The dynamics of the head of a gravity current advancing over a horizontal surface

摘要: The motion behind the head of a gravity current advancing over no-slip horizontal surface is complex three-dimensional flow. There intense mixing between and its surroundings foremost part raised above surface. Experimental results are obtained from (i) an apparatus in which brought to rest by using opposing flow moving floor (ii) modified lock exchange dimensionless velocity advance, rate two fluids depth mixed layer left following determined for extended range depth. result gravitational shear instabilities at head. A semi-empirical analysis presented describe results. influence Reynolds number discussed comparison with documented atmospheric presented.