An experimental study of mixing and instability development in variable-density systems

摘要

This study presents results of flow-tank experiments on variable-density flow in a layered system. Less dense water displaced more dense water in a system layered with a lower over a higher hydraulic condictivity unit. This configuration crated a potentially unstable interface between the displaced water and the displacing water. The displacing water wedge(i.e., less dense water)in the higher hydraulic conductivity layer traveled downgradient faster than the displacing water wedge moving in the layer above. Downward movement of more dense water from the upper layer into the freshwater wedge in the lower layer caused the latter to become more saline.