Grant-in-Aid for Scientific Research (A).
|Research Institution||KYOTO UNIVERSITY|
NISHIDA Takaaki Kyoto Univ. Graduate School of Sci., Professor, 大学院・理学研究科, 教授 (70026110)
池田 勉 龍谷大学, 理工学部, 教授 (50151296)
NAKAO Mitsuhiro Kyushu Univ. Graduate School of Sci., Professor, 大学院数理学研究院, 教授 (10136418)
MASUDA Kyuya Meiji Univ. Dept. of Sci. & Eng., Professor, 理工学部, 教授 (10090523)
OKAMOTO Hisashi Kyoto Univ. Research Inst. Math. Sci., Professor, 数理解析研究所, 教授 (40143359)
KOKUBU Hiroshi Kyoto Univ. Graduate School of Sci., Assoc. Professor, 大学院・理学研究科, 助教授 (50202057)
松村 昭孝 大阪大学, 大学院・理学研究科, 教授 (60115938)
堤 正義 早稲田大学, 理工学部, 教授 (70063774)
KOZONO Hideo Tohoku Univ. Graduate School of Sci., Professor, 大学院理学研究科, 教授 (00195728)
|Project Fiscal Year
1998 – 2000
Completed(Fiscal Year 2000)
|Budget Amount *help
¥27,600,000 (Direct Cost : ¥27,600,000)
Fiscal Year 2000 : ¥7,300,000 (Direct Cost : ¥7,300,000)
Fiscal Year 1999 : ¥9,200,000 (Direct Cost : ¥9,200,000)
Fiscal Year 1998 : ¥11,100,000 (Direct Cost : ¥11,100,000)
|Keywords||Nonlinear PDE / Global bifurcation structure / Bifurcation from degenerate singular points / Dynamical system / Computer assisted proof / Navier-Stokes equation / Heat convection problem / Taylor-Couette problem / 非線形偏微分方程式 / 大域的分岐構造 / 退化特異点からの分岐 / 力学系 / 計算機援用証明法 / Navier-Stokes方程式 / 熱対流問題 / Taylor問題 / 縮約系の大域的解析 / 精度保証付き数値計算 / 粘性的衝撃波 / 燃焼合成反応 / 大域的な分岐構造 / 退化特異点の摂動 / 解空間の大域的構造 / 分岐問題 / roll,六角形cell / Reynolds数,Rayleigh数 / 特異摂動的力学系|
1. Heat convection problem :
In order to investigate the global structure of the solution space of the nonlinear PDE's and to treat the global bifurcation curves in it, we worked on the analytical method combined with the computational analysis and computer assisted proof. We proposed criterions to prove the existence of solutions which correspond to parameter values as computer assited proof. Using the method we showed the existence of global bifurcation curves on which the roll-type solutions exist that correspond to large Rayleigh numbers.
In the case of 3-dimension we investigated numerically the pattern formation of roll-type, rectangle-typpe and hexagonaltype solutions and their stability, and we clarified the global bifurcation diagram which is not seen from the local bifurcation theory.
2. Taylor problem :
We considered the stability of Couette flow when the two cylinder rotate in the opposite directions. It is reduced to the eigenvalue problem for the system of ordinary differe
ntial equations and it can be treated by our computer assisted proof to see the exact critical Taylor number, at which the stationary or Hopf bifurcation occurs. The bifurcation point with multiplicity is one of our future subject.
3. The existence theorem for stationary solution of Navier-Stokes equation is proved by our numerical verification method at least for small Reynols number.
4. Dynamical systems :
We know that when the degeneracy of singular points of vector field increases, the behavior of dynamics becomes more complex and the global phenomena become more included. We investigated the singular point with codimension 3 and proved analytically that the hetero-clinic cycle bifurcates and also chaotic attractor does.
5. For the 3-dimensional exterior problem of stationary Navier-Stokes equation, we introduced a real interpolation of Morrey spaces to solve N-S equation and succeeded to construct the exterior stationary solution and to prove its stability without the unnatural zero net force conditions. Less