Introduction Good mixing is a major challenge in many areas of chemistry and chemical engineering, ranging from continuously stirred tank reactors (CSTRs)  to industrial level processes , where imperfect mixing can adversely aect product quality and yield. Many of us are familiar with mixing problems in making bread, stirring paint, mixing gasoline and air in internal combustion engines, and mixing driven by density dierences (salt water-fresh water convection) but even mixing of ordinary liquids can pose challenges. (e density of pure water is 1000 kg/ m3. Ocean water is more dense because of the salt in it. Density of ocean water at the sea surface is about 1027 kg/m3. ere are two main factors that make ocean water more or less dense than about 1027 kg/m3. From http://www.csgnetwork. com/h2odenscalc.html we derived Table 1 (accessed 1/2009)).