Modeling of dro‎pwise Condensation in an Inclined Tube

11/19/2020 12:00:00 AM

The purpose of this thesis is the hydrodynamic and thermal analysis of saturated vapor stream Condensation when passing through an inclined tube. By entering the saturated steam stream enters the pipe, due to the temperature difference, some of it is condensate into liquid droplets on the upper part of the pipe and due to the weight of the droplets it flows to the bottom of the pipe and flows to the bottom of the pipe as saturation current. In addition to the effect of tube inclination, the effect of interfacial shear stress, axial pressure gradient, inlet saturation vapor mass flow rate and its associated temperature, propulsion temperature difference and fluid volume accumulation in the pipe floor is included. The physical model considered consists of three distinct areas: condensate droplets flow over pipe wall, condensate layer accumulated at the bottom of the tube and steam flow through central pipe area. Since the equations presented in the present problem are often nonlinear and complex, so a finite difference method is used to solve the equations. Separate flow models have also been used to analyze the different parts of the flow and the interaction effect between the phases has been taken into account. Using the distilled inlet steam rate at the inlet of the tube and obtaining the thermophysical properties available for subsequent steps, one can obtain the cumulative amount of each step by this process and then obtain the values of the heat transfer coefficient and the amount of heat flux at each section of the pipe. The results of this study show that the values of heat transfer coefficient and heat flux have higher values than the filmwise condensation, which makes this method more obvious. By examining the inclination effect, the numerical results showed that the amount of heat flux increases with increasing pipe inclination, with the highest percentage increase being 17.2% relative to the horizontal state of the Tube.