ESC seminar No. 54
Progress and problems in tera/peta simulations for Geophysical Fluid Dynamic processes
- Date
- May. 17 (Mon.), 2010, 14:00-15:30
- Place
- Conference Room, 1F Earth Simulator Research Building, YES, JAMSTEC
- Speaker
- Prof. Julian Hunt (University College London, UK)
- Language
- English
Abstract
Recent progress is reviewed for simulation of multi scale processes over 100,000,3-dimensional elements. These simulations at the ESC of turbulence, led by Prof Y Kaneda, have not only provided detail about the flow structure at high Reynolds number, but have fundamentally changed some basic concepts of turbulence that were beginning to emerge from theoretical work and other simulations/experiments. The simulations showed that turbulence adjusts fast, that upscale transport is comparable to downscale transport and that the micro-length-scale but energetic motions lie within thin layers which are a sink of energy transported by intermediate scale eddies impinging on these layers. This new conceptual model indicates how to compute interactions between turbulence and other processes, which are so small in scale that they cannot be computed explicity(eg heat transfer and particle coalescence). On the scale of GFD flows such as the ocean boundary layer, waves, weather fronts and synoptic scales, massive computations can also provide insights and lead to sub models that can be used in global climate models and global process models. The question of up scale and down scale transport, and the role of wave motion (elliptic/hyperbolic)is also critical on these length and time scales. This fundamental understanding is needed to construct and make best use of statistical approaches, such as ensemble modelling.
Contact
Keiko TakahashiEarth Simulator Center
TEL: 045-778-5834
e-mail:
