1987 Fiscal Year Final Research Report Summary
On the Self-Excited Oscillations of a Centrifuge Filled with Two Kinds of Liguids.
| Project/Area Number |
61550191
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
機械力学・制御工学
|
|---|
| Research Institution | Kyushu Institute of Technology |
|---|
Principal Investigator |
JINNOUCHI Y. Kyushu Institute of Tech., Professor, 工学部, 教授 (10039092)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
ARAKI Y. Kyushu Institute of Tech., Associate Peofessor, 工学部, 助教授 (40039045)
MINE K. Kyushu Institute of Tech., Professor, 工学部, 教授 (50043849)
INOUE J. (40038998)
|
|---|
| Project Period (FY) |
1986 – 1987
|
| Keywords | Self-Excited Oscillation / Flow-Induced Oscillation / Centrifuge / Rotaing Liquid / スロッシング / 遠心分離機 / 遠心力波 |
|---|
| Research Abstract |
A theoretical and experimental investigation is made into the dynamic stability of a centrifuge of two liquid type, in which the cavity is divided into fan-shaped compartments to suppress asynchronous whirling motions due to waves travelling along the free boundary between the liquids.
Assuming rotor and liquid motions to be small, liquid inviscid, and damping neglisible, perturbed motions of the liquid-rotor system are analyzed. Such a linearized formulation leads to an eigenvalue problem for the whirl frequency, which is useful to predict the stability of the system.
The results show that the rotor containing a partitioned cavity is still possible to exhibit unstable behavior in the region where the rotor speed is nearly equal to the sum of the critical speed of the rotor and the natural freguency of the liguids. In the unstable region self-excited oscillations of the rotor can be induced by waves which move back and forth in each compartment because they behave as if a single wave travels througn around the cavity. Since the natural frequency of the liquids is an increasing function of the number of the compartments and the difference in density between the liquids, with an increase in them the unstable region shifts to higher rotor speeds side until it vanishes.
|
