Monthly Archives: October 2014



日時: 平成26年12月1日(月) 14:40-15:40
場所: 京都大学 桂キャンパスCクラスタ総合研究棟III(C3棟) 3階 b3n03室(航空宇宙工学専攻会議室)
講演: Singularity of macroscopic variables near boundary for gases  with  cut-off  hard potential
Dr. I-Kun Chen
(Graduate School of Informatics, Kyoto University, Japan)
要旨: The boundary singularity for stationary solutions of the linearized Boltzmann equation with cut-off hard potential is analyzed. A technique of using the Holder type  continuity of the integral operator to obtain the integrability of the derivatives of  the macroscopic variables is developed. We establish the asymptotic approximation for the gradient of the moments. Our analysis indicates the logarithmic singularity of the gradient of the moments. In particular, our theorem holds for the condensation and evaporation problem.



日時: 平成26年10月20日(月) 14:30-15:30
場所: 京都大学 桂キャンパスCクラスタ総合研究棟III(C3棟) 3階 b3n03室(航空宇宙工学専攻会議室)
講演: Lagrangian Particle Simulations of Fluid Vortices
Prof. Robert Krasny
(Department of Mathematics, University of Michigan, USA)
要旨: We review some recent Lagrangian particle simulations of fluid vortices. Two examples are discussed, (1) vortex ring instability in 3D flow, and (2) vortex dynamics on a rotating sphere. These simulations use the Biot-Savart integral to recover the velocity from the vorticity, adaptive particle discretizations, and a tree code to reduce the CPU time from $O(N^2)$ to $O(N\log N)$, where $N$ is the number of particles.