International Journal of Multiphase Flow, vol.177, 2024 (SCI-Expanded)
A comprehensive experimental investigation is conducted to analyze the effects of momentum ratio and impingement angle on impinging spray characteristics of triplet and pentad injectors by using Phase Doppler Anemometry (PDA) and a mechanical patternator. Results from the triplet and pentad injectors show that an increase in the momentum ratio causes a decrease in the mass flux, resulting in a more uniform spray distribution. It is observed that this leads to better atomization in terms of the normalized droplet count with triplet injectors. In addition, when compared to the 45° and 60° impingement angles at the same momentum ratio, the 90° impingement angle gives a higher number of droplets spread over a larger region for triplet injectors. In contrast, the normalized droplet count decreases with an increase in the impingement angle and momentum ratio in the case of pentad injectors. It is observed that for the impingement angle of 60°, triplet injectors are superior to pentad injectors in terms of atomization. The triplet injector with an impingement angle of 90° offers improved atomization at higher momentum ratios compared to all configurations studied. For both injector types, the 45° impingement angle produces a poor spray distribution. The spray angle is observed to be a strong function of both the impingement angle and momentum ratio for triplet injectors, while it is relatively less affected by these two parameters for pentad injectors.