Steady-state and transient solutions to drop evaporation in a finite domain: Alternative benchmarks to the d2 law. (December 2018)

• Record Type: Journal Article
• Authors: Pathak, Ashish; Raessi, Mehdi
• Is Part Of: International journal of heat and mass transfer. Volume 127(2018)Part A
• Page Start: 1147
• Page End: 1158
• Publication Date: 2018-12
• Subjects: Drop evaporation -- d2 law -- Transient -- Steady-state -- Analytical -- Benchmark -- Computational -- Finite domain; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2018.06.071
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: Novel closed-form analytical expressions for drop evaporation in finite domains. A body-fitted radially symmetric transient evaporation model. A new transient phenomenon observed toward the end of the lifetime of an evaporating drop. Abstract: The d 2 law, commonly used to assess the accuracy of computational solvers, corresponds to evaporation under steady-state conditions and in an infinite gaseous domain. In the present work, we propose new alternative benchmarks that relax those constraints. The benchmarks are developed for a spherical as well as a circular drop. First, steady-state analytical relations are derived that are applicable to a finite domain. A radially-symmetric transient model is then proposed that can provide transient benchmark solutions in finite domains. Adaptive mesh-refinement and body-fitted mesh are used for numerical solution and to ensure highly accurate transient results. The proposed steady-state and transient benchmarks are examined in several evaporation problems, and the evolution of drop diameter, temperature and vapor mass fraction fields are analyzed. In one such problem, we report a secondary transient phenomenon that appears towards the end of drop lifetime. The benchmarks proposed in this work are straightforward to be implemented for systematic validation of computational solvers.