Analysis and numerical modeling of subcooled boiling in energy systems in vertical porous channel

Abstract

Boiling phenomena are interested in many fields of engineering such as piping and cooling electronic systems. Usually, the phase change through the heat transfer process is avoided as it makes the fluid flow unstable and complex. In the current study, the effect of using porous media in the channel to control the thermo-hydraulic characteristics of the system is studied. To do this aim a steady-state one-dimensional system of equations is solved by numerical method. The gas and liquid Navier–Stokes equations coupled with energy equations are solved simultaneously. The developed method validated with a well-known benchmark problem and the comparison shows a good agreement. The results show that Sauter bubble diameter, forces on the cross-sectional area of fluid, Froude number, fluid wall forces, velocity of mixture, Reynolds number of vapor, fluid velocity, square root of Froude number divided by Weber number, base volume fraction, vapor volume portion, maximum vapor volume portion, critical vapor volume fraction decrease by an increase in Darcy forces, while mean root square of the applied force over the cross section of fluid and heat transported by thermal radiation increased by an increase in Darcy friction up to 1000. The porous media parameters have negligible effects on Eotvos number, speed of sound, liquid Reynolds number, bubble departure frequency, convection heat transfer coefficient, and critical pipe diameter.