We study the enhanced atomization of viscous liquids by employing a novel two-fluid atomizer. The nozzle establishes a countercurrent flow configuration in which the gas and liquid are directed in opposite directions, establishing a two-phase mixing layer. Detailed measurements of droplet size distributions were carried out using laser shadowgraphy, along with high speed flow visualization. The measurements suggest that the liquid emerges as a spray with little further secondary atomization. The performance of this nozzle is compared to the ‘flow-blurring’ nozzle studied by other investigators for four test liquids of viscosity ranging from 1 to 133.5 mPa.s. The counterflow nozzle produces a spray whose characteristics are relatively insensitive to fluid viscosity over the range studied, for gas-liquid mass flow ratios between 0.25 and 1. To gain insight into the mixing process inside the nozzle, simulations are carried out using an Eulerian-Eulerian Volume of Fluid (VoF) approach for representative experimental conditions. The simulation reveals the detailed process of self-sustained flow oscillations and the physical mechanism that generate liquid filaments and final droplets.
|Original language||English (US)|
|Title of host publication||Combustion, Fuels, and Emissions|
|Publisher||American Society of Mechanical Engineers (ASME)|
|State||Published - 2020|
|Event||ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition, GT 2020 - Virtual, Online|
Duration: Sep 21 2020 → Sep 25 2020
|Name||Proceedings of the ASME Turbo Expo|
|Conference||ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition, GT 2020|
|Period||9/21/20 → 9/25/20|
Bibliographical notePublisher Copyright:
© 2020 American Society of Mechanical Engineers (ASME). All rights reserved.
- Mixing layer
- Viscous liquids