Study on Flow Induced Vibration Mechanism and Its Critical Velocity of Tube Bundle

管束流激振动机理及其临界速度研究

• 批准号: 06650286
• 负责人: TANAKA Hiroki
• 金额: $ 1.22万
• 依托单位: KYUSHU INSTITUTE OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06650286/
• 关键词: Tube Bundle; Flow Induced vibration; Critical Velocity; Reduced Velocity; Unsteady Fluid Dynamics; Eqyation of Motion

Equation of motion of each tubes in bundle which is forced by unsteady fluid dynamic forces was cleared in this study. Vibration with Multidegree of freedom was applied to calculate the critical velocity at which flow induced vibration starts and equation for calculation was induced. So that, critical velocity of ninni no tube bundle can be calculated if structural characteristics and unsteady fluid dynamics are know.Unsteady fluid dynamic forces are consist of two kind of forces, one is induced by its own moving and the another is by moving of the other tube. These fluid forces were set on a steady support. Strain gages were obtained by experiment. On experiment, one cylinder is mounted on oscillator and the other cylinders were put on each support bar to obtain fluid dynamic forces acting on the tube. Signal from the strain gages had great noise which was generated by the oscillator or other moving parts. It was considered how to remove the noise in early stage and several method were tried. However, we could not fined out any useful method and after that, digital filter and Fourie expansion were used to remove the noise in calculation.One tube has two kind of freedom and fluid dynamic force also has two component. It is necessary to know 8 kinds of fluid dynamic forces which vary with reduced velocity. All fluid dynamic forces were obtained by the experiment and critical flow velocities at which vibration will start were calculated. It was cleared that the method of estimation is useful to judge whether vibration will occur or not.

明确了各管束在非定常流体动力作用下的运动方程。应用多自由度振动计算流致振动的临界速度，并推导出计算方程。因此，在已知结构特征和非定常流体动力学的情况下，可以计算出尼尼无管束的临界速度。非定常流体动力由两种力组成，一种是由其自身运动引起的力，另一种是由另一管运动引起的力。这些流动的力量是建立在一个稳定的支撑上的。通过实验获得了应变片。在实验中，一个圆柱体安装在振荡器上，另一个圆柱体安装在每个支撑杆上，以获得作用在管子上的流体动力。应变片的信号有很大的噪声，这是由振荡器或其他运动部件产生的。对如何在早期消除噪声进行了考虑，并尝试了几种方法。然而，我们没有找到任何有用的方法，然后用数字滤波和傅立叶展开来去除计算中的噪声。一根管子有两种自由度，流体动力也有两种分量。需要知道随折减速度变化的8种流体动力。通过实验得到了所有的流体动力，并计算出了启动振动的临界流速。结果表明，该估计方法对判断是否会发生振动具有一定的实用价值。

项目成果

田中博喜 他: "二本の円柱に作用する非定常流体力の研究" 機械学会北九州地方講演会論文集. No948-3. 218-220 (1994)

Hiroki Tanaka 等人：“作用于两个气缸的非定常流体力的研究”日本机械工程师学会北九州地区会议论文集 No948-220（1994 年）。

Hiroki TANAKA,etc.-: "Unsteady fluid dynamic forces acting on arbitrary moving body" Kitakyushu District Meeting of JSME. No.948-3. 224 (1994)

Hiroki TANAKA 等-：“作用于任意移动体的非定常流体动力”JSME 北九州地区会议。

Hiroki TANAKA,etc.: "Unsteady fluid forces on two cylinders and its critical velocity" The 73 rd JSME Fall Annual Meeting. No.95-10 vol.2. 131 (1995)

Hiroki TANAKA等：“两个气缸上的非定常流体力及其临界速度”第73届JSME秋季年会。

Hiroki TANAKA,etc.: "Unsteady fluid forces on tube bundle estimated by vortex method" The 73 rd JSME Fall Annual Meeting. No.95-10 vol.2. 133 (1995)

Hiroki TANAKA 等：“用涡流法估计管束上的不稳定流体力” 第 73 届 JSME 秋季年会。

田中博喜 他: "正方配列の円柱群に働く非定常流体力の研究" 機械学会北九州地方講演会論文集. No948-3. 221-223 (1994)

Hiroki Tanaka 等人：“作用于圆柱体方形阵列上的非稳态流体力的研究”日本机械工程师学会北九州地区会议记录第 221-223 号（1994 年）。