Abstract:
Annular flow is the configuration of gas/liquid flow in which some of the liquid travels as a film on the channel walls and the rest is carried as drops by the gas in the center of the channel. The fraction of liquid traveling as drops varies from zero to close to one. In vertical flow the film is fairly uniform about the pipe circumference but for inclined and horizontal pipes, gravity causes a significant asymmetry of the film, much higher flow rates and film thicknesses at the bottom than at the top. For downward flows there are wide ranges of conditions where the liquid flows entirely as a film.
Annular flow is important because it occurs in a wide range of industrial equipment particularly used in the chemical and nuclear industries. However, the experiments are uncomfortably costly in terms of both money and time and hence, alternatives to these are welcomed.
In this Master Thesis of 06 credit hours, the task undertaken was to simulate and create two-phase vertical annular flows of water and air with the help of the CFD code FLUENT.
Eulerin model of Fluent was used for the two phases and RNG K- model for the turbulence. Two separate phases (liquid and water) in the form of Annular flow were observed in the results.