Large-Eddy Simulation #256: IBL with tracer inflow problem

LES RUN #256: Internal boundary layer on 13 Jan 98 initialized with the 30-minute solution to LES#252 by east-west replication. Flow recycler turned on. Span-wise slice to extract perturbations at 3 km downstream of the west wall. Click here to see the NMSTASK file of LES #256.

The following 2-panel animation shows (1) simulated aerosol backscatter on a horizontal slice 7.5 m above the surface and (2) a line-plot of mean backscatter versus distance. The clearing that moves from west to east during the simulation is caused by lack of passive tracer on the inflow wall. This problem will be fixed in future simulations--but represents an unique opportunity to observe the advection time of the passive tracer across the domain.



The following 3-panel animation shows the same as above PLUS a third panel that shows the distance of the clearing as a function of time. This plot may be useful in translating time in the Lagrangian run to distance in the fixed-domain runs.



The following image shows all the mean backscatter profiles as on the 7.5 m horizontal plane as a function of time as a color image.







The following animation shows vertical velocity on a horizontal slice 7.5 m above the surface. The first 150 frames (30-minutes) are from LES#252 and show spin-up of the smaller domain. The subsequent frames are all from LES#256 which is the 6.6 million grid point domain. LES#256 is started by taking the perturbations at 1800s in #252 and replicating them 4 times across the larger domain.



The following animation shows vertical velocity on a horizontal slice 98 m above the surface.



The following animation shows vertical velocity on an east-west vertical slice.



The following animation shows simulated aerosol backscatter on a horizontal slice 7.5 m above the surface. The first 150 frames (30-minutes) are from LES#252 and show spin-up of the smaller domain. The subsequent frames are all from LES#256. The clearing that moves from west to east during the animation is caused by lack of passive tracer on the inflow wall. This problem will be fixed in future simulations.



UW Lidar // Jan 8, 2001 // root@lidar.ssec.wisc.edu

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