Aktif ızgara ile oluşturulan anizotropik türbülanslı akışta damla parçalanmasının incelenmesi

Droplet breakup mechanisms play a critical role in various engineering systems, with their behavior strongly dependent on continuous fluid parameters, particularly velocity. While traditional studies define breakup modes across Weber number regimes under uniform flow conditions, the influence of turbulence on droplet breakup remains poorly understood. This study investigates the effect of turbulence on droplet instability to enhance atomization understanding. An experimental setup was designed incorporating a radial fan and an active grid system with ten independent shafts and square winglets, coupled with a specific-ratio nozzle to generate controlled anisotropic turbulence. Through high-speed imaging and hotwire-anemometry measurements, 7,200 droplets were analyzed alongside nearly 1 billion hotwire measurements, which is equivalent to a total of 48 hours of hot-wire measurement campaign. Results demonstrated that active grid motion significantly altered droplet breakup mechanisms, particularly in lower Weber number ranges where atomization changes were most pronounced. Image processing quantification of atomization intensity confirmed these effects. These results also display the significant effects of the local turbulent structures and their statistical properties, such as turbulent kinetic energy and dissipation rate, on the instability and breakup regimes of the droplets. These results may be used to update existing models for more accurate prediction of turbulent breakup mechanisms and, at the same time, design of effective systems with increased atomization efficiency.