Spray Formation in the Multi-Hole Nozzle of Twin-Fluid Atomizers

Abstract

The atomization of internal-mixing twin-fluid atomizers is highly dependent on the internal geometry of the mixing chamber. Many studies have been conducted on the air entrance geometry influencing the air-fuel mixing. This paper aims to determine the effects of a multi-circular jet (MCJ) plate on the spray formation of twin-fluid atomizers. Plates 1, 2 and 3 with different open area ratios were used in the experiments. A swirler was used for comparison. The spray images were captured at different equivalence ratios using a direct photography method. ImageJ software was used to analyse the breakup length of spray formation. Results corroborate that, as the open area ratio of an MCJ plate increases, the break-up length decreases. The opening area for primary air entrance into the mixing chamber contributes to the airfuel mixing, thereby affecting the spray performance of twin-fluid atomizers.