A Unified CFD Based Approach to a Variety of Condensation Processes in a Viscous Turbulent Wet Steam Flow

Abstract

A family of quasi linear mathematical models is presented and calculations made for viscous turbulent wet steam flow with a variety of condensation phenomena. These models can be applied to the analysis of equilibrium condensation, homogeneous (spontaneous) condensation, heterogeneous condensation on extraneous particles, and condensation of charged dispersed phase moving in an electrostatic field. The unified model is represented by coupled systems of gas dynamic equations for viscous turbulent two-phase flow, kinetic and electro-kinetic equations tracing out combined processes of size and charge growth, and electromagnetic field equations described an electric field with an account of self-induced in-part by a moving electrical cluster. The numerical procedure is time marching, monotone, implicit, of second order accuracy by space and time coordinates, and exhibits high resolution shock capturing ability. Viscous flow field calculations made with this procedure reveal significant influence on condensation by the shear boundary layers and wakes. Distributions of cooling rate, droplet radius and parameters of the bulk flow are predicted. Verification of the codes against known experimental data is presented.

Numerical investigation of wet inflow in steam turbine cascades using NURBS-based mesh generation method

“…3, in order to achieve a suitable value of angle of the grid φ, three different values were considered. The first considered value of is selected as 0° which is investigated in many studies (see, e.g., Francesco et al [27], Liberson and Hesler [62], and Rueda et al [63]). The second value of is chosen as 64.4° so that the outlet periodic boundary is tangent to the pressure surface which has been suggested by some studies in the literature (see, e.g., Bkhtar et al [25,52] and Vatanmakan et al [7]).…”