Optimizing the Auxiliary Air Channels of a Vortex Atomizer by 3D Printing Using the Taguchi Method

Abstract

In this study, the optimum spraying performance of a pressurized vortex atomizer using water as the working fluid was investigated experimentally by modifying the geometry of auxiliary air holes via the Taguchi method. The experimental results were also examined by CFD simulations. The four control factors of the auxiliary air holes are their numbers, areas, inclination angles, and lengths. With five levels for each control factor, an L25 orthogonal table was selected. Each case of the L25 orthogonal table was test repeatedly three times to obtain key average results. The auxiliary air holes were designed by a KISSlicer CAD tool and fabricated by 3D printing. The 3D printing was carried out by fused deposition of PLA with a resolution of about 30 μm. In the experiments, the spraying jet patterns were recorded, and the water droplet weights were measured. By using the signal to noise ratios and the smaller-the-better quality characteristic, the effect of the control factors of the auxiliary air holes in descending order is the numbers, areas, inclination angles, and hole lengths, respectively. The optimum air hole configuration is the one with six holes, an inclination angle of 20°, an area of 18 mm2, and a length of 8 mm. The optimum condition was confirmed by a signal to noise ratio of 20.5 dB with 95% confidence interval. The resulting smaller jet opening angle is about 42°, close to the simulated angle of 45°. That is, by the novelty of combining 3D printing with the Taguchi method, this study obtains the optimum design with fast prototyping and relatively few experiments.