效地减小转子受到的径向力,使转子运行稳定性得到提高;叶轮相位交错会造成不同工况下的转子受力波动幅值和成分发生改变;在设计工况下数值计算轴向力绝对值要高于理论计算的结果 相似文献
4.
《热能动力工程》2017,(11)
以多级离心泵为模型,设计A、B、C、D 4组不同的交错方案,A为叶轮相位不交错、B为叶轮相位交错一个流道相位的1/2、C为叶轮相位交错一个流道的1/(Z-1)、D为叶轮相位交错一个导叶流道的1/(Z-1)(其中Z为叶轮叶片数)。通过4组方案对多级离心泵的三维全流场进行数值分析,得到不同叶轮交错方案在不同工况条件下流场对机械部件的荷载变化。分析结果表明:叶轮相位交错使转子的径向力矢量分布向轴心集中;叶轮相位交错结构可以有效地减小转子受到的径向力,使转子运行稳定性得到提高;叶轮相位交错会使得不同工况下的转子受力波动幅值和成分发生改变;在设计工况下数值计算轴向力绝对值要高于理论计算的结果。 相似文献
5.
从电厂SIS系统中提取数据,建立汽轮发电机组振动故障诊断相关和偏相关分析模型,分析变工况运行时各振动测点之间以及振动和过程参数之间的相关性规律,结合某600MW汽轮发电机振动故障实例进行了分析。研究结果表明,相关性特征反映了设备物理背景,可以有效地指导电厂设备故障诊断,提高数据挖掘的针对性。变工况运行时参数都在变化,参数之间的相互影响较大,偏相关分析更能展现出两两变量之间的净相关关系,可以减少故障诊断专项试验所需费用和时间。振动分析时的相关性特征包括:同一轴承座上轴振之间、轴振和瓦振之间、相邻轴承振动之间以及振动和过程参数之间等。如相关性质发生变化,需要进一步分析偏差的原因。 相似文献
6.
7.
为研究卧式多级离心泵转子系统发生振动时各个位置的谐响应规律,通过Ansys Workbench软件进行模态分析的基础上,在某型号的多级离心泵转子各级叶轮上施加激励压力,分析泵转子系统正应力响应和变形响应。结果表明,各个节点中第一级口环节点位置的变形响应和左端轴承节点位置的正应力响应幅值最大,并对第一级叶轮外径边缘上施加的激励压力最为敏感,其响应均发生在泵转子系统第2、6阶固有频率附近,其中第一级口环变形响应最大值出现在靠近叶轮进口处,左端轴承位置表面的正应力响应沿轴线呈对称分布,其上拉应力和压应力的最大值均出现在靠近轴承位置表面边缘处。 相似文献
8.
叶轮是多级离心泵中最为关键的过流部件之一,其结构对多级离心泵的外特性能和噪声特性具有重要影响。选取一典型多级离心泵为例,借助试验测量方法研究了3种叶轮结构变化下多级离心泵的性能表现和噪声特性,在M型多级离心泵专用试验台上进行多级离心泵的性能试验,并使用AS824型声级计来测量多级离心泵在不同工况下的综合噪声。结果表明,叶轮出口叶片1/2径切有助于提升多级离心泵的水力性能,但会增强其综合噪声强度;减小叶轮直径可小幅降低噪声强度,但其对噪声的抑制作用并不明显;减小叶片直径可较大幅度降低多级离心泵的综合噪声强度,但会使多级离心泵的性能明显降低,在满足性能要求的情况下可通过减小叶片直径来实现多级离心泵的降噪抑噪。 相似文献
9.
10.
11.
The side channel pump, which is a common energy conversion equipment, has undergone high developmental trends and has become very popular in recent times because of its wide applications in many fields. The side channel pump is a type of regenerative pump that plays a role in between the centrifugal pump and the positive displacement pump. This kind of pump delivers a high head at relatively small flows compared with other axial and centrifugal pumps even though it requires a low specific speed. Depending on the number of impellers used, the side channel pump can be single‐stage or multistage. This paper first focuses on the physical principle behind the internal flow characteristics illustrating the complex flow and the energy from the blade to the fluid and the side channel inside the pump. Further discussions disclosed that the hydraulic performance of the pump greatly depends on the variations of the geometrical parameters. This review draws conclusion that enhancement of the computational modeling techniques will improve the efficiency of this pump, thereby broadening its applications. 相似文献
12.
The inherently slim design of the eccentric helical pump appears to make this type of pump to be attractive for delivering water from deep wells, as compared with multistage centrifugal pumps. The basis shape of the volumeflow-head (V-H characteristics) of displacement pumps promises a more economical use of the available solar energy than possible with centrifugal pumps. This article presents the results of experiments concerning the wear in eccentric helical pumps operating with water containing abrasive particles. The temporary stability of the fluid flow and of the efficiency during delivery of abrasive suspensions is demonstrated. The results are used to derive a prognosis for the expectable service life of such a pump system. 相似文献
13.
To study the pressure distribution of the volute casing, front casing and back casing in a prototype centrifugal pump, the pressure experiments and numerical simulations are carried out at six working conditions in this paper. The experimental results shows that the asymmetry of static pressure distribution on volute casing and front cavity is caused by the tongue of the volute and it may result in high radial and axial resultant force which can cause vibration and noise in the centrifugal pump. With the increasing of flow rate, the asymmetry of static pressure distribution and the magnitude of static pressure values reduce. The numerical results indicate that the pressure fluctuation near the tongue is strongest and it becomes slighter at point away from the tongue. With the increasing of flow rate, the local high-pressure region in impeller passage reduces and the flow becomes smoother accordingly, whereas the fluid speed becomes much higher which may cause further flow losses. The results predicted by numerical simulation are in coincident with the experimental ones. It shows that the turbulence model for simulating the flow field in centrifugal pumps is feasible. 相似文献
14.
15.
16.