Modelling transverse dunes
نویسندگان
چکیده
Transverse dunes appear in regions of mainly unidirectional wind and high sand availability. A dune model is extended to two dimensional calculation of the shear stress. It is applied to simulate dynamics and morphology of transverse dunes which seem to reach lateral invariance and do not stop growing. Hence, simulations of two dimensional dune fields have been performed. Characteristic laws were found for the time evolution of transverse dunes. Bagnold’s law of the dune velocity is modified and reproduced. The interaction between transverse dunes led to interesting results which conclude that small dunes can pass through bigger ones.
منابع مشابه
Numerical modelling of airflow over an idealised transverse dune
The general flow structure over transverse aeolian dunes is now well documented through both field studies and wind tunnel experiments. Research on windward (stoss) slopes of dunes is extensive and has recently been complemented by research on the lee-side flow structure. However, a number of technical deficiencies in wind tunnel instrumentation and a lack of detailed resolution in and appropri...
متن کاملModelling formation and evolution of transverse dune fields
We model formation and evolution of transverse dune fields. In the model, only the cross section of the dune is simulated. The only physical variable of relevance is the dune height, from which the dune width and velocity are determined, as well as phenomenological rules for interaction between two dunes of different heights. We find that dune fields with no sand on the ground between dunes are...
متن کاملAeolian Processes across Transverse Dunes. Ii: Modelling the Sediment Transport and Profile Development
This paper discusses a model which simulates dune development resulting from aeolian saltation transport. The model was developed for application to coastal foredunes, but is also applicable to sandy deserts with transverse dunes. Sediment transport is calculated using published deterministic and empirical relationships, describing the influence of meteorological conditions, topography, sedimen...
متن کاملCalculation of the separation streamlines of barchans and transverse dunes
We use FLUENT to calculate the wind profile over barchans and transverse dunes. The form of the streamlines of flow separation at the lee side of the dunes is determined for a symmetric barchan dune in three dimensions, and for the height profile of a measured transverse dune field in the Lençóis Maranhenses.
متن کاملCalculation of the separation streamlines of barchans and transverse dunes using FLUENT
We use FLUENT to calculate the wind profile over barchans and transverse dunes. The form of the streamlines of flow separation at the lee side of the dunes is determined for a symmetric barchan dune in three dimensions, and for the height profile of a measured transverse dune field in the Lençóis Maranhenses.
متن کامل