Thermal Lattice Boltzmann Simulation of Evaporating Thin Liquid Film for Vapor Generation

• Published in: Applied sciences Vol. 8; no. 5; p. 798
• Main Authors: Yang, Weilin, Huang, Haibo, Yan, Wenxu
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.05.2018
• Subjects: Boundary conditions; Boundary layers; Computational fluid dynamics; double distribution; Efficiency; Evaporation; Experimental methods; Finite volume method; Flow rates; Fluids; Heat flux; Heat transfer; Iron; Mass flow rate; Measuring instruments; Nanotechnology devices; Partial differential equations; Phase transitions; Quantitative analysis; Research methodology; Simulation; Studies; Temperature; thermal lattice Boltzmann method; Thermal simulation; Thickness; thin film evaporation; Thin films; vapor generation; Vapors; Velocity; United States > US; China
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app8050798

[...]some assumptions should be made if a simplified problem is considered instead, which weakens the physical meaning. Since TFE is usually considered in micro-scale and even nano-scale devices, measuring the physical quantities, such as the thickness of liquid film and the local temperature, via experimental methods is also challenging. By changing the pore width and adopting the corresponding heat flux at the solid walls according to Equation (41), scenarios with various pore width are realized. Since the vapor outlet is connected to the ambient, a constant density and temperature corresponding to the ambient are assumed for the boundary layer of the outlet. According to Equation (42), efficiency is mainly dominated by the mass flow rate m˙ , since the input power Qa and the enthalpy change hfg does not vary much. [...]we have the following relationship η∝fe Ae, where fe is the mass flux of vapor, and Ae is the surface area for evaporation.