Q: That section you had us read on multiphase flow (2.4) was really abstract. Would you give some examples of the practical importance of multiphase flows?
A: I suspect that multiphase flows are the rule. In biology we have blood flow, digestion, lymph flow, cellular perfusion, and aerosol transport—all of which involve the relative motions of more than one phase. In industrial or manufacturing processes we have coatings, foods, cosmetics, and pharmaceuticals, all of which require consideration of multiphase flow. In environmental science we have sediment transport, pollutant transport, soil liquefaction, and plate tectonics, all of which involve multiphase considerations.