A research group from Nagoya University and Tohoku University recreated the clear-air turbulence that occurred in the sky above Tokyo Bay in the past through ultra-high-resolution weather simulations using the supercomputer Fugaku.In addition, the validity of the calculation was shown using shaking data recorded by an airplane that encountered clear-air turbulence at that time.
Clear-air turbulence is a sudden change in airflow that occurs in clear, cloudless weather.When you are on an airplane flying at a high altitude, you may experience a sudden violent shake in the cabin due to this clear-air turbulence.Numerical simulations have been used to investigate clear-air turbulence, but most of them are limited to reproducing the phenomena that caused turbulence.Few studies have attempted to reproduce turbulence itself, including fine eddies, especially at the high altitudes at which airplanes fly.
The research group conducted ultra-high-resolution simulations using a numerical meteorological model with grid width narrowed to 3 m, and reproduced turbulence in clear-air turbulence cases that often occur 4-35 km above Tokyo Bay in winter.In addition, by comparing it with shaking data recorded by airplanes at the time, it was examined whether the reproduced turbulence was correct.As a result, calculations with higher grid resolution were closer to the actual shaking.This showed that the plane was shaking under the influence of fine vortices that were directly reproduced in high-resolution calculations.
The research group believes that high-resolution simulations will lead to clarification of the principles and mechanisms of turbulence generation, as well as more detailed investigations of the effects of turbulence on aircraft.It is also expected that it will be possible to make turbulence forecasts with improved accuracy for airline operators.
Paper information:[Geophysical Research Letters] Clear Air Turbulence Resolved by Numerical Weather PredictionModel Validated by Onboard and Virtual Flight Data
