2D and 3D simulations of a nonhydrostatic atmospheric model on a block-structured Cartesian mesh
Seminar Room 1, Newton Institute
Under the rapid development of computing power, this study aims at developing a next-generation atmospheric model for ultra-high resolution simulations at horizontal grid intervals of less than 100 meters. Recently, Cartesian grids are drawing attention as an attractive choice for high-resolution atmospheric models that need to handle steep slopes in mountainous areas. They have the advantage of avoiding errors because of the slantwise orientation of grid lines in models using conventional terrain-following grids. In our model, a cut cell method is used for representing topography on a Cartesian grid. Also, a block-structured mesh approach is introduced to achieve computationally efficient Cartesian grid simulations with both high vertical resolution near the ground and reasonable conservation characteristics.
The result of a 2D numerical simulation shows the model successfully reproduces a flow over a semi-circular mountain on a locally refined mesh around the mountain. The result agrees well with that using a uniformly fine mesh. Some recent 3D results of our model will also be discussed.