Oberseminar Numerische Mathematik / Scientific Computing
Ryo Onishi
Earth Simulater Center (ESC), Japan
Explicit droplet collisions in turbulent clouds in the MSSG model
Abstract:
Firstly, an atmosphere-ocean coupled model named MSSG (Multi-Scale Simulator for the Geoenvironment) is briefly introduced. The MSSG is designed for seamless simulations: It is based on an ordinary latitude-longitude coordinate for micro- and meso-scales, while yin-yang coordinate (overlapped two latitude-longitude coordinates) for global-scales. It also has a dynamic mesh refinement system for efficient calculations of multiscale interactions.
Second part is on my own research concerning multiphase phenomena in in-cloud turbulence. Particularly, the turbulent collision among cloud droplets, to which some rapid cloud developments are often attributed, is discussed in this talk. A spectral-bin cloud microphysics scheme -where sizes of water droplets are explicitly calculated- has been implemented in the MSSG. The use of a turbulent collision kernel model enables the spectral-bin scheme to investigate the impact of turbulent droplet collisions on cloud development. High-resolution cloud simulations (up to 20m spatial resolution for 512x512x200 grids) using the MSSG spectral-bin scheme reveal the significance of turbulent droplet collisions.
| Datum: | 07.06.10 | Zeit: | 17:00 Uhr | Ort: | FU Berlin, Institut für Mathematik, Arnimallee 6, 14195 Berlin. | Raum: | 031 im Erdgeschoss |