Sharif Digital Repository

Density currents are continuous currents which move down-slope due to the fact that their density is greater than that of ambient water. The density difference is caused by temperature differences, chemical elements, dissolved materials, or suspended sediment. Many researchers have studied the density current structures, their complexities and uncertainties. However, there is not a detailed 3-D turbulent density current data set perfectly. In this work, the structure of 3-dimensional salt solution density currents is investigated. A laboratory channel was used to study the flow resulting from the release of salt solution into freshwater over an inclined bed. The experiments were conducted... 

Lake Urmia, which was once the second-largest saline lake in the world, has been shrinking dramatically. Moreover, Lake Urmia has become supersaturated with total salinity averaging more than 350 g/l. Salt precipitation and dissolved materials brought by inflowing rivers have formed a layer of sediment with low hydraulic conductivity on the lakebed. Considering the flat bathymetry of Lake Urmia, we conducted a series of numerical simulation scenarios to study the groundwater flow pattern in the vicinity of the hypersaline Lake Urmia using COMSOL Multiphysics®. In the first step, we performed the simulations in steady-state conditions. Secondly, we simulated the lake level fall in 10 years at...