NUMERICAL STUDY OF DROPLET-STREAM VAPORIZATION AT ZERO REYNOLDS NUMBER

Abstract

This paper presents a numerical simulation of the vaporization of an infinite stream of droplets in the limit of zero Reynolds number. Analytical transformations are developed so that the solutions can be sought in a regular domain, suitable for the finite difference method, and points can be clustered in high-gradient regions to guarantee precision for the numerical approximation without corresponding increase in the computational costs. Once obtained, the transformed equations are discretized, leading to an algebraic system of equations for the velocity potential and the temperature. This system is solved using subroutines available in scientific routines libraries, with interactive refinement of the solution. The transformations are then inverted, and the profiles within the physical domain are obtained for the quantities of interest. The results are compared with analytical solutions available to limiting cases, for validation purposes. Converged numerical solutions for a stream with different droplet spacings are presented, showing the effect of droplet interaction. The results indicate that the vaporization rate of a droplet in a stream can be obtained from the isolated droplet vaporization case times a function depending on the interdroplet distance.