Mathematical modeling and transient thermal-hydraulic analysis of boiling water reactors

Moving‐boundary analysis of net vapor generation point in a steam generator

“…With the assumptions of insignificant viscous dissipation, negligible compressibility of liquid phase and constant pressure [13][14][15], the equations have been combined to set up the governing equation given by Equation (3).…”

“…Instead of assuming equilibrium boiling (saturated boiling) conditions at the boundary, as proposed by [9,[13][14][15], the correlations of Saha and Zuber [16], which cater to the effect of thermal non-equilibrium between phase and liquid phase, have been used to calculate more accurate liquid enthalpy at the boundary. Saha and Zuber experimentally verified the fact that subcooled boiling condition prevails at NVG point and proposed phenomenological correlations given by Equation (11) for a typical boiling channel.…”

“…The analytical solutions given by Equation (14) are presented in Figure 15 that the boiling channel experiences the effect of the change in heating rate without any time delay. The boiling height decreases fast with the increase in heating rate.…”

“…Although a significant amount of work on moving boiling boundary problems have already been carried out, the literature survey [9,[13][14][15] shows that more realistic boundary conditions at NVG point (boiling boundary) are required for sharp tracking of the position of the interface between single-phase region and two-phase region. It is also needed to compare the performance of the numerical schemes to determine the suitability of the scheme to solve the present moving-boundary problem and other problems of similar nature.…”