Effect of a constant heat source on evaportive instability in a solid-liquid-vapor system

Abstract

When a liquid underlies its own vapor, convection may arise due to evaporation without gravity or surface tension gradient e ects. This process is named as pure evaporative convection. In this study, standard linear stability of a solid-liquid-vapor system considering an evaporative liquid into its own vapor is investigated. A constant heat source is considered in the solid part of the system and the e ect of that heat source on the linear stability is studied. Inputs to the system are the constant heat, the depths of the solid, the liquid and the vapor and the physical parameters, which are assumed to be constant while the output is the temperature di erence at which convection starts. The aim is to parametrically analyze this system and compare it with a liquid-vapor system where the bottom plate is kept at constant hot and upper plate at constant low temperature. In the study, the e ect of the heat source number, which appears in the energy balance equation for the solid part, the solid depth, the liquid and the vapor ows on the critical evaporation number and dispersion curve are examined. It is concluded that the vapor ow stabilizes the system while the heat source number, the liquid ow and the solid depth destabilize the system.