Study of Flow-Induced Vibrations in a Rotating Double Disk Immersed in a Confined Water

浸入承压水中的旋转双盘的流激振动研究

基本信息

批准号：
61460115
负责人：
HARA Fumio
金额：
$ 3.71万
依托单位：
Science University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1986
资助国家：
日本
起止时间：
1986 至 1987
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61460115/
关键词：
Single disk Double disk Rotation in water Vebration Swirling flow Buckling mode static deformation Single-diametor-node-line mode vabration out-of-phase mode vibration 回転ディスク流体不安定振動ヒステリシス特性水中ディスクレーザドップラ振動計

项目摘要

This report deals with experimental studies of vibration characteristcs of disks rotating in a confined water. Two type of disks were examined; one was a single disk 350 mm in diameter and 1 mm thick, and the other was a double disk consisting of two identical disks having a disk gap of 7 mm. The double disk size was the same as that of a single disk. Both disk systems were immersed in water confined by a shrouds. The gap between the shroud-wall and the disk was 7 mm for both systems. Changing rotation speed from 3 rps to 7rps, we measured the diaplacement of disk at two points diagonal to each other and pressure fluctuation on the shroud wall. Data were recorded on magneic tape and digitized to be stored in a microcumputer. We calculated the mean, root mean square, power spectral density and phase angle for these data and found the following major results:1. A single disk underwent a unstable vibration a a certain rotation speed and this vibration became a more severe vitration at hig … More her rotation speed.2. Vibration amplitude of a rotating single disk had a hysteresis for increasing and decreasing rotation speed.3. The mode of the unstable vibrations was out-of-phase between two diagonal points on the disk.4.The hysteresis was also found in the relationship between rotation speed and the dominant frequency of the disk vibration as well as in that between the mean value of disk displacement or static displacement and rotation speed.5. For a double disk we found two large vibrations for different rotation speed ranges but no hysteresis was found for the double disk having holes at the fixed part to the driving shaft.6.The unstable vibrations in a double disk was out-of-phase with respect to the disk diameter.7 The double disk underwent a buckling mode static deformation.From these experimental results we concluded-that a disk rotating in a confined fluid undergoes therr type of deformations: one is a static, or buckling mode deformation, the other two were out-of-phase mode vibrations with different dominant frequencies. Less

该报告涉及旋转在受限水中旋转的磁盘的振动特征的实验研究。检查了两种类型的磁盘；一个是直径350毫米的单个盘，厚1毫米，另一个是一个双盘，由两个磁盘间隙为7 mm的相同磁盘组成。双磁盘尺寸与单个磁盘的大小相同。两个磁盘系统都浸入了被裹尸布限制的水中。罩壁和磁盘之间的差距从3 rps变为7 rps，我们测量了两个点对角线的磁盘的隔膜，并在裹尸布壁上测量了压力波动。将数据记录在磁带上，并数字化以存储在微关头中。我们计算了这些数据的平均值，均方根，功率谱密度和相角，并找到了以下主要结果：1。单个磁盘经历了一个不稳定的振动，以一定的旋转速度，这种振动在高度的旋转速度上变得更加严重。2。旋转单盘的振动幅度具有增加和降低旋转速度的磁滞3。不稳定振动的模式在磁盘上的两个对角点之间存在相位。4。在旋转速度与磁盘振动的主要频率之间的关系以及磁盘位移的平均值或静态位移和旋转速度之间的关系之间也发现了滞后。5。对于双磁盘，我们发现了两个用于不同旋转速度范围的大振动，但没有发现双盘在驾驶轴的固定部分上有孔的孔。经历therr类型的变形类型：一种是静态或屈曲模式变形，另外两个是具有不同显性频率的相位模式振动。较少的