Heat and mass transfer in the liquid film on a vertical wall in roll-wave regime

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

“…3 shows the experimental data on the change in the total heat flux (q Σ ) over time (t). The heat balance equation for the free surface of a liquid has the form (1). q Σ =q w =q h +q e +q c + q r , (1) were q w =λ w (dT/dy) y=0 is the heat flux density of the wall, q h =c p d(m∆T 1 )/dt·(1/F) is the heat flux due the liquid heating, q e = rj/F is the heat flux due to evaporation, q c =α g (T s -T 0 ) is the heat flux due to gas convection, q r =εσ(T s 4 -T 0 4 ) is the heat flux due to radiation, λ w is the thermal conductivity of the titanium alloy, y is the coordinate transverse to the metal wall (y=0 corresponds to the surface of the wall), c p is the heat capacity of liquid, r is the latent heat of desorption for the aqueous salt solution, j is the evaporation rate (j=∆m/(∆tF)), m is the change in the layer mass, t is the time, r is the latent heat of vaporization, F is the area of interface of the layers, t is the time, T 1 is the average temperature throughout the layers volume, ε is the coefficient of thermal radiation for the liquid, σ is the Stefan-Boltzmann constant, and T 0 is the ambient temperature.…”

“…Desorption and absorption of aqueous salt solutions of LiBr, CaCl 2 are used in desorbers and absorbers of heat pumps. Phase transformations in heat pumps depend on the heat flux [1,2]. The nonisothermal desorption of aqueous salt solutions at a temperature below boiling was studied in [3][4][5].…”

Numerical Simulation of Heat and Mass Transfer in a Liquid Film Moving Over a Heated Horizontal Surface Under the Action of a Gas Flow

“…It is assumed that the shear stress applied to the interface will allow intensification of the process of heat and mass transfer in comparison with the fixed-vapor regime. The investigation of thin liquid film flowing down a vertical wall in the roll-wave regime in presence of heat and mass transfer through the free surface was presented in [3,4]. The absorption and desorption processes under the conditions, corresponding to the operating modes of thermal transformers are described in [5].…”

Studying Periodic Rolling Waves on the Surface of a Falling Liquid Film

“…A possibility of traveling wave existence on the surface of a vertically falling liquid film without consideration of surface tension is shown in [3], and the equation, describing propagation of these waves, so-called kinematic equation, is also derived there (exact discontinuous solutions to this equation correspond qualitatively to the experimental results). In [4], the flow of a thin liquid film on a vertical wall was studied theoretically with consideration of condensation at the interface in the regime of the rolling waves. The families of discontinuous solutions were derived, where the traveling waves conjugate with each other or with a residual thickness through strong and weak discontinuities.…”

“…The maps of flow regimes of the liquid film on a vertical heat transfer surface were plotted. Based on the model developed in [3][4][5], the traveling waves on the surface of a falling liquid film were studied in [6], taking into account heat and mass transfer and surface tension. …”