Comparative Investigation on Droplet Evaporation Models for Modeling Spray in Cross-Flow

Abstract

The coupling model of flow and heat and mass transfer for gas-spray droplet two-phase flow has been developed to simulate the evaporating spray in cross-flow. The correlations used for describing the droplet evaporation and motion in convective flow have been compared. The comparisons of calculated results show that the different correlations for determining Nusselt number and Sherwood number impose a significant influence on the lifetime of droplet. The modification of Nusselt number and Sherwood number with regard to the heat and mass boundary around the droplet is of great importance, while different mixing laws for mixture properties and different drag coefficient equations only demonstrate a slight effect on the evaporation characteristics of droplet. The characteristics of spray droplets and cross-flow in terms of both evaporation and motion are obtained. The secondary flow phenomenon is observed in the simulation results and contributes to achieving a more even distribution of temperature and an improved mixing effect of the vapor and cross-flow.

Modelling of heating and evaporation of n-Heptane droplets: Towards a generic model for fuel droplet/particle conversion

“…There are a few groups of liquid phase sub-models and also quite some different correlations for calculation of, e.g., the Sherwood and Nusselt numbers, droplet surface velocity, and drag coefficient and so on [16,20,21]. Here the focus is placed on the validation results, rather than a comparative analysis of the variations in sub-models or correlations.…”

Spray in cross–flow: comparison of experimental and numerical approach

“…Cd=(24/Re) (5) 1<Re <10 5 Cd=(24/Re)(1+0.173Re 0.657 )+0.413/(1+16300Re -1.09 ) (6) 3. Ansys Setup 3…”

“…Models for heat and mass transfer were also added to the sprays in crossflow. Sun et al [5] compared different models for heat and mass transfer for a spray injected to the cross-flow. Different corelations yield very different results on droplet evaporation.…”

Temperature Patterns of Air Crossflow with Hollow-Cone Spray Evaporation

“…First, a simply droplet evaporation model that will be used in the analyses is given here. According to the studies on droplet evaporation [32,33], the evaporation rate of a spherical droplet in high-temperature gas flow can be expressed in terms of heat transfer by…”