数値解析・応用解析セミナー

10月4日(火) 15:30 -- 17:00  Olivier Pironneau
                           (Laboratoire Jacques-Louis Lions,
                            Sorbonne-Universite, France)
              "Numerical Methods for the Radiative Transfer Equations
             for the Atmosphere"

＜研究発表要旨＞
To study the temperature in a gas subjected to electromagnetic
radiations, one may use the Radiative Transfer equations coupled
with the Navier-Stokes equations. The problem has 7 dimensions;
however with minimal simplifications it is equivalent to a small
number of integro-differential equations in 3 dimensions.
We present the method and a numerical implementation using an
H-matrix compression scheme. The result is a very fast: 50K physical
points, all directions of radiation and 680 frequencies require
less than 5 minutes on an Apple M1 Laptop. The method is capable
of handling variable absorption and scattering function S of
spatial positions and frequencies.
  The implementation is done using "htool", a matrix compression
library interfaced with the PDE solver "freefem++". Applications
to the temperature in the French Chamonix valley is presented at
different hours of the day with and without snow / clouds and
with a variable absorption taken from the Gemini measurements.
The result is precise enough to assert temperature differences
due to increased absorption in the vibrational frequency subrange
of greenhouse gasses.

●セミナー室: 京都大学 総合研究12号館 2階203号
              （応用解析学講座セミナー室）

●総合研究12号館はキャンパスマップでは「京都大学本部構内 54番建物」です。
-------------------------------------------------------------
セミナー連絡先: 京都大学大学院 情報学研究科 先端数理科学専攻
                 磯 祐介    e-mail; iso at i.kyoto-u.ac.jp