ABSTRACT
The proposed two-dimensional numerical solution scheme for internal and external flows solves the full Navier-Stokes equations in each phase, and locates the phase change interface while satisfying all the conditions at the interface, inlet, outlet, and the walls. It is used to solve classical smooth-interface external film condensation problems and gives results in excellent agreement with classical solutions. The research results show that conditions at the exit of an internal condensing duct flow, unlike single phase or other noncondensing gas-liquid incompressible flows often significantly influence the flow upstream and are responsible for determining the nature of wavy-interface quasi-steady flows. The smooth interface can be replaced by a stair-step type surface. The grid generation technique allows us to choose a denser grid near the flat part of the interface.
