| Project/Area Number |
11650248
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Dynamics/Control
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| Research Institution | Hyogo University of Teacher Education |
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Principal Investigator |
KURATANI Fumiyasu Faculty of School Education, Hyogo University of Teacher Education, Associate Professor, 学校教育学部, 助教授 (00294265)
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| Co-Investigator(Kenkyū-buntansha) |
YAMANO Tadao Faculty of School Education, Hyogo University of Teacher Education, Professor, 学校教育学部, 教授 (90304138)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2000)
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| Budget Amount *help |
¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 2000: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1999: ¥2,000,000 (Direct Cost: ¥2,000,000)
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| Keywords | Vibration Property / Thin Plate / Optimization Problem / Finite Element Method / Circular Saw / Rolling / Initial Stress Stiffness Matrix |
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| Research Abstract |
When thin plates are locally compressed with opposing rollers, residual stresses are induced within the thin plates and then their vibration properties change. This research presents an optimization technique for the vibration properties of thin plates using locally rolling. Optimal rolling conditions are determined in the optimization problem assisted by computer instead of an experimental approach. A circular saw is given an actual example of a thin plate, which is widely used in cutting wood.
1. A Search Algorithm for Optimal Rolling Conditions of Circular Saws
A search algorithm based on gradient projection method is proposed for determining optimal rolling conditions (rolling position and rolling load) to maximize the lowest frequency of backward traveling wave of a rotating circular saw. In some examples, the optimal conditions are determined for several rotation speeds of a disk as a simple model of a circular saw. The results show that (1) the lowest frequency of backward traveling wave of an optimally rolled disk increases considerably, (2) the optimal conditions for the maximization of the lowest frequency of backward traveling wave vary with the rotation speed of the disk.
2. An Efficient Method for Estimating Natural Frequencies of Rolled Circular Saws
An efficient method is proposed for estimating natural frequencies of circular saws locally compressed by rolling. The proposed method easily estimates the natural frequencies of a circular saw after rolling from the natural frequencies and mode shapes of the circular saw before rolling and the initial stress stiffness matrix after rolling without eigenvalue analysis. Some examples show that (1) the natural frequencies are accurately estimated from one-dimensional eigenvalue problem when rolling loads are small, (2) when the difference between the mode shapes before and after rolling is large, the coupled eigenvalue problem must be solved. In this case, the small-sized eigenvalue problem can be sufficient.
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