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Project properties |
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| Title | Turbulent dispersion under stable conditions |
| Group | Meteorology and Air Quality Group |
| Project type | thesis |
| Credits | 36 |
| Supervisor(s) | Arnold Moene |
| Examiner(s) | Prof. dr. AAM Holtslag |
| Contact info | |
| Begin date | 2018/01/01 |
| End date | 2019/02/01 |
| Description | The ultimate goal would be to study turbulent dispersion in transitional stable boundary layer, including the night-to-day transition (e.g. according to the third GABLS intercomparison case (see www.atmo.ttu.edu/basu/GABLS3/).
Turbulent dispersion of passive scalars or particles has been actively studied for daytime conditions where turbulence is vigorous, being enhanced both by shear and by buoyancy. However, for stable night-time conditions relatively little is known about dispersion. Turbulence is generally weak and vertical motion is suppressed by the stable stratification. One of the possible tools to study turbulent dispersion is the method of Large Eddy Simulation: explicit three-dimensional calculation of turbulent motion. However, in the case of a stable situation the most important turbulent eddies are no longer large, but are suppressed in size by buoyancy. As a result the dispersion of particles is for an important part determined by turbulent fluctuations that are not resolved by the model. The aim of this project is to investigate how well models for these unresolved motion work under stable conditions. This can be done by running the model at a higher resolution so that what is unresolved at low resolution can be studied at high resolution. The test case will be the very idealized stable boundary layer studied in the first GABLS intercomparison case (see Beare et al., 2006). A starting point for this study of dispersion will be the work of Weil et al (2006). The actual LES simulations will not necessarily be executed by the student (although this could be done), but he/she will concentrate on the statistical analysis of the particle dispersion. Beare, R.J.; MacVean, M.K.; Holtslag, A.A.M.; Cuxart, J.; Esau, I.; Golaz, J.C.; Jimenez, M.A.; Khairoutdinov, M.; Kosovic, B.; Lewellen, D.; Lund, T.S.; Lundquist, J.K.; McCabe, A.; Moene, A.F.; Noh, Y.; Raasch, S.; Sullivan, P. (2006). An Intercomparison of Large- Eddy Simulations of the Stable Boundary Layer. Boundary-Layer Meteorology 118 (2). - p. 247 - 272. Weil, J.C., E.G. Patton. and P. P. Sullivan (2006). Lagrangian Modeling Of Dispersion In The Stable Boundary Layer. 17th Conference on Boundary Layers and Turbulence. J3.4 (see http://ams.confex.com/ams/pdfpapers/111205.pdf) |
| Used skills | |
| Requirements | MAQ-22806 Atmosphere-Vegetation-Soil Interactions
MAQ-32306 Boundary-layer Processes |