ON INSTABILITIES IN HORIZONTAL 2-PHASE FLOW

Two regions of instabilities in horizontal two-phase flow were detecte d. The first was found in the transition from slug to annular flow, th e second between stratified and slug flow. The existence of oscillatio ns between the slug and annular flows can explain the differences in t he limitation of the slug flow in flow regime maps proposed by differe nt authors. Coexistence of these two regimes is similar to bistable be haviour of some differential equation solutions.