Hydrodynamics of vapor-liquid flows in curvilined channels of separation devices of power plants

Abstract

The main factor that affects the efficiency of the separation process is the lack of contact with the surface of the shutter when moving in the flow of small droplets of wet steam. This process depends on the physical and chemical properties of the wet vapor, the dispersion of the droplets, the parameters of the movement of the two-phase medium, adhesion and edge angle, and the geometry of the channel. Purpose. Determination of the limit modes of operation of separation shutter devices depending on the dispersion and quantity of droplet liquid, flow parameters and geometric characteristics of curved channels. Methodology. The methodology is based on the analysis of the physical model of the movement of a two-phase medium under the action of mass and gravitational forces in a curved horizontal channel. Findings. A mathematical model is presented for determining the trajectory of a liquid droplet in a curvilinear corrugation channel of the louvered package of a separator-superheater. The main conditions of film destruction and dynamic droplet break-up are defined. A method for expanding the range of stable operation of separation devices is proposed. Based on the obtained correlations, the design of the blind package is optimized. Originality. Based on the analysis of the physical model of the movement of a two-phase medium in a curved horizontal channel, a mathematical model was developed and the limit of capture of the dispersed phase was determined. Practical value. The presented results allow optimization of separation devices of boiler drums, horizontal steam generators and steam superheater separators of the II circuit of VVER-1000, fuel preparation systems of GTU.