Nonisothermal desorption at nucleate boiling in a layer of aqueous salt solution

Abstract

This paper presents the results of experimental studies of nonisothermal desorption at nucleate boiling of layers of aqueous salt solutions of LiBr and CaCl2. The height of the layers is 2.8 mm. The wall temperature is 120 °C. The drop in the temperature of the interfacial surface (Ts) for salt solutions and distillate is associated with low thermal conductivity of the metal wall (titanium) and intense heat flow at nucleate boiling. A heat balance for a free liquid interface has been worked out. In 75 seconds after the beginning of evaporation, the heat flux for aqueous becomes quasi-permanent, and for aqueous salt solutions of CaCl2 and LiBr, the heat flux continuously decreases with time. This is due to the increase in the salt concentration in the solution and the drop in the equilibrium partial pressure of the vapor.