A study on the geometric characteristic influence on the liquid fuel flow in a three-way pressure-swirl atomizer

An important factor that affects the characteristics of combustion processes in the combustion chambers of aircraft engines is the fuel atomization. Semi-empirical methods are usually used to determine the characteristics of liquid fuel atomization by pressure-swirl atomizers. The input data for semi-empirical methods are the geometric parameters of the atomizer, as well as the spray cone angle and the nozzle discharge characteristic. These parameters can be obtained experimentally, which requires the availability of appropriate apparatus and a sample of a pressure-swirl atomizer, which is associated with significant material costs. An alternative way to determine these characteristics is to use numerical methods for modelling two-phase flows. Therefore, it is convenient to use a combination of empirical and numerical methods (hybrid method) to determine the spray parameters of a pressure-swirl atomizer. In this paper, we studied the effect of geometric and operating parameters on spray characteristics using the hybrid method, which includes the volume of fluid (VOF) numerical method and the semi-empirical equation. The calculation results are compared with empirical generalizations and experimental data of such parameters as the discharge coefficient, the air core ratio and the spray cone angle. The results of this work were compared with the values of such parameters as the air core ratio and the spray cone angle obtained using the proposed method and analytical techniques. (paper)