AN INVISCID INVESTIGATION OF THE INITIATION OF ROLL WAVES IN HORIZONTAL GAS-LIQUID FLOWS

A model with constant vorticity in the liquid phase has been applied t o the study of interfacial waves between two inviscid fluids in relati ve motion, in order to take into account the shear induced into the li quid by the concurrent gas flow. For a range of values of gas velocity and vorticity in the liquid phase a new wave pattern is calculated, c onsisting of a recirculating eddy below the wave crest. It is suggeste d that, under certain conditions, the onset of this new type of waves (rather than the classical Kelvin-Helmholtz instability mechanism) pro vides the inviscid analog to the experimentally observed transition to roll waves.