Shafaee Roshani M, Ouni A. Experimental Study of Spray Characteristics of Pressure-Swirl Atomizers and Determination of Droplet Size Distribution Function. Modares Mechanical Engineering 2024; 25 (1) :11-21
URL:
http://mme.modares.ac.ir/article-15-78124-en.html
1- University of Tehran , mshafaee@ut.ac.ir
2- University of Tehran
Abstract: (233 Views)
cost-effectiveness, and reliability. Despite numerous experimental studies on pressure-swirl atomizer spray, a comprehensive mathematical model for predicting spray characteristics has not yet been presented. Additionally, there is no consensus on the distribution function accurately describing droplet size dispersion. In the present study, the main characteristics of pressure-swirl atomizer spray, including discharge coefficient, spray cone angle and droplet size distribution, were experimentally investigated using the shadowgraph technique. The study spanned a wide range of Reynolds numbers, from 1250 to 8500, encompassing laminar, transition, and atomization regimes. The findings showed that the discharge coefficient initially declined during the transition stage, followed by a gradual increase up to the atomization regime. In the atomization regime, the discharge coefficient remained almost constant. A similar trend was observed for the spray cone angle throughout the transient and atomization phases. The gamma distribution function provided a favourable fit with the experimental drop size distribution in the near-ligament location, where primary breakup mechanisms dominate. The log-normal distribution function showed superior fitting with the experimental droplet size distribution for regions distant from the liquid sheet disintegration point, where secondary breakup mechanisms exert a more pronounced influence on droplet dispersion. Overall, these findings provide valuable insights into spray characteristics and associated uncertainties.
Article Type:
Original Research |
Subject:
Two & Multi Phase Flow Received: 2024/11/23 | Accepted: 2025/01/21 | Published: 2024/12/30