Large-Eddy Simulation #40: 6.4 x 6.4 km Homogeneous CBL

The purpose of this run was to simulate a relatively simple (homogeneous) convective boundary layer and compare the results with those in a paper by Nieuwstadt et al. (1993). The model is initialized with a neutral sounding that has a little bit of random noise added to it. It is driven by a constant homogeneous 0.06 K m/s sensible heat flux from the surface and there is no moisture in the model. We intend to compute profiles of turbulence statistics from this run for comparison with other LESs and observations of this relatively standard case. The grid used here is set to match the models described in the Nieuwstadt et al. paper.

Domain size 40x40x50 grid-points. Click here to see the NMSTASK file.
This domain is 6.4 km (east-west) by 6.4 km (north-south) wide.

The horizontal slice of w shown above (200 m above the surface) contains coherent polygonal spokes and cells that have been observed in other LESs (for example, see Schmidt and Schumann, 1989, JFM, 511-562) and our Volume Imaging Lidar data (10 Jan 98 14:16-14:57 Z and 13 Jan 98 16:25-16:30 Z).

UW Lidar // Feb 18, 1999 //

Return to the Index